WO2013050367A2 - Procédé de production d'acide formique par réaction de dioxyde de carbone avec de l'hydrogène - Google Patents

Procédé de production d'acide formique par réaction de dioxyde de carbone avec de l'hydrogène Download PDF

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Publication number
WO2013050367A2
WO2013050367A2 PCT/EP2012/069458 EP2012069458W WO2013050367A2 WO 2013050367 A2 WO2013050367 A2 WO 2013050367A2 EP 2012069458 W EP2012069458 W EP 2012069458W WO 2013050367 A2 WO2013050367 A2 WO 2013050367A2
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Prior art keywords
phase
formic acid
mixture
tertiary amine
hydrogenation
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PCT/EP2012/069458
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German (de)
English (en)
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WO2013050367A3 (fr
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Thomas Schaub
Oliver Bey
Anton Meier
Donata Maria Fries
Randolf Hugo
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Basf Se
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Priority to BR112014008338A priority Critical patent/BR112014008338A2/pt
Priority to CA2851175A priority patent/CA2851175A1/fr
Priority to CN201280059095.3A priority patent/CN103974927A/zh
Priority to RU2014118032/04A priority patent/RU2014118032A/ru
Priority to IN3122DEN2014 priority patent/IN2014DN03122A/en
Priority to SG11201400997TA priority patent/SG11201400997TA/en
Priority to KR1020147011873A priority patent/KR20140074373A/ko
Priority to EP12766684.0A priority patent/EP2763950A2/fr
Publication of WO2013050367A2 publication Critical patent/WO2013050367A2/fr
Publication of WO2013050367A3 publication Critical patent/WO2013050367A3/fr

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/0201—Oxygen-containing compounds
    • B01J31/0202—Alcohols or phenols
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/0234—Nitrogen-, phosphorus-, arsenic- or antimony-containing compounds
    • B01J31/0235—Nitrogen containing compounds
    • B01J31/0237—Amines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/24—Phosphines, i.e. phosphorus bonded to only carbon atoms, or to both carbon and hydrogen atoms, including e.g. sp2-hybridised phosphorus compounds such as phosphabenzene, phosphole or anionic phospholide ligands
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
    • B01J31/24—Phosphines, i.e. phosphorus bonded to only carbon atoms, or to both carbon and hydrogen atoms, including e.g. sp2-hybridised phosphorus compounds such as phosphabenzene, phosphole or anionic phospholide ligands
    • B01J31/2404—Cyclic ligands, including e.g. non-condensed polycyclic ligands, the phosphine-P atom being a ring member or a substituent on the ring
    • B01J31/2409—Cyclic ligands, including e.g. non-condensed polycyclic ligands, the phosphine-P atom being a ring member or a substituent on the ring with more than one complexing phosphine-P atom
    • B01J31/2414—Cyclic ligands, including e.g. non-condensed polycyclic ligands, the phosphine-P atom being a ring member or a substituent on the ring with more than one complexing phosphine-P atom comprising aliphatic or saturated rings
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/02—Preparation of carboxylic acids or their salts, halides or anhydrides from salts of carboxylic acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/41—Preparation of salts of carboxylic acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C07C51/48—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
    • B01J2231/60—Reduction reactions, e.g. hydrogenation
    • B01J2231/62—Reductions in general of inorganic substrates, e.g. formal hydrogenation, e.g. of N2
    • B01J2231/625—Reductions in general of inorganic substrates, e.g. formal hydrogenation, e.g. of N2 of CO2
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
    • B01J2531/80—Complexes comprising metals of Group VIII as the central metal
    • B01J2531/82—Metals of the platinum group
    • B01J2531/821—Ruthenium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
    • B01J2531/90—Catalytic systems characterized by the solvent or solvent system used
    • B01J2531/98—Phase-transfer catalysis in a mixed solvent system containing at least 2 immiscible solvents or solvent phases

Definitions

  • the invention relates to a process for the preparation of formic acid by reacting carbon dioxide with hydrogen in a hydrogenation reactor in the presence of a catalyst containing an element from the 8th, 9th or 10th group of the periodic table, a tertiary amine and a polar solvent, with formation of formic acid-amine adducts, which are then thermally cleaved to formic acid and tertiary amine.
  • Adducts of formic acid and tertiary amines can be thermally cleaved into free formic acid and tertiary amine and therefore serve as intermediates in the preparation of formic acid.
  • Formic acid is an important and versatile product. It is used, for example, for acidification in the production of animal feed, as a preservative, as a disinfectant, as an adjuvant in the textile and leather industry, as a mixture with their salts for de-icing of airplanes and runways and as a synthesis component in the chemical industry.
  • the said adducts of formic acid and tertiary amines can be prepared in various ways, for example (i) by direct reaction of the tertiary amine with formic acid, (ii) by hydrolysis of methyl formate to formic acid in the presence of the tertiary amine, (iii) by catalytic Hydration of carbon monoxide in the presence of the teriary amine or (iv) by hydrogenation of carbon dioxide to formic acid in the presence of the tertiary amine.
  • the latter method of catalytic hydrogenation of carbon dioxide has the particular advantage that carbon dioxide is available in large quantities and is flexible in its source.
  • EP 0 181 078 describes a process for the preparation of formic acid by thermal cleavage of adducts of formic acid and a teriary amine.
  • the process for the preparation of formic acid comprises the following steps: i) reacting carbon dioxide and hydrogen in the presence of a volatile tertiary amine and a catalyst to obtain the adduct of formic acid and the volatile tertiary amine, ii) separation of the adduct of formic acid and volatile tertiary amine from the catalyst and the gaseous components in an evaporator, iii) separation of the unreacted volatile tertiary amine in a distillation column or in a phase separation device from the adduct
  • Formic acid and the volatile tertiary amine iv) base exchange of the volatile tertiary amine in the adduct of formic acid and the volatile tertiary amine by a less volatile and weaker nitrogen base, such as 1 -n-butylimidazole, v) thermal cleavage of the adduct of formic acid and the less volatile and weaker nitrogen base to yield formic acid and the less volatile and weaker nitrogenous base.
  • a less volatile and weaker nitrogen base such as 1 -n-butylimidazole
  • EP 0 181 078 the volatile tertiary amine in the formic acid adduct must be replaced by a less volatile and weaker nitrogen base, such as, for example, 1-n-butylimidazole, before the thermal cleavage.
  • a less volatile and weaker nitrogen base such as, for example, 1-n-butylimidazole
  • EP 0 181 078 A further significant disadvantage of the process according to EP 0 181 078 is the fact that the separation of the adduct of formic acid and volatile tertiary amine according to the above-described step ii) EP 0 181 078 takes place in an evaporator in the presence of the catalyst.
  • the cleavage leads to a significant reduction in the yield of adduct of formic acid and volatile tertiary amine and thus to a reduction in the yield of the target product formic acid.
  • EP 0 329 337 proposes the addition of an inhibitor which inhibits the catalyst in order to solve this problem.
  • Preferred inhibitors include carboxylic acids, carbon monoxide and oxidizing agents.
  • the preparation of formic acid therefore comprises the steps described above in EP 0 181 078 i) to v), wherein the addition of the inhibitor takes place after step i) and before or during step ii).
  • the catalyst can be recycled to the reaction.
  • a fundamental disadvantage of EP 0 329 337 is that a large part of the catalyst in the process is inhibited.
  • WO 2010/149507 describes a process for the preparation of formic acid by hydrogenation of carbon dioxide in the presence of a tertiary amine, a transition metal catalyst and a high-boiling polar solvent having an electrostatic factor> 200 * 10 -30 cm, such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1, 3-propanediol, 2-methyl-1, 3-propanediol, 1, 4-butanediol, dipropylene glycol, 1, 5-pentanediol, 1, 6-hexanediol and glycerol.
  • reaction mixture containing the formic acid-amine adduct, the tertiary amine, the high-boiling polar solvent and the catalyst.
  • the reaction mixture is worked up according to WO 2010/149507 according to the following steps:
  • a disadvantage of the process of WO 2010/149507 is that the separation of the catalyst despite phase separation (step 1)) and extraction (step 2)) is not always completely successful, so that traces of catalyst contained in the raffinate in the thermal cracking in the distillation column in Step 3) can catalyze the cleavage of the formic acid-amine adduct to carbon dioxide and hydrogen and the tertiary amine. It is also disadvantageous that esterification of the formic acid formed with the high-boiling polar solvents (diols and polyols) occurs in the thermal cleavage of the formic acid-amine adduct in the distillation column. This leads to a reduction in the yield of the target product formic acid.
  • the object of the present invention was to provide a process for the preparation of formic acid by hydrogenation of carbon dioxide, which does not have the disadvantages of the prior art or only to a significantly reduced extent and which leads to concentrated formic acid in high yield and high purity , Furthermore, the method should allow a simpler process control, as described in the prior art, in particular a simpler process concept for working up the discharge from the hydrogenation reactor, simpler process steps, a smaller number of process stages or simpler apparatuses. Furthermore, the method should also be able to be carried out with the lowest possible energy consumption and consumption of additives such as inhibitors.
  • Solvent selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol and water and at least one tertiary amine of the general formula (A1)
  • R 1 , R 2 , R 3 independently represent an unbranched or branched, acyclic or cyclic, aliphatic, araliphatic or aromatic radical each having 1 to 16 carbon atoms, wherein individual carbon atoms independently of one another by a hetero group selected from the groups -O- and > N-substituted and two or all three radicals can also be linked together to form a chain comprising at least four atoms, in the presence of at least one complex catalyst which contains at least one element selected from groups 8, 9 and 10 of the Periodic Table, in a hydrogenation reactor to obtain, optionally after addition of water, a biphasic hydrogenation mixture (H) comprising an upper phase (01) containing the at least one complex catalyst and the at least one tertiary amine (A1), and a lower phase (U 1) the at least one polar solvent,
  • H biphasic hydrogenation mixture
  • step (b1) phase separation of the hydrogenation mixture (H) obtained in step (a) in a first phase separation device into the upper phase (01) and the lower phase (U 1), or
  • step (b2) extraction of the at least one complex catalyst from the hydrogen mixture (H) obtained in step (a) in an extraction unit with an extractant containing the at least one tertiary amine (A1) to obtain a raffinate (R1) containing the at least one formic acid amine Adduct (A2) and the at least one polar solvent and an extract (E1) containing the at least one tertiary amine (A1) and the at least one complex catalyst or
  • step (b3) phase separation of the hydrogenation mixture (H) obtained in step (a) in a first phase separation device into the upper phase (01) and the lower phase (U 1) and extraction of the residues of the at least one complex catalyst from the lower phase (U 1) in one
  • Extraction unit comprising an extractant containing the at least one tertiary amine (A1) to obtain a raffinate (R2) containing the at least one formic acid-amine adduct (A2) and the at least one polar solvent and an extract (E2) containing the at least one tertiary amine (A1) and the radicals of the at least one complex catalyst, (c) separating the at least one polar solvent from the lower phase (U 1), from the raffinate (R1) or from the raffinate (R2) in a first distillation apparatus to obtain a distillate (D1) containing the at least one polar solvent which is present in the hydrogenation reactor is recycled in step (a), and a biphasic bottom mixture (S1) comprising an upper phase (02) containing the at least one tertiary amine (A1), and a lower phase (U2) containing the at least one formic acid amine Contains adduct (A2),
  • step (D) optionally working up of the bottom mixture (S1) obtained in step (c) by phase separation in a second phase separation device in the
  • step (e) cleavage of the at least one formic acid-amine adduct (A2) contained in the bottom mixture (S1) or, if appropriate, in the bottom phase (U2) in a thermal splitting unit to give the at least one tertiary amine (A1) which is the hydrogenation reactor in step (a) and formic acid discharged from the thermal cleavage unit, immediately before and / or during step (c) of the lower phase (U 1), the
  • Raffinate (R1) or the raffinate (R2) carbon monoxide is added and / or immediately before and / or during step (e) the bottom mixture (S1) or optionally the lower phase (U2) carbon monoxide is added.
  • the process according to the invention makes it possible to recycle a large part of the complex catalyst into the hydrogenation in its active form, so that only small amounts of inhibitor have to be added and thus only a small part of the complex catalyst has to be reactivated after its inhibition.
  • the complex catalyst inhibited by thermal decomposition by carbon monoxide can be recycled back into the hydrogenation in step (a) via the amine phase from the thermal splitting unit in step (e), where it is reactivated under the reaction conditions.
  • the entire bottom of the thermal cleavage need not be recycled in step (a) in order to avoid catalyst losses.
