DE102005043142A1 - Deacidifying a fluid stream comprises absorbing acid gases in an absorbent comprising a polyamine and an aliphatic or alicyclic amine - Google Patents

Abstract

Deacidifying a fluid stream comprises absorbing acid gases in an absorbent comprising 0.3-60 wt.% of a polyamine (I) with at least two primary, secondary or tertiaryl amino groups and a molecular weight above 200, 0.1-70 wt.% or an aliphatic or alicyclic amine (II) with a molecular weight of 200 or less, and optionally 1-90 wt.% water. An independent claim is also included for an absorbent as above.

Description

The The present invention relates to a method for deacidifying a Fluid stream containing acid gases as an impurity. Farther For example, the invention relates to suitable absorbents therefor.

In numerous processes in the chemical or petrochemical industry occur fluid streams, the acid gases such as CO ₂ , H ₂ S, SO ₂ , CS ₂ , HCN, hydrogen halides, COS or mercaptans, especially aliphatic C ₁ - to C ₆ mercaptans as Contain impurities. These fluid streams may be, for example, gas streams such as natural gas, refinery gas or reaction gases resulting from the oxidation of organic materials such as organic wastes, coal, petroleum, natural gas or ethylene, or from the composting of organic substances containing wastes.

The Removal of the acid gases is due to different reasons special meaning. For example, the content of sulfur compounds of natural gas by appropriate treatment measures directly at the Natural gas source can be reduced, because the sulfur compounds make in that of natural gas often entrained Water acids, which have a corrosive effect. For Therefore, the transport of natural gas in a pipeline must have predetermined limits the sulphurous impurities are maintained. The at the oxidation of organic materials, such as organic waste Coal or petroleum, or in the composting of organic substances containing waste materials must arise reaction gases be removed to prevent the emission of gases that damage nature or can affect the climate, to prevent.

To the removal of acid gases used in gas scrubbing washings There is also an extensive patent literature.

Become frequent chemical solvents whose mode of action is based on chemical reactions, in which, after absorption, the dissolved acid gases substantially in the form of chemical compounds. For example at the industrial scale most frequently as chemical solvents used aqueous solutions from inorganic bases (e.g., potash solution in the Benfield process) or organic bases (e.g., organic amines) when dissolved in sour gas ions. The solvent can be by relaxing to a lower pressure and / or stripping be regenerated, with the ionic species reacting back to sour gases, evaporate and possibly be stripped by steam. After this Regeneration process can be the solvent be reused.

For the distance of carbon dioxide and hydrogen sulfide have become particular low molecular weight alkanolamines proven as washing solutions (see "Gas Purification", Arthur Kohl, Richard Nielsen, Gulf Publishing Company, Houston, Texas, 1997, 5th edition, Chapter 2, pages 40ff).

The US 4,096,085 describes an aqueous solution for the removal of acid gases from gas streams containing N-methyldiethanolamine or diethanolamine and as a corrosion inhibitor polymeric polyamines. The content of the polymeric polyamines is about 10 to 2000 ppm. Furthermore, such solutions are known from DE-A 2748216 and DE-A-2746913.

The US 5,281,254 relates to a method for removing water and carbon dioxide from gas streams, especially respiratory air, by means of a liquid absorbent. As Absorptionsmitels organic amines, including polyethyleneimines are proposed. To control the viscosity, it is recommended to dilute the absorbent by means of various organic solvents, for example alcohols, ethers or esters. The absorbent is separated from the gas stream requiring treatment by means of a membrane which is permeable to the gases to be removed.

The DE-A-2134379 relates to a process for the removal of gaseous sulfur compounds from gas streams, being as a washing solution alkoxylated Alkylenpolyamine used.

As already mentioned, gas purification usually comprises two steps: a) the absorption step, in which the gas requiring treatment is brought into contact with the absorbent, and b) the desorption step, in which the laden absorbent is stripped of the sour gas and thereby regenerated becomes. The regenerated absorbent may then be recycled to the absorption step. For the economics of such cleaning processes, it is important that the absorbent per Volume unit can absorb the largest possible amount of acid gas. Of particular importance in this context is the so-called acid gas stroke, ie the amount of sour gas which can be maximally absorbed by an absorbent under the conditions of the absorption step, minus the amount which remains in the absorbent after passing through the desorption step. Since during regeneration, depending on the absorbent and regeneration conditions, a different residual amount of sour gas remains in the absorbent, this value can sometimes be significantly different from the amount of gas that can be absorbed by an absorbent that is completely free of acid gases.

Farther of great Importance is the speed with which those contained in the fluid flow Sour gases are absorbed by the absorbent.

Regarding this both properties and their combination exists both at the working with low molecular weight amines method as well There is still room for improvement in the processes using high-molecular-weight amines.

In the case of low molecular weight primary and secondary amines, the corrosivity of the amine systems is also problematic compared to the steels commonly used in apparatus engineering, therefore, for example MEA only with 0.35 mol CO ₂ / mol amine, DEA only up to 0.40 mol CO ₂ / mol amine loaded, although both alkanolamines could be loaded higher.

• a) 0,3 bis 60 Gew.-% eines Polyamins mit mindestens 2 primären, sekundären oder tertiären Aminogruppen und einem Molekulargewicht von mehr als 200 g/mol (Polymeramin A),
• b) 0,1 bis 70 Gew.-% eines aliphatischen oder cycloaliphatischen Amins mit einem Molekulargewicht von 200 g/mol oder weniger (Monomeramin B)
• c) und ggf. 1 bis 90 Gew.-% Wasser

in Kontakt bringt, wobei ein mit dem Sauergas beladenes Absorptionsmittel und ein gereinigter Fluidstrom entsteht, und man den gereinigten Fluidstrom und das mit dem Sauergas beladene Absorptionsmittel voneinander separiert.Accordingly, there has been proposed a process for deacidifying a fluid stream containing acid gases as an impurity, comprising, in at least one absorption step, containing the fluid stream with an absorbent

• a) 0.3 to 60% by weight of a polyamine having at least 2 primary, secondary or tertiary amino groups and a molecular weight of more than 200 g / mol (polymer amine A),
• b) 0.1 to 70% by weight of an aliphatic or cycloaliphatic amine having a molecular weight of 200 g / mol or less (monomer amine B)
• c) and optionally 1 to 90 wt .-% water

bringing into contact, wherein a laden with the sour gas absorbent and a purified fluid stream is formed, and separating the purified fluid stream and the loaded with the sour gas absorbent from each other.

Farther the abovementioned absorbents were found.

The absorbent according to the invention or the process according to the invention is suitable for the removal of acid gases from fluid streams containing as acid gases CO ₂ , H ₂ S, COS, mercaptans, SO ₃ , SO ₂ , CS ₂ , hydrogen halides or HCN, in particular mixtures of the aforementioned acid gases ,

The content of CO ₂ in the fluid stream is generally 0.5-50 vol.%, Preferably 1-25 vol.%, Particularly preferably 2-15 vol.%.

The content of H ₂ S in the fluid stream is generally 0.05-25% by volume, preferably 0.1-15% by volume, particularly preferably 0.5-10% by volume.

The total content of H ₂ S and CO ₂ in the fluid stream is generally: 0.05-75% by volume, preferably 0.1-40% by volume, particularly preferably 0.5-25% by volume.

• – Erdgas
• – Syngas
• – LPG
• – Claus Tail Gas
• – Raffineriegas
• – einen Gasstrom, der bei der Oxidation organischer Substanzen gebildet wird
• – einen Gasstrom, der bei der Kompostierung und Lagerung organischer Substanzen enthaltender Abfallstoffe gebildet wird
• – einen Gasstrom, der bei der bakteriellen Zersetzung organische Substanzen gebildet wird.

The fluid streams are usually under normal conditions gaseous mixtures of compounds, for example to

• - natural gas
• - Syngas
• - LPG
• - Claus tail gas
• - Refinery gas
• - A gas stream, which is formed in the oxidation of organic substances
• - A gas stream, which is formed during the composting and storage of organic substances containing waste
• - A gas stream, which is formed in the bacterial decomposition organic substances.