  • the separation of the polar solvent used according to the invention also prevents esterification of the formic acid obtained in the thermal splitting unit in step (e), which likewise leads to an increase in the yield of formic acid.
  • the use of the polar solvents according to the invention leads to an increase in the concentration of the formic acid-amine adduct (A2) in the hydrogenation mixture (H) obtained in step (a) compared to the high-boiling polar solvents used in WO2010 / 149507. leads. This allows the use of smaller reactors, which in turn leads to a cost savings.
  • step and “process step” are used synonymously below.
  • a reaction mixture (Rg) is reacted in process step (a), the carbon dioxide, hydrogen, at least one complex catalyst containing at least one element selected from groups 8, 9 and 10 of the periodic table, at least one polar solvent selected from Group consisting of methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol and water and at least one tertiary amine of the general formula (A1).
  • the carbon dioxide used in process step (a) can be solid, liquid or gaseous. It is also possible to use gas mixtures containing large quantities of carbon dioxide, provided they are substantially free of carbon monoxide (volume fraction of ⁇ 1% CO).
  • the hydrogen used in the hydrogenation of carbon dioxide in process step (a) is generally gaseous.
  • Carbon dioxide and hydrogen may also contain inert gases, such as nitrogen or noble gases.
  • inert gases such as nitrogen or noble gases.
  • their content is advantageously below 10 mol% based on the total amount of carbon dioxide and hydrogen in the hydrogenation reactor.
  • quantities may also be tolerable, they generally require the use of a higher pressure in the reactor, requiring further compression energy.
  • Carbon dioxide and hydrogen can be fed to process stage (a) as separate streams. It is also possible to use a mixture containing carbon dioxide and hydrogen in process step (a).
  • tertiary amine (A1) is used in process step (a) in the hydrogenation of carbon dioxide.
  • tertiary amine (A1) is understood as meaning both one (1) tertiary amine (A1) and mixtures of two or more tertiary amines (A1).
  • the tertiary amine (A1) used in the process according to the invention is preferably selected or matched with the polar solvent such that the hydrogenation mixture (H) obtained in process step (a) is at least biphasic, if appropriate after the addition of water.
  • the hydrogenation mixture (H) contains an upper phase (01) containing the at least one complex catalyst and the at least one tertiary amine (A1), and a lower phase (U 1) containing the at least one polar solvent, residues of the complex catalyst and at least one formic acid Amine adduct (A2).
  • the tertiary amine (A1) should be enriched in the upper phase (01), i. the upper phase (01) should contain the main part of the tertiary amine (A1).
  • enriched or "main part” with respect to the tertiary amine (A1) is a weight fraction of the free tertiary amine (A1) in the upper phase (01) of> 50% based on the total weight of the free tertiary Amine (A1) in the liquid phases, ie the upper phase (01) and the lower phase (U 1) in the hydrogenation mixture (H) to understand.
  • free tertiary amine (A1) is meant the tertiary amine (A1) which is not bound in the form of the formic acid-amine adduct (A2).
  • the weight fraction of the free tertiary amine (A1) in the upper phase (01) is preferably> 70%, in particular> 90%, in each case based on the total weight of the free tertiary amine (A1) in the upper phase (01) and the lower phase ( U 1) in the hydrogenation mixture (H).
  • the selection of the tertiary amine (A1) is generally carried out by a simple experiment in which the phase behavior and the solubility of the tertiary amine (A1) in the liquid phases (upper phase (01) and lower phase (U1)) under the process conditions in the process stage (a) be determined experimentally.
  • non-polar solvents such as aliphatic, aromatic or araliphatic solvents may be added to the tertiary amine (A1).
  • Preferred non-polar solvents are, for example, octane, toluene and / or xylenes (o-xylene, m-xylene, p-xylene).
  • the preferred tertiary amine to be used in the process according to the invention is an amine of the general formula
  • NR 1 R 2 R 3 in which the radicals R 1 , R 2 , R 3 are identical or different and independently of one another are an unbranched or branched, acyclic or cyclic, aliphatic, araliphatic or aromatic radical having in each case 1 to 16 carbon atoms, preferably 1 to 12 carbon atoms, wherein individual carbon atoms can be substituted independently of one another by a hetero group selected from the groups -O- and> N- and two or all three radicals to form a chain comprising at least four atoms in each case also connected to each other can.
  • a tertiary amine of the general formula (A1) is used, with the proviso that the total number of carbon atoms is at least 9.
  • Suitable tertiary amines (A1) include:
  • triphenylamine methyldiphenylamine, ethyldiphenylamine, propyldiphenylamine, butyldiphenylamine, 2-ethylhexyldiphenylamine, dimethylphenylamine, diethylphenylamine, dipropylphenylamine, dibutylphenylamine, bis (2-ethylhexyl ) - phenylamine, tribenzylamine, methyl-dibenzylamine, ethyl-dibenzylamine and theirs by one or more methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl or 2-methyl-2- propyl groups substituted derivatives.
  • Nd-bis-C 1-4 -alkyl-piperidines N, N-di-d-bis-C 1-4 -alkyl-piperazines, N-crib-C 12 -alkyl-pyrrolidones, NC-bis-C 1-4 -alkyl-imidazoles and theirs one or more methyl.
  • DBU 1, 8-diazabicyclo [5.4.0] undec-7-ene
  • DABCO 1, 4-diazabicyclo [2.2.2] octane
  • tropane N-methyl-8-azabicyclo [3.2 .1] octane
  • garnetane N-methyl-9-azabicyclo [3.3.1] nonane
  • 1-azabicyclo [2.2.2] octane quinuclidine
  • mixtures of two or more different tertiary amines (A1) can also be used.
  • tertiary amine (A1) is an amine in which the radicals R 1 , R 2 , R 3 are independently selected from the group C to C 12 alkyl, C 5 - to C 8 - Cycloalkyl, benzyl and phenyl.
  • a tertiary amine (A1) is a saturated amine, d. H. only single bond-containing amine.
  • An especially suitable amine in the process according to the invention is a tertiary amine of the general formula (A1) in which the radicals R 1 , R 2 , R 3 are independently selected from the group C 5 - to C 8 -alkyl, in particular tri -n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine,
  • one (1) tertiary amine of the general formula (A1) is used.
  • the tertiary amine used is an amine of the general formula (A1) in which the radicals R 1 , R 2 and R 3 are selected independently of one another from C 5 - and C 6 -alkyl.
  • tri-n-hexylamine is used as the tertiary amine of the general formula (A1).
  • the tertiary amine (A1) in the process according to the invention is preferably liquid in all process stages. However, this is not a mandatory requirement. It would also be sufficient if the tertiary amine (A1) were dissolved at least in suitable solvents.
  • Suitable solvents are in principle those which are chemically inert with respect to the hydrogenation of carbon dioxide, in which the tertiary amine (A1) and the catalyst dissolve well and in which, conversely, the polar solvent and the formic acid-amine adduct (A2) dissolve poorly ,
  • chemically inert, nonpolar solvents such as aliphatic, aromatic or araliphatic hydrocarbons, such as octane and higher alkanes, toluene, xylenes.
  • At least one polar solvent is selected in process step (a) in the hydrogenation of carbon dioxide from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1 - propanol and water used.
  • polar solvent is understood to mean both one (1) polar solvent and mixtures of two or more polar solvents.
  • the polar solvent used in the process according to the invention is preferably selected or matched with the tertiary amine (A1) so that it preferably meets the following criteria with regard to the phase behavior in the hydrogenation reactor in process step (a):
  • the polar solvent should preferably be selected such that the hydrogenation mixture (H) obtained in process step (a), if appropriate after the addition of water, is at least biphasic.
  • the polar solvent should be enriched in the lower phase (U 1), ie the lower phase (U 1) should contain the main part of the polar solvent.
  • enriched or “main part” with respect to the polar solvent is a weight fraction of the polar solvent in the lower phase (U 1) of> 50%, based on the total weight of the polar solvent in the liquid phases (upper phase ( 01) and lower phase (U 1)) in the hydrogenation reactor to understand.
  • the weight fraction of the polar solvent in the lower phase (U 1) is preferably> 70%, in particular> 90%, in each case based on the total weight of the polar solvent in the upper phase (01) and the lower phase (U 1).
  • the selection of the polar solvent satisfying the above criteria is generally accomplished by a simple experiment in which the phase behavior and the solubility of the polar solvent in the liquid phases (upper phase (01) and lower phase (U 1)) under the process conditions in Process step (a) are determined experimentally.
  • the polar solvent may be a pure polar solvent or a mixture of two or more polar solvents as long as the polar solvent or mixture of polar solvents meets the above-described phase behavior and solubility criteria in the upper phase (01) and the above Subphase (U 1) in the hydrogenation reactor in process step (a).
  • step (a) first of all a single-phase hydrogenation mixture is obtained, which is converted into the biphasic hydrogenation mixture (H) by the addition of water.
  • the biphasic hydrogenation mixture (H) is obtained directly in step (a).
  • the biphasic hydrogenation mixture (H) obtained in this embodiment can be directly fed to the work-up of step (b). It is also possible to additionally add Waser to the biphasic hydrogenation mixture (H) before further processing in step (b). This can lead to an increase of the distribution coefficient P K.
  • the polar solvent used is a mixture of alcohol (selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol and 2-methyl-1-propanol) and water is, the ratio of alcohol to water is chosen so that together with the formic acid-amine adduct (A2) and the tertiary amine (A1) an at least two-phase hydrogenation mixture (H) containing the upper phase (01) and the lower phase (U 1) trains.
  • alcohol selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol and 2-methyl-1-propanol
  • the ratio of alcohol to water is chosen so that together with the formic acid-amine adduct (A2) and the tertiary amine (A1) an at least two-phase hydrogenation mixture (H) containing the upper phase (01) and the lower phase (U 1) trains.
  • the polar solvent used is water, methanol or a mixture of water and methanol.
  • diols and their formic acid esters, polyols and their formic acid esters, sulfones, sulfoxides and open-chain or cyclic amides as the polar solvent is not preferred. In a preferred embodiment, these polar solvents are not contained in the reaction mixture (Rg).
  • the molar ratio of the polar solvent or solvent mixture used in the process according to the invention in process step (a) to the tertiary amine (A1) used is generally 0.5 to 30 and preferably 1 to 20.
  • the complex catalyst used in the process according to the invention in process step (a) for the hydrogenation of carbon dioxide comprises at least one element selected from groups 8, 9 and 10 of the Periodic Table (IUPAC nomenclature).
  • Groups 8, 9 and 10 of the Periodic Table include Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt.
  • one (1) complex catalyst or a mixture of two or more complex catalysts can be used.
  • one (1) catalyst is used.
  • “complex catalyst” is understood to mean both one (1) complex catalyst and mixtures of two or more complex catalysts.
  • the complex catalyst contains at least one element selected from the group consisting of Ru, Rh, Pd, Os, Ir and Pt, more preferably at least one element selected from the group consisting of Ru, Rh and Pd.
  • the complex catalyst Ru contains.
  • a complex-type compound of the above-mentioned elements is preferably used.
  • the reaction in process step (a) is preferably carried out homogeneously catalyzed.
  • homogeneously catalyzed means that the catalytically active part of the complex catalyst is at least partially dissolved in the liquid reaction medium.
  • at least 90% of the complex catalyst employed in process step (a) is dissolved in the liquid reaction medium, more preferably at least 95%, most preferably more than 99%, most preferably Complex catalyst completely dissolved in the liquid reaction medium before (100%), each based on the total amount of complex catalyst present in the liquid reaction medium.
  • the amount of the metal components of the complex catalyst in process step (a) is generally from 0.1 to 5000 ppm by weight, preferably from 1 to 800 ppm by weight and more preferably from 5 to 800 ppm by weight, based in each case on the entire liquid reaction mixture (Rg) in the hydrogenation reactor.
  • the complex catalyst is selected so that it is enriched in the upper phase (01), ie the upper phase (01) contains the main part of the complex catalyst.
  • a distribution coefficient P K > 1.5 is preferred, and a distribution coefficient P K > 4 is particularly preferred.
  • the complex catalyst is generally selected by a simple experiment in which the phase behavior and the solubility of the complex catalyst in the liquid phases (upper phase (01) and lower phase (U 1)) under the process conditions in process step (a).
  • complex catalysts preferably homogeneous complex catalysts, in particular an organometallic complex compound containing an element from the 8th, 9th or 10th group of the periodic table and at least one phosphine group with at least one unbranched or branched, acyclic or cyclic, aliphatic radical having 1 to 12 carbon atoms, wherein individual carbon atoms may also be substituted by> P-.
  • organometallic complex compound containing an element from the 8th, 9th or 10th group of the periodic table and at least one phosphine group with at least one unbranched or branched, acyclic or cyclic, aliphatic radical having 1 to 12 carbon atoms, wherein individual carbon atoms may also be substituted by> P-.
  • radicals such as, for example, -CH 2 -C 6 HH are thus also included.
  • Suitable radicals are, for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 1- (2-methyl) propyl, 2- (2-methyl) propyl, 1-pentyl, 1-hexyl, 1 - Heptyl, 1-octyl, 1 -nonyl, 1-decyl, 1-undecyl, 1-dodecyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl, methylcyclopentyl, methylcyclohexyl, 1- (2-methyl) -pentyl, 1- (2-ethyl ) -hexyl, 1- (2-propyl) heptyl and norbornyl.
  • the unbranched or branched, acyclic or cyclic, aliphatic radical preferably contains at least 1 and preferably not more than 10 carbon atoms. In the case of an exclusively cyclic radical in the above-mentioned sense, the number of carbon atoms is 3 to 12 and preferably at least 4 and preferably at most 8 carbon atoms.
  • Preferred radicals are ethyl, 1-butyl, sec-butyl, 1-octyl and cyclohexyl.
  • the phosphine group can contain one, two or three of the above-mentioned unbranched or branched, acyclic or cyclic, aliphatic radicals. These can be the same or different.
  • the phosphine group contains three of the above-mentioned unbranched or branched, acyclic or cyclic, aliphatic radicals, with particular preference, all three radicals are the same.
  • Preferred phosphines are P (nC n H 2n + i) 3 with n being 1 to 10, more preferably tri-n-butylphosphine, tri-n-octylphosphine and 1, 2-bis (dicyclohexalphosphino) ethane.
  • acyclic or cyclic, aliphatic radicals individual carbon atoms may also be substituted by> P-.
  • multidentate for example, bidentate or tridentate phosphine ligands are also included. These preferably contain the
  • the phosphine group contains radicals other than the abovementioned unbranched or branched, acyclic or cyclic, aliphatic radicals, these generally correspond to those which are customarily used in the case of phosphine ligands for organometallic complex catalysts.
  • acyclic or cyclic, aliphatic radicals these generally correspond to those which are customarily used in the case of phosphine ligands for organometallic complex catalysts.
  • phenyl, tolyl and xylyl examples of its called phenyl, tolyl and xylyl.
  • the organometallic complex compound may contain one or more, for example two, three or four, of the abovementioned phosphine groups having at least one unbranched or branched, acyclic or cyclic, aliphatic radical.
  • the remaining ligands of the organometallic complex may be of different nature. Examples which may be mentioned are hydride, fluoride, chloride, bromide, iodide, formate, acetate, propionate, carboxylate, acetylacetonate, carbonyl, DMSO, hydroxide, trialkylamine, alkoxide.
  • the homogeneous catalysts can be used both directly in their active form and starting from customary standard complexes such as [M (p-cymene) Cl 2 ] 2 , [M (benzene) Cl 2 ] n , [M (COD) (allyl)], [MCI 3 ⁇ H 2 O], [M (acetylacetonate) 3 ], [M (COD) Cl 2 ] 2 , [M (DMSO) 4 Cl 2 ] with M being the same element from the 8th, 9th or 10th Group of the periodic table with the addition of the corresponding or the corresponding phosphine ligands are produced only under reaction conditions.
  • customary standard complexes such as [M (p-cymene) Cl 2 ] 2 , [M (benzene) Cl 2 ] n , [M (COD) (allyl)], [MCI 3 ⁇ H 2 O], [M (acetylacetonate) 3 ], [M (COD) Cl 2 ] 2
  • Homogeneous complex catalysts which are preferred in the process according to the invention are selected from the group consisting of [Ru (P n Bu 3 ) 4 (H) 2 ], [Ru (P n octyl 3 ) 4 (H) 2 ], [Ru (P n Bu 3 ) 2 (1, 2-bis (dicyclohexylphosphino) ethane) (H) 2], [Ru (P n-octyl 3) 2 (1, 2-bis (dicyclohexylphosphino) ethane) (H) 2], [Ru (PEt 3 ) 4 (H) 2 ]
  • TOF values (turn-over-frequency) of greater than 1000 r.sup.- 1 can be achieved.
  • the hydrogenation of carbon dioxide in process step (a) is preferably carried out in the liquid phase at a temperature in the range of 20 to 200 ° C and a total pressure in the range of 0.2 to 30 MPa abs.
  • the temperature is at least 30 ° C and more preferably at least 40 ° C and preferably at most 150 ° C, more preferably at most 120 ° C and most preferably at most 80 ° C.
  • the total pressure is preferably at least 1 MPa abs and more preferably at least 5 MPa abs and preferably at most 20 MPa abs.
  • the hydrogenation is carried out in process step (a) at a temperature in the range of 40 to 80 ° C and a pressure in the range of 5 to 20 MPa abs.
  • the partial pressure of the carbon dioxide in process step (a) is generally at least 0.5 MPa and preferably at least 2 MPa and generally at most 8 MPa.
  • the hydrogenation is carried out in Process step (a) at a partial pressure of carbon dioxide in the range of 2 to 7.3 MPa.
  • the partial pressure of the hydrogen in process step (a) is generally at least 0.5 MPa and preferably at least 1 MPa and generally at most 25 MPa and preferably at most 15 MPa.
  • the hydrogenation in process step (a) is carried out at a partial pressure of the hydrogen in the range of 1 to 15 MPa.
  • the molar ratio of hydrogen to carbon dioxide in the reaction mixture (Rg) in the hydrogenation reactor is preferably 0, 1 to 10 and more preferably 1 to 3.
  • the molar ratio of carbon dioxide to tertiary amine (A1) in the reaction mixture (Rg) in the hydrogenation reactor is preferably 0, 1 to 10 and more preferably 0.5 to 3.
  • reactors which are suitable for gas / liquid reactions under the given temperature and the given pressure can be used as hydrogenation reactors.
  • Suitable standard reactors for gas-liquid reaction systems are, for example, in KD Henkel, "Reactor Types and Their Industrial Applications", in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH Verlag GmbH & Co. KGaA, DOI: 10.1002 / 14356007.b04_087, Chapter 3.3 "Reactors for gas-liquid reactions" indicated.
  • stirred tank reactors tubular reactors or bubble column reactors.
  • the hydrogenation of carbon dioxide can be carried out batchwise or continuously in the process according to the invention.
  • the reactor In the batchwise procedure, the reactor is equipped with the desired liquid and optionally solid feedstocks and auxiliaries, and then carbon dioxide and the polar solvent are pressed to the desired pressure at the desired temperature. After the end of the reaction, the reactor is normally depressurized and the two liquid phases formed are separated from one another. In the continuous mode of operation, the feedstocks and auxiliaries, including carbon dioxide and hydrogen, are added continuously. Accordingly, the liquid phases are continuously discharged from the reactor, so that the liquid level in the reactor remains the same on average. Preference is given to the continuous hydrogenation of carbon dioxide.
  • the average residence time of the components in the hydrogenation reactor contained in the reaction mixture (Rg) is generally from 5 minutes to 5 hours.
  • a hydrogenation mixture (H) is obtained in process step (a) which contains the complex catalyst, the polar solvent, the tertiary amine (A1) and the at least one formic acid-amine adduct (A2).
  • formic acid-amine adduct (A2) is understood as meaning both one (1) formic acid-amine adduct (A2) and mixtures of two or more formic acid-amine adducts (A2) or more formic acid-amine adducts (A2) are obtained in process step (a), if in the reaction mixture used (Rg) two or more tertiary amines (A1) are used.
  • a reaction mixture (Rg) is used in process step (a) which comprises a (1) tertiary amine (A1), a hydrogenation mixture (H) being obtained which comprises one (1) formic acid amine.
  • Adduct (A2) contains.
  • a reaction mixture (Rg) is used in process step (a) which comprises tri-n-hexylamine as the tertiary amine (A1) to give a hydrogenation mixture (H) which comprises the formic acid amine.
  • Adduct of tri-n-hexylamine and formic acid corresponds to the following formula (A3)
  • x is in the range of 0.4 to 5.
  • the factor X indicates the average composition of the formic acid-amine adduct (A2) and (A3), respectively. the ratio of bound tertiary amine (A1) to bound formic acid in the formic acid-amine adduct (A2) or (A3).
  • the factor x can be determined, for example, by determining the formic acid content by acid-base titration with an alcoholic KOH solution against phenolphthalein. In addition, a determination of the factor x, by determining the amine content by gas chromatography is possible.
  • the exact composition of the formic acid-amine adduct (A2) or (A3) depends on many parameters, such as the concentrations of formic acid and tertiary amine (A1), the pressure, the temperature and the presence and nature of other components, in particular of the polar solvent. Therefore, the composition of the formic acid amine adduct (A2) or (A3), ie the factor x ,, can also change over the individual process stages.
  • a formic acid-amine adduct (A2) or (A3) with a higher formic acid content generally forms, the excess bound tertiary amine (A1) being formed from the formic acid-amine adduct (A2 ) is split off and forms a second phase.
  • a formic acid-amine adduct (A2) or (A3) is generally obtained in which x is in the range from 0.4 to 5, preferably in the range from 0.7 to 1.6 ,
  • the formic acid-amine adduct (A2) is enriched in the lower phase (U 1), i. the lower phase (U 1) contains the major part of the formic acid-amine adduct.
  • the term "enriched" or "main part" with respect to the formic acid-amine adduct (A2) refers to a weight proportion of the formic acid-amine adduct (A2) in the lower phase (U 1) of> 50% to understand the total weight of the formic acid-amine adduct (A2) in the liquid phases (upper phase (01) and lower phase (U 1)) in the hydrogenation reactor.
  • the weight fraction of the formic acid-amine adduct (A2) in the lower phase (U 1) is preferably> 70%, in particular> 90%, in each case based on the total weight of the formic acid-amine adduct (A2) in the upper phase (01 ) and the lower phase (U 1).
  • the hydrogenation mixture (H) obtained in the hydrogenation of carbon dioxide in process step (a) preferably has two liquid phases and is further worked up in process step (b) according to one of the steps (b1), (b2) or (b3).
  • the hydrogenation mixture (H) according to step (b1) is further worked up.
  • the invention therefore also provides a process for the preparation of formic acid, comprising the steps
  • reaction mixture comprising carbon dioxide, hydrogen, at least one polar solvent selected from the group consisting of methanol,
  • R 1 , R 2 , R 3 independently represent an unbranched or branched, acyclic or cyclic, aliphatic, araliphatic or aromatic radical each having 1 to 16 carbon atoms, wherein individual carbon atoms independently of one another by a hetero group selected from the groups -O- and > N-substituted and two or all three radicals can also be linked together to form a chain comprising at least four atoms, in the presence of at least one complex catalyst which contains at least one element selected from groups 8, 9 and 10 of the Periodic Table, in a hydrogenation reactor to obtain, optionally after addition of water, a biphasic hydrogenation mixture (H) comprising an upper phase (01) containing the at least one complex catalyst and the at least one tertiary amine (A1), and a lower phase (U 1) the at least one polar solvent, residues of at least one n complex catalyst and at least one formic acid-amine adduct of the general formula (A2),
  • H biphasic hydrogen
  • R 1 , R 2 , R 3 have the abovementioned meanings, phase separation of the hydrogenation mixture (H) obtained in step (a) in a first phase separation device into the upper phase (01) and the lower phase (U 1), (c) separating the at least one polar solvent from the lower phase (U 1) in a first distillation apparatus to obtain a distillate (D1) containing the at least one polar solvent which is recycled to the hydrogenation reactor in step (a) and a biphasic mixed slurry (S1) comprising an upper phase (02) containing the at least one tertiary amine (A1), and a lower phase (U2) containing the at least one formic acid-amine adduct (A2),
  • step (d) optionally working up of the first bottoms mixture (S1) obtained in step (c) by phase separation in a second phase separation device into the upper phase (02) and the lower phase (U2),
  • step (e) cleavage of the at least one formic acid-amine adduct (A2) contained in the bottom mixture (S1) or, if appropriate, in the bottom phase (U2) in a thermal splitting unit to give the at least one tertiary amine (A1) which is the hydrogenation reactor in step (a) and formic acid discharged from the thermal cleavage unit, carbon monoxide being added immediately before and / or during step (c) to the lower phase (U 1) and / or immediately before and / or during step (e ) is added to the bottom mixture (S1) or optionally the lower phase (U2) carbon monoxide.