Natural gas is a gas mixture which mainly comprises methane and optionally as minor components unsaturated and saturated C ₂ - to C ₄ -hydrocarbons and the acid gases as impurities.

The natural gas is freed and processed in different ways and to varying degrees depending on the later use of the sour gases. The purified natural gas is usually divided into the categories LNG (liquefied natural gas), sales gas, H ₂ S selective gas treatment gas.

If the natural gas is to be provided as LNG, the CO ₂ content is usually reduced to values of 100 ppm by volume or less, preferably 50 ppm by volume or less and the H ₂ S content to values of 4 ppm by volume or less and subsequently liquefying the purified gas.

If the natural gas is to be provided as a sales gas, the CO ₂ content is usually to values of 5 or 2 vol .-% or less, most commonly to values of 50 to 200 vol-ppm and the H ₂ S content to values lowered from 4 ppm by volume or less and then transported the purified gas, for example by pipeline to the consumer.

If the natural gas is to be provided as H ₂ S selective gas treatment gas, usually the CO ₂ content is not deliberately changed, but only the H ₂ S content is lowered to values of 4 ppm by volume or less , Since the removal of H ₂ S almost always a part of the possibly existing CO ₂ - mit is removed, the CO ₂ content is also here at 5 or 2 vol .-% or less.

at The syngas, also called synthesis gas, can be both so-called. Oxo-syngas as well to act on ammonia syngas.

The oxo-syngas is prepared from methane, naphtha, light fuel oil or heavy oil in the usual way by reaction with water vapor and air or oxygen (see Industrial Organic Chemistry, K. Weissermel, H.-J. Arpe, 5th ed. Wiley-VCH, 1998, chapter 2.1.1). It usually consists of CO and H ₂ as valuable products and CO ₂ as sour gas to be removed.

Ammonia synthesis gas is a mixture of H ₂ , CO ₂ and N ₂ . It is produced in the ammonia process during the steam splitting of methane. The resulting CO is converted with water vapor and air to CO ₂ and H ₂ . CO ₂ is separated off, for example, in activated methyldiethanolamine washes. Ideally, N ₂ and H _{2 are left over} for ammonia synthesis.

LPG is an abbreviation for Liquefied Petroleum Gas. LPG is a mixture mainly of the hydrocarbons propane, butane, isobutane, propene and butenes. They are gaseous at normal pressure and temperature, but can be liquefied by cooling and / or compression. LPG is gained in the so-called stabilization of crude oil. This crude oil is degassed, so build up during storage in tanks no high pressures. LPG, along with NGL (= natural gas liquids, which are mainly ethane and some propane), is also involved in the fractionation of crude oil and is withdrawn in columns overhead. LPG contains as sour gases mainly H ₂ S, CO ₂ and mercaptans.

The Claus Tail Gas is a gas stream produced by the Claus process. In the Claus process, H ₂ S is catalytically converted to elemental sulfur via SO ₂ . In turn, the H ₂ S- and SO ₂ -containing tail gas leaving the Claus process has to be worked up. One method works in such a way that all sulfur components of the tail gas are catalytically converted back to H ₂ S. With the process according to the invention, the H ₂ S can be removed from the Claus Tail gas and the Claus tail gas treated in this way can be returned to the Claus process. The Claus process and Claus tail gas are well known to those skilled in the art and described in Ullmann's Encyclopedia of Industrial Chemistry, Sixth edition, 2000 electronic release, Wiley-VCH.

Refinery gas usually consists of low molecular weight hydrocarbons such as C ₁ to C ₅ hydrocarbons and often contains H ₂ S as an impurity.

With regard to the origin and composition of refinery gas, the following can be said: Crude oil contains a more or less large proportion of organically bound sulfur, depending on the eligible area and quality. This sulfur is released in various purification stages (hydrodesulfurization) or methods for increasing the gasoline yield (catalytic cracker, hydrocracker, hydrotreater, etc.) in the form of H ₂ S and is found in the gas streams from also formed light hydrocarbons. This mixture is commonly referred to as refinery gas.

What the gas stream formed during the oxidation of organic substances is concerned, so you can between flue gases (flue gas) and reaction gases from oxidation-based manufacturing processes.