  • the hydrogenation mixture (H) obtained in process step (a) is further worked-up in a first phase separation by phase separation to obtain a lower phase (U 1) comprising the at least one formic acid-amine adduct (A2) containing at least one polar solvent and radicals the at least one complex catalyst and an upper phase (01) comprising the at least one complex catalyst and the at least one tertiary amine (A1).
  • the upper phase (01) is recycled to the hydrogenation reactor.
  • the lower phase (U 1) is supplied in a preferred embodiment of the first distillation apparatus in process step (c).
  • the phase separation may take place, for example, after relaxation to about or near atmospheric pressure and cooling of the liquid hydrogenation mixture, for example at about or near ambient temperature.
  • the polar solvent and the tertiary amine (A1) can be selected such that the separation of the lower phase (U 1) enriched with the formic acid-amine adducts (A2) and the polar solvent from the tertiary amine (A1 ) and complex catalyst-enriched upper phase (01) and the return of the upper phase (01) to the hydrogenation reactor at a pressure of 1 to 30 MPa abs can be carried out.
  • the pressure is preferably at most 15 MPa abs. It is thus possible, without prior relaxation, to separate both liquid phases (upper phase (01) and lower phase (U 1)) in the first phase separation device and to recirculate the upper phase (01) to the hydrogenation reactor without appreciable pressure increase.
  • the hydrogenation reactor functions simultaneously as a first phase separation device and the process steps (a) and (b1) are both in the Hydrogenation reactor performed.
  • the upper phase (01) remains in the hydrogenation reactor and the lower phase (U 1) is fed to the first distillation apparatus in process stage (c).
  • the process according to the invention is carried out in such a way that the pressure and the temperature in the hydrogenation reactor and in the first phase separator are the same or approximately the same, whereby a pressure difference of up to +/- 0.5 MPa or approximately equal to a temperature difference of up to +/- 10 ° C is understood.
  • the hydrogenation mixture (H) is worked up further in step (b3).
  • the invention therefore also provides a process for the preparation of formic acid, comprising the steps
  • Solvent selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol and water and at least one tertiary amine of the general formula (A1)
  • R 1 , R 2 , R 3 independently represent an unbranched or branched, acyclic or cyclic, aliphatic, araliphatic or aromatic radical each having 1 to 16 carbon atoms, wherein individual carbon atoms independently of one another by a hetero group selected from the groups -O- and > N-substituted and two or all three radicals may also be linked together to form a chain comprising at least four atoms each, in the presence of at least one complex catalyst containing at least one element selected from Groups 8, 9 and 10 of the Periodic Table, in a hydrogenation to obtain, optionally after addition of water, a biphasic hydrogenation mixture (H) containing an upper phase (01) containing the at least one complex catalyst and the at least one tertiary amine (A1), and a lower phase (U 1) containing the at least one polar solvent, residues of the at least one complex catalyst and at least one formic acid-amine adduct of the general formula (A2),
  • H biphas
  • R 1 , R 2 , R 3 have the meanings given above,
  • step (b3) Phase separation of the hydrogenation mixture (H) obtained in step (a) in a first phase separation apparatus into the upper phase (01) and the lower phase (U 1) and extraction of the residues of the at least one complex catalyst from the lower phase (U 1) in an extraction unit with an extractant containing the at least one tertiary amine (A1) to obtain a raffinate (R2) containing the at least one formic acid amine
  • step (c) separating the at least one polar solvent from the raffinate (R2) in a first distillation apparatus to obtain a distillate (D1) containing the at least one polar solvent which is recycled to the hydrogenation reactor in step (a) and a biphasic mixture of bottoms ( S1) an upper phase (02) containing the at least one tertiary amine (A1) and a lower phase (U2) containing the at least one formic acid-amine adduct (A2),
  • A2 formic acid-amine adduct
  • the hydrogenation mixture (H) obtained in process step (a) is separated into the lower phase (U 1) and the upper phase (01), which is recycled to the hydrogenation reactor, as described above for process step (b1) in the first phase separation device.
  • the statements and preferences made for process step (b1) apply correspondingly to process step (b3).
  • the hydrogenation reactor simultaneously acts as the first phase separation device. The upper phase (01) then remains in the hydrogenation reactor and the lower phase (U 1) is fed to the extraction unit.
  • the lower phase (U 1) obtained after phase separation is subsequently subjected in an extraction unit to extraction with at least one tertiary amine (A1) as extractant to remove the residues of the complex catalyst to obtain a raffinate (R2) containing the at least one formic acid-amine adduct (A2) and the at least one polar solvent and an extract (E2) containing the at least one tertiary amine (A1) and the radicals of the complex catalyst.
  • the same tertiary amine (A1) used in process step (a) in the reaction mixture (Rg) is used as extractant, so that the statements and preferences with respect to the tertiary amine (A) for the process step (a) A1) apply correspondingly to process step (b3).
  • the extract (E2) obtained in process step (b3) is recycled in a preferred embodiment to the hydrogenation reactor in process step (a). This allows efficient recovery of the expensive complex catalyst.
  • the raffinate (R2) is supplied in a preferred embodiment of the first distillation apparatus in process step (c).
  • the extractant used in process step (b3) is preferably the tertiary amine (A1) which is obtained in the thermal splitting unit in process step (e).
  • the tertiary amine (A1) obtained in the thermal splitting unit in process step (e) is recycled to the extraction unit in process step (b3).
  • the extraction is carried out in process step (b3) generally at temperatures in the range of 30 to 100 ° C and pressures in the range of 0, 1 to 8 MPa.
  • the extraction can also be carried out under hydrogen pressure.
  • the extraction of the complex catalyst can be carried out in any suitable apparatus known to the person skilled in the art, preferably in countercurrent extraction columns, mixer-settler cascades or combinations of mixer-settler cascades and countercurrent extraction columns.
  • fractions of individual components of the polar solvent from the subphase (U 1) to be extracted in the extraction agent, the tertiary amine (A1), are dissolved in addition to the complex catalyst. This is not a disadvantage for the process, since the already extracted amount of polar solvent does not have to be supplied to the solvent removal and thus may save evaporation energy.
  • the hydrogenation mixture (H) is further worked up according to step (b2).
  • the invention therefore also provides a process for the preparation of formic acid, comprising the steps (A) homogeneously catalyzed reaction of a reaction mixture (Rg) containing carbon dioxide, hydrogen, at least one polar solvent selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl 1-propanol and water and at least one tertiary amine of the general formula
  • R 1 , R 2 , R 3 independently represent an unbranched or branched, acyclic or cyclic, aliphatic, araliphatic or aromatic radical each having 1 to 16 carbon atoms, wherein individual carbon atoms independently of one another by a hetero group selected from the groups -O- and > N-substituted and two or all three radicals can also be linked together to form a chain comprising at least four atoms, in the presence of at least one complex catalyst which contains at least one element selected from groups 8, 9 and 10 of the Periodic Table, in a hydrogenation reactor to obtain, optionally after addition of water, a biphasic hydrogenation mixture (H) containing an upper phase (01) containing the at least one complex catalyst and the at least one tertiary amine (A1), and a lower phase (U1) containing the at least one polar solvent, residues of at least one Catalyst and at least one formic acid-amine adduct of the general formula (A2),
  • H bipha
  • X is in the range of 0.4 to 5 and
  • R 1 , R 2 , R 3 have the meanings given above, (b2) extraction of the at least one complex catalyst from the hydrogenation mixture (H) obtained in step (a) in an extraction unit with an extractant containing the at least one tertiary amine (A1) to obtain a raffinate (R1) containing the at least one formic acid amine Adduct (A2) and the at least one polar solvent and an extract (E1) containing the at least one tertiary amine (A1) and the at least one complex catalyst
  • step (c) separating the at least one polar solvent from the raffinate (R1) in a first distillation apparatus to obtain a distillate (D1) containing the at least one polar solvent which is recycled to the hydrogenation reactor in step (a) and a biphasic mixture ( S1) comprising an upper phase (02) containing the at least one tertiary amine (A1) and a lower phase (U2) containing the at least one formic acid-amine adduct (A2),
  • step (D) optionally working up of the bottom mixture (S1) obtained in step (c) by phase separation in a second phase separation device in the
  • the hydrogenation mixture (H) is in this case subjected in an extraction unit to extraction with at least one tertiary amine (A1) as extractant to remove the catalyst to obtain a raffinate (R1) containing the at least one formic acid-amine adduct (A2) and the at least a polar solvent and an extract (E1) containing the at least one tertiary amine (A1) and the at least one complex catalyst.
  • the same tertiary amine (A1) used in process step (a) in the reaction mixture (Rg) is used as extractant, so that the statements and preferences with respect to the tertiary amine (A) for the process step (a) A1) apply correspondingly to process step (b2).
  • the extract (E1) obtained in process step (b2) is recycled in a preferred embodiment to the hydrogenation reactor in process step (a). This allows efficient recovery of the expensive complex catalyst.
  • the raffinate (R1) is supplied in a preferred embodiment of the first distillation apparatus in process step (c).
  • the tertiary amine (A1) which is obtained in the thermal splitting unit in process step (e) is preferably used as extractant in process step (b2).
  • the tertiary amine (A1) obtained in the thermal splitting unit in process step (e) is recycled to the extraction unit in process step (b2).
  • the extraction is carried out in process step (b2) generally at temperatures in the range of 30 to 100 ° C and pressures in the range of 0, 1 to 8 MPa.
  • the extraction can also be carried out under hydrogen pressure.
  • the extraction of the complex catalyst can be carried out in any suitable apparatus known to the person skilled in the art, preferably in countercurrent extraction columns, mixer-settler cascades or combinations of mixer-settler cascades and countercurrent extraction columns.
  • the complex catalyst in addition to the complex catalyst also shares of individual components of the polar solvent from the hydrogenation mixture to be extracted (H) in the extractant, the tertiary amine (A1), dissolved.
  • H hydrogenation mixture
  • A1 tertiary amine
  • the inhibition of the complex catalyst with carbon monoxide may occur immediately before and / or during step (c) and / or immediately before and / or during step (e).
  • inhibition occurs exclusively immediately before and / or during step (c). In one embodiment, inhibition occurs exclusively immediately before and / or during step (e).
  • the addition of carbon monoxide occurs both immediately before and / or during step (c) and immediately before and / or during step (e).
  • the lower phase (U 1) obtained according to process stage (b1), the raffinate (R1) obtained according to process stage (b2) or the raffinate (R2) obtained according to process stage (b3) are carbon monoxide as inhibitor (Decomposition inhibitor) was added.
  • the workup of the hydrogenation mixture (H) according to the invention enables effective separation and recycling of the complex catalyst into the hydrogenation reactor in step (a), residues of the complex catalyst are still present in the lower phase (U 1) during the workup according to process step (b1).
  • the raffinate (R1) still contains traces of the complex catalyst.
  • the raffinate (R2) still contains traces of the complex catalyst.
  • the lower phase (U 1) which is obtained according to process step (b1), contains radicals of the complex catalyst in amounts of ⁇ 100 ppm, preferably ⁇ 80 ppm and in particular of ⁇ 60 ppm, in each case based on the total weight of the lower phase (U 1).
  • the raffinate (R1) obtained according to process step (b2) contains traces of the complex catalyst in amounts of ⁇ 30 ppm, preferably ⁇ 20 ppm and in particular ⁇ 10 ppm, in each case based on the total weight of the raffinate (R1).
  • the raffinate (R2) obtained according to process step (b3) contains traces of the complex catalyst in amounts of ⁇ 30 ppm, preferably ⁇ 20 ppm and in particular ⁇ 10 ppm, in each case based on the total weight of the raffinate (R2).
  • the cleavage of free formic acid, which is optionally contained in the lower phase (U 1), the raffinate (R 1) or the raffinate (R 2) or in the further work-up from the formic acid-amine adduct (A2) is formed by the radicals or catalyses traces of the complex catalyst.
  • the formic acid is split into carbon dioxide and hydrogen.
  • carbon monoxide is added as an inhibitor immediately before and / or during step (c).
  • the inhibitor is added either immediately before or during step (c). In a further embodiment of the present invention, the at least one inhibitor is added immediately before and during step (c). In a further embodiment, the at least one inhibitor is added only immediately before step (c). In another embodiment, the inhibitor is added only during step (c).
  • step (c) is understood as meaning addition of the inhibitor into the feed of the first distillation apparatus or directly into the first distillation apparatus.
  • the inhibitor converts the complex catalyst into an inactive form (inhibited complex catalyst).
  • at least one ligand of the complex catalyst is replaced by carbon monoxide.
  • Part of the ligands originally contained in the active complex catalyst is split off.
  • the cleaved ligands are after the inhibition in their free, ie not bound to the metal component of the complex catalyst form before (free ligands).