When Organic substances which are subjected to oxidation usually become fossil fuels such as coal, natural gas or petroleum or organic substances containing waste materials used.

The Oxidation of the organic substances usually takes place in the usual way Incinerators with air.

For example, in oxidation-based manufacturing processes, ethylene together with oxygen may be catalytically converted to ethylene oxide. For this purpose, reaction gas is circulated. Ethylene and oxygen are continuously fed to the reaction gas. Ethylene oxide is formed in a reactor. Ethylene oxide is separated from the reaction gas after the reaction. The major secondary reaction and main sequence reaction is the total oxidation of ethylene or ethylene oxide to CO ₂ . This must also be removed continuously from the cycle gas, since it is leveling up.

After the gas phase reaction in the reactor, ethylene oxide in a column is separated (absorbed) by water scrubbing. Then a part or all of the remaining cycle gas, which may still contain oxygen and traces of ethylene oxide, freed of CO ₂ in a further wash column, enriched again with ethylene and oxygen and in turn driven into the reactor. The purification of the circulating gas of CO ₂ does not have to be complete. In the context of optimization considerations, only partial CO ₂ enrichment can be the economically more favorable solution for the overall process.

What the gas stream used in the composting or storage of organic Substances containing waste substances is formed, such are the waste substances containing organic substances mostly with household waste, Plastic waste or packaging waste.

The Composting and storage of organic substances containing waste materials generally takes place in landfills.

What the gas stream, the organic substances in the bacterial decomposition stables, straw, Slurry, sewage sludge, Fermentation residues used.

The bacterial decomposition occurs e.g. in usual biogas plants.

suitable Polymeramines A include, in particular, polyvinylamines, polyvinylamidoamines, Polyethyleneimines, polypropyleneimines, polyamidoamines or polyureas.

They preferably have a weight-average molecular weight (M _w ) of from 200 to 3,000,000, preferably from 200 to 2,000,000 g per mole. In general, the content of amino groups is 5 to 35 mol per kg, preferably 5 to 25 mol per kg, more preferably 10 to 24 mol per kg.

The Structure of the polymers can be chosen so that it linear, branched or hyperbranched polymers, star polymers or dendrimers.

at The polyethyleneimines and polypropyleneimines are particularly linear, branched or hyperbranched polymers are preferred. These include in particular Homopolymers containing 4, 5, 6, 10, 20, 35 and 100 repeating units.

mit einer mittleren Molmasse (M_w) von 200 bis 2.000.000, in der die Reste R¹ bis R⁶ unabhängig voneinander Wasserstoff, lineare oder verzweigte C₁- bis C₂₀-Alkyl-, -Alkoxy-, -Polyoxyethylen-, -Hydroxyalkyl-, -(Alkyl)carboxy-, -Phosphonoalkyl-, -Alkylaminoreste, C₂- bis C₂₀-Alkenylreste oder C₆- bis C₂₀-Aryl-, -Aryloxy-, -Hydroxyaryl-, -Arylcarboxy-, oder -Arylaminoreste, die gegebenenfalls weiter substituiert sind, und R⁴ und R⁵ darüber hinaus noch weitere Polyethylenimin-Polymerketten bedeuten und x, y und z unabhängig voneinander jeweils 0 oder eine ganze Zahl bezeichnen. R¹ kann darüber hinaus auch eine primäre Aminogruppe bedeuten.Preferred polyethyleneimines are those of the general formula (I)

having an average molecular weight (M _w ) of 200 to 2,000,000, in which the radicals R ¹ to R ^{6 are} independently Hydrogen, linear or branched C ₁ to C ₂₀ alkyl, alkoxy, polyoxyethylene, hydroxyalkyl, (alkyl) carboxy, phosphonoalkyl, alkylamino, C ₂ to C ₂₀ alkenyl radicals or C ₆ - to C ₂₀ -aryl, -aryloxy, -hydroxyaryl, -arylcarboxy- or -Arylaminoreste, which are optionally further substituted, and R ⁴ and R ⁵ further denote further polyethyleneimine polymer chains and x, y and each of z independently denotes 0 or an integer. In addition, R ¹ may also be a primary amino group.

The sum of x, y and z should be chosen so that the average molecular weight is in the specified range. Preferred ranges for the average molecular weight (M _w ) of the polyethyleneimines of the general formula I are from 250 to 500,000, in particular from 300 to 100,000.

Preferred radicals R ¹ to R ⁶ are hydrogen, methyl, ethyl, carboxymethyl, carboxyethyl, phosphonomethyl, 2-hydroxyethyl, 2- (2'-hydroxyethoxy) ethyl and 2- [2 '- (2 "-hydroxyethoxy) -ethoxy] ethyl and for R ^{1 is} a primary amino group.

Commercially available polyethyleneimines are sold under the trade names Lupasol ^® from BASF Aktiengesellschaft, for example. For linear and branched polyethylene imines, see also Römpp, Chemisches Lexikon, online version 2004, Georg Thieme-Verlag and further literature cited therein.

Particularly preferred polyvinylamines and polyvinylamidoamines are linear polyvinylamines. Polyvinylamines are well known and described for example in EP-A-71050. Commercially available linear polyvinylamines are sold under the trade names Lupamin ^® or Catiofast® ^® from BASF Aktiengesellschaft, for example.

preferred Polyvinylamines and polyvinylamidoamines are polyallylamine, poly (diallyldimethylammonium chloride), Polyvinylformamide, polyvinylpyrrolidone, polyvinylacetamide, polyvinylmethylformamide, Polyvinylmethylacetamide, poly (dimethylaminopropylmethacrylamide), Poly (dimethylaminoethyl acrylate), poly (diethylaminoethyl acrylate), Poly (acryloylethyltrimethylammonium chloride), poly (acrylamidopropyltrimethylammonium chloride), Poly (methacrylamidopropyltrimethylammonium chloride), polyacrylamide, Poly (vinyl pyridine) Hexadimethrine bromide, poly (dimethylamine-co-epichlorohydrin), poly (dimethylamine-co-epichlorohydrin-co-ethylenediamine), Poly (amidoamine-epichlorohydrin) or copolymers containing N-vinylformamide, Allylamine, diallyldimethylammonium chloride, N-vinylacetamide, N-vinylpyrrolidone, N-methyl-N-vinylformamide, N-methyl-N-vinylacetamide, dimethylaminopropylmethacrylamide, Dimethylaminoethyl acrylate, diethylaminoethyl acrylate, acryloylethyltrimethylammonium chloride or methacrylamidopropyltrimethylammonium chloride in copolymerized Form and optionally in split form. Farther can the said polymers in cationic or else anionic form, and their salts are used. Preference is given to nonionic or cationic polyvinylformamides, polyvinylamine, polyacrylamide and poly (diallyldimethylammonium chloride). Particularly preferred cationic polyvinylformamide or polyvinylamine.

mit einer mittleren Molmasse (M_w) von 200 bis 2.000.000, in der die Reste R⁷ bis R¹¹ unabhängig voneinander Wasserstoff, lineare oder verzweigte C₁- bis C₂₀-Alkyl-, -Alkoxy-, -Polyoxyethylen-, -Hydroxyalkyl-, -(Alkyl)carboxy-, -Phosphonoalkyl-, -Alkylaminoreste, C₂- bis C₂₀-Alkenylreste oder C₆- bis C₂₀-Aryl-, -Aryloxy-, -Hydroxyaryl-, -Arylcarboxy-, oder -Arylaminoreste, die gegebenenfalls weiter substituiert sind, und darüber hinaus noch einen Formamidyl-, Pyrrolidonyl- oder Imidazolylrest bedeuten, s eine ganze Zahl bezeichnet und t für 0 oder eine ganze Zahl steht, wobei das genannte Polyvinylamin auch an in den Verbindungen (II) vorhandenen tertiären und/oder noch vorhandenen freien primären und/oder sekundären N-Atomen quatemiert sein kann.Particularly preferred is a polyvinylamine of the general formula (II)

having an average molar mass (M _w ) of 200 to 2,000,000, in which the radicals R ⁷ to R ¹¹ independently of one another are hydrogen, linear or branched C ₁ -C ₂₀ -alkyl, -alkoxy, -polyoxyethylene, Hydroxyalkyl, - (alkyl) carboxy, -phosphonoalkyl, -alkylamino, C ₂ - to C ₂₀ -alkenyl or C ₆ - to C ₂₀ -aryl, -aryloxy, -hydroxyaryl, -arylcarboxy-, or - Arylamino radicals, which are optionally further substituted, and furthermore a formamidyl, pyrrolidonyl or imidazolyl radical, s is an integer and t is 0 or an integer, said polyvinylamine also being present in the compounds (II) tertiary and / or remaining free primary and / or secondary N atoms can be quaternized.