  • the cleavage of the formic acid-amine adduct (A2) or the free formic acid is prevented, since the complex catalyst in the presence of carbon monoxide (in its inhibited form) the cleavage of the formic acid-amine adduct (A2) or the free formic acid not can catalyze more.
  • this reaction can be reversed in the presence of the free ligands, whereby a regeneration of the inhibited complex catalyst is achieved.
  • carbon monoxide is split off from the inhibited complex catalyst and replaced by the free ligands, forming the active complex catalyst.
  • the regeneration can be carried out directly in the hydrogenation in step (a), when the inhibited catalyst is recycled via the free amine (upper phase (03)) in the hydrogenation. It is also possible to accelerate the regeneration in an upstream step by a thermal treatment of the inhibited catalyst.
  • carbon monoxide-containing gases can be used.
  • pure carbon monoxide with a content of 99 wt .-%, preferably 99.5 wt .-%, in particular 99.9 wt .-% is used, each based on the total weight of the gas stream used as inhibitor.
  • mixtures of carbon monoxide and water mustard so-called syngas or oxogas
  • the carbon monoxide content therein is preferably 10 to 90% by weight.
  • the carbon monoxide can also be run as a circulating stream by the carbon monoxide-containing exhaust gas from the distillation unit of the thermal splitting unit is used again for inhibition.
  • the gas stream used as inhibitor preferably consists of carbon monoxide.
  • the inhibitor is used in a molar ratio of 0.5 to 1000, preferably 1 to 30, based on the catalytically active metal component of the complex catalyst in the first distillation apparatus and / or the thermal cleavage unit.
  • step (c) the inhibited complex catalyst and the free ligands are preferably present in the upper phase (02) enriched.
  • the upper phase then contains the tertiary amine (A1) and the inhibited complex catalyst as well as the free ligands.
  • the carbon monoxide which is not bound to the metal component of the inhibited complex catalyst (free carbon monoxide) is discharged from the first distillation apparatus and can be used again to inhibit the catalyst.
  • step (e) apply mutatis mutandis to the inhibited complex catalyst for step (c).
  • the inhibitor is added either immediately before or during step (e). In a further embodiment of the present invention, the at least one inhibitor added immediately before and during step (e). In a further embodiment, the at least one inhibitor is added only immediately before step (e). In another embodiment, the inhibitor is added only during step (e).
  • "immediately before step (e)” is understood as meaning addition of the inhibitor into the feed of the thermal splitting unit or directly into the thermal splitting unit
  • the upper phase (03) then contains the tertiary amine (A1) and the inhibited complex catalyst as well as the free ligands of the complex catalyst, the complex catalyst inhibited by carbon monoxide can be converted via the upper phase (O). 03) from the thermal cleavage into the hydrogenation in step (a), whereby the free ligands of the complex catalyst according to the invention are selected such that they are present together with the inhibited complex catalyst preferably in the upper phase (03).
  • enriched for process step (e) is a distribution coefficient
  • enriched for process step (e) is a distribution coefficient
  • the distribution coefficient P F i_ (e) is preferably> 2 and particularly preferably> 5.
  • the carbon monoxide, which is not bound to the metal component of the inhibited complex catalyst (free carbon monoxide) is derived from the thermal Split unit discharged and can be used again to inhibit the catalyst.
  • the inhibited complex catalyst can be converted back into its active form in the absence of carbon monoxide (reactivation). It is believed that in this case the carbon monoxide bound to the metal component of the inhibited complex catalyst is split off and replaced by free ligands.
  • the reactivation of the inhibited complex catalyst can be carried out in one embodiment in process step (a). Here, the upper phase (03) from the thermal splitting unit in process step (a) is recycled.
  • the inhibited complex catalyst contained in the upper phase (03) is reactivated before recycling in step (a).
  • the inhibited complex catalyst is subjected to a thermal treatment in the absence of free carbon monoxide to convert the inhibited complex catalyst to the active form prior to recycling in step (a), thereby increasing the space-time yield in the hydrogenation.
  • the upper phase (03) is heated to a pressure of 10 mbar to 10 bar to 100 to 200 ° C. Separation of the polar solvent; Process step (c)
  • the polar solvent is separated off from the lower phase (U 1), from the raffinate (R 1) or from the raffinate (R 2) in a first distillation apparatus.
  • a distillate (D1) and a two-phase bottoms mixture (S1) are obtained.
  • the distillate (D1) contains the separated polar solvent and is recycled to the hydrogenation reactor in step (a).
  • the bottoms mixture (S1) contains the upper phase (02) containing the tertiary amine (A1) and a lower phase (U2) containing the formic acid-amine adduct (A2).
  • the polar solvent in the first distillation apparatus in process stage (c), the polar solvent is partly removed, so that the bottom mixture (S1) contains not yet separated polar solvent.
  • process step (c) for example, from 5 to 98% by weight of the polar solvent contained in the lower phase (U 1), in the raffinate (R 1) or in the raffinate (R 2), preferably 50 to 98% by weight, more preferably 80 to 98 wt .-% and particularly preferably 80 to 90 wt .-% are separated, in each case based on the total weight of the in the lower phase (U 1) in the raffinate (R1) or in the raffinate (R2) polar solvent.
  • the carbon monoxide serving as a decomposition inhibitor can be added in gaseous form either into the feed or directly into the first distillation apparatus.
  • the polar solvent is used in the first distillation apparatus in process stage (c) completely detached.
  • “completely separated off” is a separation of more than 98% by weight of the polar solvent present in the lower phase (U 1), in the raffinate (R 1) or in the raffinate (R 2), preferably more than 98.5 wt .-%, particularly preferably more than 99 wt .-%, in particular more than 99.5 wt .-%, understood, in each case based on the total weight of the in the lower phase (U 1), in the raffinate (R1) or in the raffinate (R2) contained polar solvent.
  • the distillate (D1) separated in the first distillation apparatus is recycled in a preferred embodiment to the hydrogenation reactor in step (a).
  • a mixture of one or more alcohols and water is used as the polar solvent, it is also possible to remove from the first distillation apparatus a low-water distillate (D1 wa ) and a water-rich distillate (D1 wr ).
  • the water-rich distillate (D1 wr ) contains more than 50 wt .-% of the water contained in the distillate (D1), preferably more than 70 wt .-%, especially more than 80 wt .-%, in particular more than 90 wt .-%
  • the low-water distillate (D1 wa ) contains less than 50 wt .-% of the water contained in the distillate D1, preferably less than 30 wt .-%, more preferably less than 20 wt .-%, in particular less than 10 wt .-%.
  • the low-water distillate (D1 wa ) is recycled to the hydrogenation reactor in step (a).
  • the water-rich distillate (D 1 wr ) is fed to the upper phase (01).
  • the separation of the polar solvent from the lower phase (U 1), the raffinate (R 1) or the raffinate (R 2) can be carried out, for example, in an evaporator or in a distillation unit consisting of evaporator and column, the column containing packings, fillers and / or trays filled, done.
  • the at least partial removal of the polar solvent preferably takes place at a bottom temperature at which no free formic acid is formed from the formic acid-amine adduct (A2) at a given pressure.
  • the factor x, of the formic acid-amine adduct (A2) in the first distillation apparatus is generally in the range of 0.4 to 3, preferably in the range of 0.6 to 1, 8, particularly preferably in the range of 0.7 to 1, 7.
  • the bottom temperature in the first distillation apparatus is at least 20 ° C, preferably at least 50 ° C and particularly preferably at least 70 ° C, and generally at most 210 ° C, preferably at most 190 ° C.
  • the temperature in the first distillation apparatus is generally in the range of 20 ° C to 210 ° C, preferably in the range of 50 ° C to 190 ° C.
  • the pressure in the first distillation apparatus is generally at least 0.001 MPa abs, preferably at least 0.005 MPa abs and more preferably at least 0.01 MPa abs and generally at most 1 MPa abs and preferably at most 0, 1 MPa abs.
  • the pressure in the first distillation apparatus is generally in the range of 0.0001 MPa abs to 1 MPa abs, preferably in the range of 0.005 MPa abs to 0.1 MPa abs and more preferably in the range of 0.01 MPa abs to 0.1 MPa abs.
  • the formic acid-amine adduct (A2) and free tertiary amine (A1) can be obtained in the bottom of the first distillation apparatus, since the removal of the polar solvent gives formic acid-amine adducts with a lower amine content ,
  • the bottom mixture (S1) contains, depending on the separated amount of the polar solvent, the formic acid-amine adduct (A2) and optionally the free tertiary amine (A1) formed in the bottom of the first distillation apparatus.
  • the bottoms mixture (S1) is further worked up in process step (d) for further work-up and then fed to process step (e). It is also possible to feed the bottoms mixture (S1) from process step (c) directly to process step (e).
  • the bottoms mixture (S1) obtained in step (c) can be separated in a second phase separation device into the upper phase (02) and the lower phase (U2).
  • the lower phase (U2) is then further worked up according to process step (e).
  • the upper phase (02) is recycled from the second phase separation device to the hydrogenation reactor in step (a).
  • the upper phase (02) is recycled from the second phase separation device to the extraction unit.
  • the statements and preferences for the first phase separation device apply accordingly.
  • the method according to the invention thus comprises the steps (a), (b1), (c), (d) and (e).
  • the method according to the invention comprises the steps (a), (b2), (c), (d) and (e).
  • the method according to the invention comprises the steps (a), (b3), (c), (d) and (e).
  • the method according to the invention comprises the steps (a), (b1), (c) and (e).
  • the method according to the invention comprises the steps (a), (b2), (c) and (e).
  • the method according to the invention comprises the steps (a), (b3), (c) and (e).
  • the method according to the invention consists of the steps (a), (b1), (c), (d) and (e).
  • the process according to the invention consists of the steps (a), (b2), (c), (d) and (e).
  • the process according to the invention consists of the steps (a), (b3), (c), (d) and (e).
  • the process according to the invention consists of the steps (a), (b3), (c), (d) and (e).
  • the process according to the invention consists of the steps (a), (b1), (c) and (e).
  • the process according to the invention consists of the steps (a), (b2), (c) and (e).
  • the process according to the invention consists of the steps (a), (b3), (c) and (e).
  • the formic acid-amine adduct (A2) present in the bottom mixture (S1) or optionally in the bottom phase (U2) is cleaved in the thermal splitting unit to give formic acid and tertiary amine (A1).
  • the carbon monoxide serving as a decomposition inhibitor can be added in gaseous form either into the feed or directly into the thermal splitting unit.
  • the formic acid is discharged from the thermal splitting unit.
  • the tertiary amine (A1) is recycled to the hydrogenation reactor in step (a).
  • the tertiary amine (A1) from the thermal cleavage unit can be recycled directly to the hydrogenation reactor. It is also possible to initially recycle the tertiary amine (A1) from the thermal splitting unit to the extraction unit in process stage (b2) or process stage (b3) and then to pass it on from the extraction unit to the hydrogenation reactor in step (a); this embodiment is preferred.
  • the thermal splitting unit comprises a second distillation apparatus and a third phase separation apparatus, wherein the cleavage of the formic acid-amine adduct (A2) is carried out in the second distillation apparatus to obtain a distillate (D2) discharged from the second distillation apparatus (taken ), and a biphasic bottoms mixture (S2) comprising an upper phase (03) containing the at least one tertiary amine (A1), and a lower phase (U3) containing the at least one formic acid-amine adduct (A2) and the at least contains an inhibitor.
  • D2 distillate
  • S2 biphasic bottoms mixture
  • the upper phase (03) contains the inhibited complex catalyst and the free ligands in addition to the tertiary amine (A1).
  • the removal of the formic acid from the second distillation apparatus obtained in the second distillation apparatus can be carried out, for example, (i) overhead, (ii) overhead and via a side draw, or (iii) only a side draw. If the formic acid is removed overhead, formic acid with a purity of up to 99.99% by weight. When taken off via a side draw, aqueous formic acid is obtained, in which case a mixture with about 85% by weight of formic acid is particularly preferred. Depending on the water content of the sludge mixture (S1) or, if appropriate, the lower phase (U2) fed to the thermal splitting unit, the formic acid can be withdrawn increasingly as top product or reinforced via the side draw.
  • S1 sludge mixture
  • U2 the lower phase fed to the thermal splitting unit
  • thermal cleavage of the formic acid-amine adduct (A2) is generally carried out according to the process parameters known in the prior art with respect to pressure, temperature and apparatus design. These are described, for example, in EP 0 181 078 or WO 2006/021 41 1.
  • distillation columns are suitable, which generally contain packing, packings and / or trays.
  • the bottom temperature in the second distillation apparatus is at least 130 ° C, preferably at least 140 ° C and more preferably at least 150 ° C, and generally at most 210 ° C, preferably at most 190 ° C, particularly preferably at most 185 ° C.
  • the pressure in the second distillation apparatus is generally at least 1 hPa abs, preferably at least 50 hPa abs and more preferably at least 100 hPa abs, and generally at most 500 hPa, more preferably at most 300 hPa abs and more preferably at most 200 hPa abs.
  • the bottoms mixture (S2) obtained in the bottom of the second distillation apparatus is biphasic.
  • the bottom mixture (S2) is fed to the third phase separation device of the thermal splitting unit and there in the upper phase (03) containing the tertiary amine (A1), the inhibited complex catalyst and the free ligands, and the lower phase (U3), which contains the formic acid-amine adduct (A2) and the inhibitor, separated.
  • the upper phase (03) is discharged from the third phase separator of the thermal splitting unit and recycled to the hydrogenation reactor in step (a).
  • the recycling can be carried out directly to the hydrogenation reactor in step (a) or the upper phase (03) is first supplied to the extraction unit in step (b2) or step (b3) and forwarded from there to the hydrogenation reactor in step (a).
  • the lower phase (U3) obtained in the third phase separation device is then supplied again to the second distillation device of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is then subjected to further cleavage in the second distillation apparatus, again giving formic acid and free tertiary amine (A1) and again in the bottom of the second distillation unit of the thermal splitting unit forms a two-phase bottoms mixture (S2), the then again the third phase separator of the thermal splitting unit is supplied for further processing.
  • the catalyst inhibited with carbon monoxide is enriched in the upper phase (03).
  • the inhibited complex catalyst contained in the upper phase (03) is converted back into the active form after the recirculation into the hydrogenation reactor under the conditions of the hydrogenation in step (a).
  • the inhibited catalyst prior to recycling in step (a), is subjected to a thermal treatment at temperatures in the range of 100 to 200 ° C in the absence of a carbon monoxide partial pressure.
  • absence of a carbon monoxide partial pressure is understood to mean that only the carbon monoxide which is bound to the inhibited complex catalyst or is split off from the inhibited complex catalyst during reactivation and replaced by free ligands is reactivated in the inhibited catalyst becomes.
  • the feeding of the bottom mixture (S1) or optionally of the bottom phase (U2) to the thermal splitting unit in process step (e) can take place in the second distillation device and / or the third phase separation device.
  • the feed of the bottom mixture (S1) or optionally the lower phase (U2) in the second distillation device of the thermal separation unit takes place.
  • the feed of the bottom mixture (S1) or optionally the lower phase (U2) takes place both in the second distillation device of the thermal splitting unit, as well as in the third phase separation device of the thermal splitting unit.
  • the bottoms mixture (S1) or optionally the lower phase (U2) is divided into two partial streams, wherein a partial stream of the second distillation apparatus and a partial stream of the third phase separator are fed to the thermal splitting unit.
  • FIG. 1 a block diagram of a preferred embodiment of the method according to the invention
  • FIG. 2 shows a block diagram of a further preferred embodiment of the method according to the invention
  • FIG. 3 shows a block diagram of a further preferred embodiment of the method according to the invention.
  • FIG. 4 shows a block diagram of a further preferred embodiment of the method according to the invention.
  • FIG. 5 shows a block diagram of a further preferred embodiment of the method according to the invention.
  • FIG. 6 shows a block diagram of a further preferred embodiment of the method according to the invention.
  • FIGS. 7, 8, 9 and 10 are graphical representations of the inhibition experiments H 1, H 2,
  • FIGS. 1 to 6 the reference symbols have the following meanings: FIG. 1
  • Amine adduct (A2) (lower phase (U2)); Swamp mixture (S1)
  • III-3 third phase separation device (the thermal splitting unit)
  • a stream 1 containing carbon dioxide and a stream 2 containing hydrogen are fed to a hydrogenation reactor 1-1. It is possible to supply the hydrogenation reactor 1-1 further streams (not shown) to compensate for any losses incurred by the tertiary amine (A1) or the complex catalyst.
  • the hydrogenation reactor 1-1 carbon dioxide and hydrogen are reacted in the presence of a tertiary amine (A1), a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the lower phase (U 1) is supplied as stream 3 to the distillation apparatus 11-1.
  • the upper phase (01) remains in the hydrogenation reactor 1-1.
  • the hydrogenation reactor 1-1 simultaneously acts as the first phase separation device.
  • the current 3 is added continuously or discontinuously, the inhibitor as stream 4.
  • the lower phase (U 1) is separated into a distillate (D 1) containing the polar solvent, which is recycled as stream 5 to the hydrogenation reactor 1-1, and into a biphasic bottom mixture (S1) containing an upper phase (02) containing the tertiary amine (A1) and the inhibited complex catalyst, and the lower phase (U2) containing the formic acid amine adduct (A2).
  • the sump mixture (S1) is supplied as stream 6 to the third phase separator 111-1 of the thermal splitting unit.
  • the sump mixture (S1) is separated, giving a tertiary phase (03) which is tertiary Amine (A1) and the inhibited complex catalyst, and a lower phase (U3) containing the formic acid-amine adduct (A2).
  • the upper phase (03) is recycled as stream 10 to the hydrogenation reactor 1-1.
  • the lower phase (U3) is supplied as stream 7 to the second distillation device IV-1 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-1 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a two-phase bottoms mixture (S2) are obtained.
  • the distillate (D2) containing formic acid is discharged as stream 9 from the distillation apparatus IV-1.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the lower phase (U3) containing the formic acid-amine adduct (A2) is added as stream 8 to the third phase separation device 111- 1 of the thermal splitting unit recycled.
  • the third phase separation device 111-1 the sump mixture (S2) is separated into upper phase (03) and lower phase (U3).
  • the upper phase (03) is recycled as stream 10 to the hydrogenation reactor 1-1.
  • the lower phase (U3) is recycled as stream 7 to the second distillation device IV-1.
  • a stream 11 containing carbon dioxide and a stream 12 containing hydrogen are fed to a hydrogenation reactor I-2. It is possible to supply the hydrogenation reactor I-2 further streams (not shown) in order to compensate for any losses of the tertiary amine (A1) or the complex catalyst.
  • a tertiary amine (A1) a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the hydrogenation mixture (H) is fed as stream 13a to a first phase separation device V-2.
  • the hydrogenation mixture (H) is separated into the upper phase (01) and the lower phase (U 1).
  • the upper phase (01) is recycled as stream 22 to the hydrogenation reactor I-2.
  • the lower phase (U 1) is supplied as stream 13b of the extraction unit VI-2.
  • the lower phase (U 1) is extracted with the tertiary amine (A1), which is the stream 20 (Upper phase (03)) is recycled from the third phase separation apparatus 111-2 to the extraction apparatus VI-2.
  • a raffinate (R2) and an extract (E2) are obtained.
  • the raffinate (R2) contains the formic acid-amine adduct (A2) and the polar solvent and is supplied as stream 13c to the first distillation apparatus I I-2.
  • the extract (E2) contains the tertiary amine (A1) and the residues of the complex catalyst and is recycled as stream 21 to the hydrogenation reactor I-2.
  • the current 13c is continuously or discontinuously added to the inhibitor as stream 14.
  • the raffinate (R 2) is separated into a distillate (D 1) containing the polar solvent, which is recycled as stream 15 to the hydrogenation reactor I-2, and into a biphasic sump mixture (S 1).
  • the bottoms mixture (S1) contains an upper phase (02) containing the tertiary amine (A1) and) the inhibited complex catalyst and a lower phase (U2) containing the formic acid-amine adduct (A2).
  • the bottoms mixture (S1) is fed as stream 16 to the second distillation device IV-2.
  • the formic acid-amine adduct present in the bottom mixture (S1) is cleaved in the second distillation device IV-2 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are obtained.
  • the distillate (D2) containing formic acid is discharged as stream 19 from the second distillation device IV-2.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and the lower phase (U3) containing the formic acid amine adduct (A2) is used as stream 18 third phase separation II I-2 of the thermal cleavage unit recycled.
  • the bottom mixture (S2) is separated to obtain a top phase (03) comprising the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U3) containing the formic acid-amine adduct (A2).
  • the upper phase (03) is recycled from the third phase separator II I-2 as stream 20 to the extraction unit VI-2.
  • the lower phase (U3) is supplied as stream 17 to the second distillation device IV-2 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-2 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottom mixture (S2) are again obtained.
  • a stream 31 containing carbon dioxide and a stream 32 containing hydrogen are fed to a hydrogenation reactor I-3. It is possible to supply the hydrogenation reactor I-3 with further streams (not shown) in order to compensate for any losses of the tertiary amine (A1) or of the complex catalyst which may occur.
  • carbon dioxide and hydrogen are reacted in the presence of a tertiary amine (A1), a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the hydrogenation mixture (H) is supplied as stream 33a to a first phase separation device V-3.
  • the hydrogenation mixture (H) in the upper phase (01) and the lower phase (U 1) is separated.
  • the upper phase (01) is recycled as stream 42 to the hydrogenation reactor I-3.
  • the lower phase (U 1) is supplied as stream 33b to the extraction unit VI-3.
  • the lower phase (U 1) is extracted with the tertiary amine (A1), which is recycled as stream 40 (upper phase (03)) from the third phase separator II I-3 of the thermal splitting unit to the extraction unit VI-3.
  • a raffinate (R2) and an extract (E2) are obtained.
  • the raffinate (R2) contains the formic acid-amine adduct (A2) and the polar solvent and is supplied as stream 33c to the first distillation device 11-3.
  • the extract (E2) contains the tertiary amine (A1) and the residues of the complex catalyst and is recycled as stream 41 to the hydrogenation reactor I-2.
  • the flow 33c is added continuously or discontinuously to the inhibitor as stream 34.
  • the raffinate (R2) is separated into a distillate (D1) containing the polar solvent, which is recycled as stream 35 to the hydrogenation reactor I-3, and into a biphasic bottoms mixture (S1).
  • the bottoms mixture (S1) contains an upper phase (02) containing the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U2) containing the formic acid-amine adduct (A2).
  • the sump mixture (S1) is supplied as stream 36 to the third phase separator II I-3 of the thermal splitting unit.
  • the bottom mixture (S1) is separated to obtain an upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst of a lower phase (U3) containing the formic acid-amine adduct ( A2).
  • the upper phase (03) is recycled as stream 40 to the extraction unit VI-3.
  • the lower phase (U3) is supplied as stream 37 to the second distillation device IV-3 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-3 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are obtained.
  • the distillate (D2) containing formic acid is discharged as stream 39 from the distillation device IV-3.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the lower phase (U3) containing the formic acid-amine adduct (A2) is added as stream 38 to the third phase separation II II -3 returned to the thermal splitting unit.
  • the bottom mixture (S2) is separated.
  • the upper phase (03) is recycled to the extraction unit VI-3.
  • the lower phase (U3) is recycled to the second distillation device IV-3.
  • a stream 51 containing carbon dioxide and a stream 52 containing hydrogen are fed to a hydrogenation reactor I-4. It is possible to supply the hydrogenation reactor I-4 further streams (not shown) to compensate for any losses of the tertiary amine (A1) or of the complex catalyst occurring.
  • a hydrogenation reactor I-4 carbon dioxide and hydrogen are reacted in the presence of a tertiary amine (A1), a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) is obtained which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the hydrogenation mixture (H) is fed as stream 53a to a first phase separation device V-4.
  • the hydrogenation mixture (H) is separated into the upper phase (01) and the lower phase (U 1).
  • the upper phase (01) is recycled as stream 62 to the hydrogenation reactor I-4.
  • the lower phase (U 1) is supplied as stream 53b to the extraction unit VI-4.
  • the lower phase (U 1) is extracted with the tertiary amine (A1), the current 60 (upper phase (03)) from the third phase separation II I-4 of the thermal splitting unit and the current 56c from the second phase separation VI I-4 to the extraction unit VI-4 is recycled.
  • a raffinate (R2) and an extract (E2) are obtained.
  • the raffinate (R2) contains the formic acid-amine adduct (A2) and the polar solvent and is supplied as stream 53c to the first distillation apparatus I I-4.
  • the extract (E2) contains the tertiary amine (A1) and the residues of the complex catalyst and is recycled as stream 61 to the hydrogenation reactor I-4.
  • the current 53c is added continuously or discontinuously to the inhibitor as stream 54.
  • the raffinate (R 2) is separated into a distillate (D 1) containing the polar solvent, which is recycled as stream 55 to the hydrogenation reactor 1-4, and into a biphasic bottom mixture (S1).
  • the bottoms mixture (S1) contains a top phase (02) containing the tertiary amine (A1) and the inhibited complex catalyst, and a bottom phase (U2) containing the formic acid-amine adduct (A2).
  • the bottoms mixture (S1) is fed as stream 56a to the second phase separation VI I-4.
  • the second phase separation device VII-4 the bottom mixture (S1) is separated into the upper phase (02) and the lower phase (U2).
  • the upper phase (02) is recycled from the second phase separator VI I-4 as stream 56c to the extraction unit VI-4.
  • the lower phase (U2) is supplied as stream 56b to the second distillation device IV-4.
  • the formic acid-amine adduct (A2) present in the lower phase (U2) is cleaved in the second distillation apparatus IV-4 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are obtained in the second distillation apparatus IV-4.
  • the distillate (D2) containing formic acid is discharged as stream 59 from the second distillation device IV-4.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and the lower phase (U3) containing the formic acid amine adduct (A2) is used as stream 58 third phase separation II I-4 recycled thermal splitting unit.
  • the bottom mixture (S2) is separated to obtain an upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U3) containing the formic acid-amine adduct (A2).
  • the upper phase (03) is recycled from the third phase separator II I-4 as stream 60 to the extraction unit VI-4.
  • the lower phase (U3) is supplied as stream 57 to the second distillation device IV-4 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-4 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are again obtained.
  • a stream 71 containing carbon dioxide and a stream 72 containing hydrogen are fed to a hydrogenation reactor I-5. It is possible to supply the hydrogenation reactor I-5 further streams (not shown) in order to compensate for any losses of the tertiary amine (A1) or of the complex catalyst.
  • a tertiary amine (A1) a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the hydrogenation mixture (H) is supplied as stream 73a to a first phase separation device V-5.
  • the hydrogenation mixture (H) in the upper phase (01) and the lower phase (U 1) is separated.
  • the upper phase (01) is recycled as stream 82 to the hydrogenation reactor I-5.
  • the lower phase (U 1) is supplied as stream 73b of the extraction unit VI-5.
  • the lower phase (U 1) is extracted with the tertiary amine (A1), which is recycled as stream 80 (upper phase (03)) from the third phase separator of the thermal splitting unit to the extraction unit VI-5.
  • a raffinate (R2) and an extract (E2) are obtained.
  • the raffinate (R2) contains the formic acid-amine adduct (A2) and the polar solvent and is supplied as stream 73c to the first distillation apparatus I I-5.
  • the extract (E2) contains the tertiary amine (A1) and the residues of the complex catalyst and is recycled as stream 81 to the hydrogenation reactor I-5.
  • the current 73c is added continuously or discontinuously to the inhibitor as stream 74.
  • the raffinate (R2) is separated into a water-rich distillate (D1 wr), a low-water distillate (D1wa) and a two-phase bottoms mixture (S1).
  • the water-rich distillate (D1 wr) is supplied as stream 83 to the stream 73a.
  • the low-water distillate (D1 wa) is recycled as stream 75 to the hydrogenation reactor I-5.
  • the embodiment according to FIG. 5 presupposes that the polar solvent used is a mixture of one or more alcohols with water.
  • the bottoms mixture (S1) contains an upper phase (02) containing the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U2) containing the formic acid-amine adduct (A2).
  • the sump mixture (S1) is fed as stream 76 to the third phase separator I I I-5 of the thermal splitting unit.
  • the bottom mixture (S1) is separated to obtain a top phase (03) comprising the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U3) containing the formic acid-amine adduct (A2).
  • the upper phase (03) is recycled as stream 80 to the extraction unit IV-5.
  • the lower phase (U3) is supplied as stream 77 to the second distillation device IV-5 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-5 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are obtained.
  • the distillate (D2) containing formic acid is discharged as stream 79 from the distillation apparatus IV-5.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and the lower phase (U3) containing the formic acid amine adduct (A2) is used as stream 78 third phase separation II I-5 recycled thermal splitting unit.
  • the sump mixture (S2) is separated in the third phase separation device I I I-5.
  • the upper phase (03) is recycled as stream 80 to the extraction unit VI-5.
  • the lower phase (U3) is recycled as stream 77 to the second distillation device IV-5.
  • a stream 91 containing carbon dioxide and a stream 92 containing hydrogen are fed to a hydrogenation reactor I-6. It is possible to supply the hydrogenation reactor I-6 with further streams (not shown) compensate for any losses of the tertiary amine (A1) or of the complex catalyst.
  • a hydrogenation reactor I-6 carbon dioxide and hydrogen are reacted in the presence of a tertiary amine (A1), a polar solvent and a complex catalyst containing at least one element from Groups 8, 9 and 10 of the Periodic Table.
  • a biphasic hydrogenation mixture (H) is obtained which has an upper phase (01) comprising the complex catalyst and the tertiary amine (A1) and a lower phase (U 1) containing the polar solvent, residues of the complex catalyst and the formic acid-amine adduct (A2 ) contains.
  • the hydrogenation mixture (H) is fed as stream 93a to the extraction unit VI-6.
  • the hydrogenation mixture (H) is extracted with the tertiary amine (A1), which is recycled as stream 100 (upper phase (03)) from the third phase separation device I II-6 of the thermal splitting unit to the extraction unit VI-6.
  • a raffinate (R1) and an extract (E1) are obtained.
  • the raffinate (R1) contains the formic acid-amine adduct (A2) and the polar solvent and is supplied as stream 93c to the first distillation apparatus I I-6.
  • the extract (E1) contains the tertiary amine (A1) and the complex catalyst and is recycled as stream 101 to the hydrogenation reactor I-6.
  • the current 93c is added continuously or discontinuously to the inhibitor as stream 94.
  • the raffinate (R1) is separated into a distillate (D1) containing the polar solvent, which is recycled as stream 95 to the hydrogenation reactor I-6, and into a biphasic mixture (S1).
  • the bottoms mixture (S1) contains a top phase (02) containing the tertiary amine (A1) and the inhibited complex catalyst, and a bottom phase (U2) containing the formic acid-amine adduct (A2).
  • the sump mixture (S1) is supplied as stream 96 to the third phase separator I I I-6 of the thermal splitting unit.
  • the bottom mixture (S1) is separated to obtain an upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and a lower phase (U3) containing the formic acid-amine adduct (A2).
  • the upper phase (03) is recycled as stream 100 to the extraction unit VI-6.
  • the lower phase (U3) is supplied as stream 97 to the second distillation device IV-6 of the thermal splitting unit.
  • the formic acid-amine adduct (A2) present in the lower phase (U3) is cleaved in the second distillation apparatus IV-6 into formic acid and free tertiary amine (A1).
  • a distillate (D2) and a bottoms mixture (S2) are obtained.
  • the distillate (D2) containing formic acid is discharged as stream 99 from the distillation device IV-6.
  • the biphasic bottoms mixture (S2) containing the upper phase (03) containing the tertiary amine (A1) and the inhibited complex catalyst and the lower phase (U3) containing the formic acid amine adduct (A2) is used as stream 98 third phase separation II I-6 of the thermal cleavage unit recycled.
  • the bottom mixture (S2) is separated in the third phase separation device II-6.
  • the upper phase (03) is recycled as stream 100 to the extraction unit VI-6.
  • the lower phase (U3) is recycled as stream 97 to the second distillation device IV-6.
  • Examples A-1 to A-6 show that in the process according to the invention even with variation of the tertiary amine (A1), the polar solvent, the complex catalyst with respect to the ligands and the metal component, the amount of catalyst, and the amount of water added high to very high reaction rates of up to 0.98 mol kg -1 r 1 can be achieved.
  • All investigated systems formed two phases, the upper phase (01) in each case with the still free tertiary amine (A1) and the complex catalyst, and the lower phase (U 1) in each case with the polar solvent and the formed formic acid-amine adduct ( A2) was enriched.
  • kR U (CR u upper phase (01) / c Ru lower phase (U 1)) indicates the distribution coefficient of the metal component of the complex catalyst in upper phase (01) and lower phase (U 1).
  • c Ru upper phase (01) is the concentration of the metal component of the complex catalyst in the upper phase (01)
  • c Ru lower phase (U 1) is the concentration of the metal component of the complex catalyst in the lower phase (U 1).]
  • Hastelloy C autoclave equipped with a paddle or magnetic stirrer was charged under inert conditions with the tertiary amine (A1), polar solvent and complex catalyst. Subsequently, the autoclave was sealed and C0 2 were pressed at room temperature. Subsequently, H 2 was pressed in and the reactor was heated with stirring (700-1000 rpm). After the specified reaction time, the autoclave was cooled and the hydrogenation mixture (H) was depressurized. After the reaction, water was optionally added to the reaction and stirred for 10 minutes at room temperature.
  • a biphasic hydrogenation mixture (H) was obtained in which the upper phase (01) with the tertiary amine (A1) and the complex catalyst, and the lower phase (U 1) with the polar solvent and the formic acid-amine adduct formed (A2 ) was enriched.
  • the phases were then separated and the formic acid content of the lower phase (U 1) was determined.
  • the total content of formic acid in the formic acid-amine adduct (A2) was determined by titration with 0.1 N KOH in MeOH, potentiometrically using a "Mettler Toledo DL50" titrator The parameters and results of the individual experiments are shown in Table 1 .2 and 1 .3.
  • Examples A-7 to A-12 show that under comparable conditions using methanol-water mixtures as the polar solvent higher formic acid concentrations in the lower phase (U 1) can be achieved compared to diols as the polar solvent.
  • Hastelloy C autoclave equipped with a magnetic stir bar was charged under inert conditions with tertiary amine (A1), polar solvent and complex catalyst. The autoclave was then closed and pressed at room temperature C0 2 . Subsequently, H 2 was pressed in and the reactor was heated with stirring (700 rpm). After the desired reaction time, the autoclave was cooled and the hydrogenation mixture (H) was depressurized.
  • a biphasic hydrogenation mixture (H) was obtained, the upper phase (01) containing the still free tertiary amine (A1) and the homogeneous catalyst, and the lower phase (U 1) containing the polar solvent and the formic acid amine formed.
  • Adduct (A2) was enriched.
  • the lower phase (U 1) was separated and under fresh conditions three times with the same amount (mass of tertiary amine corresponds to the mass of the lower phase) of fresh tertiary amine (10 minutes at room temperature stirring and then separate phases).
  • the total content of formic acid in the formic acid / amine adduct was determined potentiometrically by titration with 0.1 N KOH in MeOH using a "Mettler Toledo DL50" titrator
  • the ruthenium content was determined by AAS
  • the parameters and results of the individual experiments are in Table 1 .8 reproduced.
  • Examples D-1 to D-4 show that by varying the catalyst and the amount of water added during the formation of formic acid, the ruthenium in the product phase (raffinate R2) can be depleted to levels below one ppm ruthenium.
  • the lower phase (U 1) was separated and under inert conditions three times with the same amount (mass of amine corresponds to the mass of the lower phase) fresh tertiary amine (A1) (10 minutes at room temperature stirring and then separate phases) for catalyst extraction added.
  • the total content of formic acid in the formic acid-amine adduct (A2) was determined by titration with 0.1 N KOH in MeOH potentiometrically using a "Mettler Toledo DL50" titrator
  • the ruthenium content was determined by AAS The parameters and results of the individual Experiments are shown in Tables 1 .9 to 1 .10.
  • Examples E-1 to E-5 show that by varying the catalyst, the amount of water added (both before and after the reaction) and the reaction conditions, the active catalyst can be used again for C0 2 hydrogenation and the ruthenium in deplete the product phase down to 2 ppm with only one extraction.
  • Alcohol and water are distilled off from the product phase (containing the formic acid-amine adduct, corresponding to lower phase (U1), raffinate (R1) or raffinate (R2)) under reduced pressure using a rotary evaporator.
  • the product phase containing the formic acid-amine adduct, corresponding to lower phase (U1), raffinate (R1) or raffinate (R2)
  • a rotary evaporator In the bottom a biphasic mixture (trialkylamine and formic acid-amine adduct phase, corresponding to bottom mixture (S1)) is formed, the two phases are separated and the formic acid content of the lower phase (U2) becomes potentiometric by titration with 0.1 N KOH in MeOH determined with a "Mettler Toledo DL50" titrator
  • the amine and alcohol content is determined by gas chromatography
  • Table 1 The parameters and results of the individual experiments are shown in Table 1 .1.
  • Examples F-1 to F-4 show that in the process according to the invention, various polar solvents can be separated under mild conditions from the product phase (lower phase (U1), raffinate (R1) or raffinate (R2)), a lower phase containing lower U2 (U2 ) and an upper phase (02), consisting predominantly of tertiary amine, is obtained.
  • product phase lower phase (U1), raffinate (R1) or raffinate (R2)
  • U2 lower phase containing lower U2
  • an upper phase (02) consisting predominantly of tertiary amine
  • Examples G1 and G2 thermal separation of the polar solvent from the trialkylamine-solvent-formic acid mixtures and cleavage of the formic acid-amine adduct) alcohol and water are from the product phase (containing the formic acid-amine adduct, corresponding to lower phase (U 1), raffinate (R1) or raffinate (R2)) distilled off under reduced pressure by means of a rotary evaporator.
  • a biphasic mixture is formed in the bottom (trialkylamine and formic acid-amine adduct phase, bottom mixture (S1)) and the two phases are separated.
  • the composition of the distillate (containing most of the methanol and water; distillate (D1)), the upper phase (containing the free trialkylamine, upper phase (02)) and the lower phase (containing the formic acid-amine adduct; lower phase (U2)) was determined by gas chromatography and by titration of formic acid against 0.1 N KOH in MeOH potentiometrically using a "Mettler Toledo DL50" titrator.
  • the formic acid is then thermally cleaved from the lower phase (U2) from the first step in a vacuum distillation apparatus via a 10 cm Vigreux column from the tertiary amine (A2).
  • a single-phase bottom product (S2) is obtained, consisting of the pure tertiary amine (A2), which can be used for extraction of the catalyst and recycling into the hydrogenation.
  • the distillate (D2) contains formic acid and residual water.
  • composition of the sump (S2) and of the distillate was determined by gas chromatography and by titration of the formic acid with 0.1 N KOH in MeOH potentiometrically using a "Mettler Toledo DL50" titrator
  • the parameters and results of the individual experiments are shown in Table 1 .12 reproduced.
  • Examples G-1 and G-2 show that in the process according to the invention, various polar solvents can be separated from the product phase under mild conditions, with a lower (U3) formic acid and an upper phase (03) consisting predominantly of tertiary amine (A1).
  • U3 formic acid
  • U3 the formic acid-rich lower phase
  • the formic acid can then be cleaved off at higher temperatures from the tertiary amine (A1), the free tertiary amine (A1) being obtained.
  • the formic acid thus obtained still contains some water, which, however, can be separated from the formic acid by a column having a greater separation efficiency.
  • the resulting in both the separation of the solvent and in the thermal cleavage tertiary amine (A1) can be used to extract the catalyst.
  • the decomposition experiments for the solvent separation and the cleavage of the formic acid-amine adduct (A2) were carried out in 250 ml three-neck glass flasks with reflux condenser and argon cover.
  • the inhibition of the complex catalyst with CO was carried out during the experiment by means of a metal frit with the CO bubbled into the solution (5-6 I CO / h) was.
  • the reaction mixture was refluxed. Through a septum, the samples were taken by means of a syringe during the reaction for the determination of the phase ratio and the formic acid concentration.
  • the formic acid concentration was determined by titration against 0.1 N KOH in MeOH potentiometrically using a "Mettler Toledo DL50" titrator Synthesis of the catalyst stock solution (KS1) for inhibition experiments: 3.15 g of [Ru (COD) CI 2 ] in air are added to a 1 submitted .2 I Hastelloy autoclave, and 150 g trihexylamine (THA) was added. the autoclave is sealed, checked for leaks with N2 and purged with N 2.
  • KS1 catalyst stock solution
  • the phases are separated. This gives 501 g of an upper phase containing trihexylamine and the active catalyst (1900 ppm Ru) and 156 g of lower phase (680 ppm Ru) which is discarded.
  • the upper phase phase contains 83.5% of the ruthenium used and is subsequently used as catalyst stock solution (KS1) for the inhibition experiments.
  • Example H-1 shows that in the process according to the invention the decomposition of formic acid by residues of the complex catalyst under the conditions of thermal cleavage of the formic acid-amine adducts can be largely suppressed by addition of CO.
  • step (c) Inhibition in solvent removal: experiment H-2
  • Example H-2 shows that in the process according to the invention the decomposition of the formic acid by residues of the catalyst under the conditions of the solvent separation (step (c)) can be largely suppressed by addition of CO.
  • the amine phase which contains most of the inhibited complex catalyst, separated and used in the C0 2 hydrogenation.
  • 37.5 g of the amine phase from the experiment for inhibition 12.5 g of methanol and 1 g of water are placed in a 100 ml HC autoclave.
  • the autoclave is rendered inert with N 2 and 10 g of CO 2 (22 bar) are pressed on.
  • at 70 ° C pressed to 80 bar with H 2 and maintained the pressure over the reaction time by pressing with H 2 to 80 bar.
  • the concentration of formic acid in the product phase is 1.6% after 2 hours and 4.3% after 16 hours.
  • Example H-3 shows that in the process according to the invention the inhibited complex catalyst can be converted back into the active form under the hydrogenation conditions.
  • this reaction mixture is boiled under reflux for a further 10 hours without the addition of CO in order to reactivate the inhibited complex catalyst.
  • the formic acid is completely decomposed.
  • the amine phase which contains most of the complex catalyst, separated and used again in the C0 2 - hydrogenation.
  • 37.5 g of the amine phase from the experiment for inhibition 12.5 g of methanol and 1 g of water are placed in a 100 ml HC autoclave.
  • the autoclave is rendered inert with N 2 and 10 g of CO 2 (21 bar) are pressed on.
  • Example H-4 shows that in the process according to the invention, the inhibited complex catalyst can be converted back into the active form by thermal treatment without CO under the hydrogenation conditions, and then significantly faster in the hydrogenation and also that the complex catalyst even after inhibition and reactivation preferably present in the amine phase.

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Abstract

L'invention concerne un procédé de préparation d'acide formique, comportant les étapes: (a) réaction catalysée de façon homogène d'un mélange de réaction (Rg) contenant du dioxyde de carbone, de l'hydrogène, au moins un solvant polaire choisi dans le groupe composé de méthanol, d'éthanol, de 1-propanol, de 2-propanol, de 1-butanol, de 2-butanol, de 2-méthyl-1-propanol et d'eau et au moins une amine tertiaire représentée par la formule générale (A1) NR1R2R3, dans laquelle R1, R2, R3 représentent indépendamment les uns des autres un reste aliphatique, araliphatique ou aromatique, ramifié ou linéaire, acyclique ou cyclique, comprenant respectivement 1 à 16 atomes de carbone, des atomes de carbone individuels pouvant être substitués indépendamment les uns des autres par un hétérogroupe choisi dans les groupes -O- et >N-, deux restes ou les trois restes pouvant être reliés mutuellement de manière à former une chaîne comportant respectivement au moins quatre atomes, en présence d'au moins un catalyseur complexe contenant au moins un élément choisi dans les groupes 8, 9 et 10 du tableau périodique, dans un réacteur d'hydrogénation de manière à obtenir, éventuellement après addition d'eau, un mélange d'hydrogénation biphase (H) contenant une phase supérieure (O1) qui renferme le au moins un catalyseur complexe et la au moins une amine tertiaire (A1), et une phase inférieure (U1) qui renferme le au moins un solvant polaire, des restes du au moins un catalyseur complexe ainsi qu'au moins un produit d'addition d'acide formique-amine représenté par la formule générale (A2) NR1R2R3 * xi HCOOH, dans laquelle xi est compris entre 0,4 et 5 et R1, R2, R3 ont les significations indiquées plus haut; (b) traitement du mélange d'hydrogénation (H) obtenu à l'étape (a) selon une des étapes suivantes (b1) séparation de phase du mélange d'hydrogénation (H) obtenu à l'étape (a) dans un premier dispositif de séparation de phase, en la phase supérieure (O1) et la phase inférieure (U1), ou (b2) extraction du au moins un catalyseur complexe contenu dans le mélange d'hydrogénation (H) obtenu à l'étape (a) dans une unité d'extraction contenant un agent d'extraction qui renferme la au moins une amine tertiaire (A1) de manière à obtenir un raffinat (R1) contenant le au moins un produit d'addition d'acide formique-amine (A2) et le au moins un solvant polaire, et un extrait (E1) contenant la au moins une amine tertiaire (A1) et le au moins un catalyseur complexe, ou (b3) séparation de phase du mélange d'hydrogénation (H) obtenu à l'étape (a) dans un premier dispositif de séparation de phase, en la phase supérieure (O1) et la phase inférieure (U1), et extraction des restes du au moins un catalyseur complexe contenus dans la phase inférieure (U1) dans une unité d'extraction au moyen d'un agent d'extraction contenant la au moins une amine tertiaire (A1) de manière à obtenir un raffinat (R2) contenant le au moins un produit d'addition d'acide formique-amine (A2) et le au moins un solvant polaire, et un extrait (E2) contenant la au moins une amine tertiaire (A1) et les restes du au moins un catalyseur complexe; (c) séparation du au moins un solvant polaire issu de la phase inférieure (U1), du raffinat (R1) ou du raffinat (R2) dans un premier dispositif de distillation de manière à obtenir un distillat (D1) contenant le au moins un solvant polaire qui est ramené vers le réacteur d'hydrogénation à l'étape (a), et un mélange de résidus de distillation (S1) contenant une phase supérieure (O2) qui renferme la au moins une amine tertiaire (A1), et une phase inférieure (U2) qui renferme le au moins un produit d'addition d'acide formique-amine (A2); (d) éventuellement traitement du mélange de résidus de distillation (S1) obtenu à l'étape (c) par séparation de phase dans un second dispositif de séparation de phase, en la phase supérieure (O2) et la phase inférieure (U2); (e) fractionnement du au moins un produit d'addition d'acide formique-amine (A2) contenu dans le mélange de résidus de distillation (S1) ou dans la phase inférieure (U2), dans une unité de fractionnement thermique de manière à obtenir la au moins une amine tertiaire (A1) qui est ramenée vers le réacteur d'hydrogénation à l'étape (a), et de l'acide formique extrait de l'unité de fractionnement thermique, directement avant et/ou pendant l'étape (c), du dioxyde de carbone étant additionné à la phase inférieure (U1), au raffinat (R1) ou au raffinat (R2), et/ou directement avant et/ou pendant l'étape (e), du dioxyde de carbone étant additionné au mélange de résidus de distillation (S1) ou à la phase inférieure (U2).
PCT/EP2012/069458 2011-10-07 2012-10-02 Procédé de production d'acide formique par réaction de dioxyde de carbone avec de l'hydrogène WO2013050367A2 (fr)

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BR112014008338A BR112014008338A2 (pt) 2011-10-07 2012-10-02 processo para preparar ácido fórmico
CA2851175A CA2851175A1 (fr) 2011-10-07 2012-10-02 Procede de production d'acide formique par reaction de dioxyde de carbone avec de l'hydrogene
CN201280059095.3A CN103974927A (zh) 2011-10-07 2012-10-02 通过使二氧化碳与氢气反应制备甲酸的方法
RU2014118032/04A RU2014118032A (ru) 2011-10-07 2012-10-02 Способ получения муравьиной кислоты путем превращения диоксида углерода с водородом
IN3122DEN2014 IN2014DN03122A (fr) 2011-10-07 2012-10-02
SG11201400997TA SG11201400997TA (en) 2011-10-07 2012-10-02 Method for producing formic acid by reacting carbon dioxide with hydrogen
KR1020147011873A KR20140074373A (ko) 2011-10-07 2012-10-02 이산화탄소와 수소의 반응에 의한 포름산의 제조 방법
EP12766684.0A EP2763950A2 (fr) 2011-10-07 2012-10-02 Procédé de production d'acide formique par réaction de dioxyde de carbone avec de l'hydrogène

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US9499843B2 (en) 2011-07-15 2016-11-22 Verdant Bioproducts Limited Method of producing oil from a microorganism
US9994879B2 (en) 2011-07-15 2018-06-12 Verdant Bioproducts Limited Method of producing formic acid
US10480196B2 (en) 2012-04-04 2019-11-19 Valinge Innovation Ab Building panel with a mechanical locking system
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WO2016024293A1 (fr) 2014-08-12 2016-02-18 Council Of Scientific & Industrial Research Processus catalysé au métal pour la réduction de co2 en formate de sodium et en acide formique

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RU2014118032A (ru) 2015-11-20
JP2014530216A (ja) 2014-11-17
IN2014DN03122A (fr) 2015-05-22
KR20140074373A (ko) 2014-06-17
CN103974927A (zh) 2014-08-06
BR112014008338A2 (pt) 2017-04-18
CA2851175A1 (fr) 2013-04-11
SG11201400997TA (en) 2014-09-26
EP2763950A2 (fr) 2014-08-13

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