The sum of s and t should be chosen so that the average molecular weight is in the specified range. Preferred ranges for the average molecular weight (M _w ) of the polyvinylamines (V) are 500 to 500,000, in particular 800 to 50,000.

Preferred meanings for the radicals R ⁷ to R ¹¹ are also those given above for R ¹ to R ⁶ in the general formula I.

As further polymers find linear polyamidoamines as well as branched or hyperbranched polyamidoamines, as described for example in US 4435548 . EP 115 771 . EP 234 408 . EP 802 215 , in LJ Hobson and WJ Feast, Polymer 40 (1999), 1279-1297 or in H.-B. Mekelburger, W. Jaworek and F. Vögtle, Angew. Chemistry 1992, 104, no. 12, 1609-1614, use.

Preferred polyamidoamines preferably have an average molecular weight (M _w ) of 500 to 1,000,000. They are obtainable, for example, by reacting C ₁₀ -C ₁₀ -dicarboxylic acids or tricarboxylic acids with poly (C ₂ -C ₄ -alkylene) polyamines having 2 to 20 basic nitrogen atoms in the molecule, which are an appropriate number of primary and / or secondary amino groups which are capable of forming amide or ester bonds with the carboxylic acid.

Particularly preferred ranges for the average molecular weight (M _w ) of the polyamidoamines are 800 to 800,000, in particular 1000 to 500,000.

As a further class of polymers amino groups containing polyurea find use. Preference is given to branched or hyperbranched amino-containing polyureas, for example as described in the EP 1 474 461 , DE-A 10351401.5 and DE-A 102004006304.4 and in EP 1 273 633 , US 2002/0161113 or US 2003/0069370.

dendrimers or dendrimer-type amines or their precursors are, for example N, N, N ', N'-Tetraaminopropylalkylendiamin, wherein as the alkylene unit is preferably the ethylene or butylene unit chosen is, these amines usually designated as N6-amines, measured by the number of nitrogen atoms as well as the dendrimers obtainable therefrom by aminopropylation Amines such as N14, N30, N62 and N128 amine. These amines have a Ethylenediamine or Butylenediamine backbone whose hydrogen atoms are substituted on the nitrogen by amino (n-propyl) radicals. The thereby terminal Amino groups can in turn be substituted by corresponding aminopropyl groups (N14-amine), etc. Manufacturing processes for these amines are described in WO 96/15097, starting from ethylenediamine. Also preferred Examples of these amines are corresponding N-amines, as described in WO 93/14147, starting from butylenediamine instead as above, ethylene diamine are produced.

Other dendrimers or dendrimer-type amines can be constructed, for example, based on polyamide chemistry, as described, for example, in US Pat US 4568737 or US 5338532 ,

A Another class of nitrogen-containing polymers are Amino-containing star polymers as described, for example in WO 96/35739.

When Monomer amine B can be considered in various groups of compounds, especially aliphatic or cycloaliphatic amines having 2 to 12 Carbon atoms, alkanolamines of 2 to 12 carbon atoms, cyclic amines in which 1 or 2 nitrogen atoms together with 1 or 2 alkanediyl groups form 5-, 6- or 7-membered rings.

When Monomer amine B are preferably the groups listed below B1 to B9 into consideration.

primary alkanolamines (monomeramines B1)

Monoethanolamine, 2- (2-aminoethoxy) ethanol, 3-amino-1-propanol, 2-amino-2-methyl-1-propanol, 3-amino-3-methyl-2-pentanol, 2-amino-2-methyl-3-pentanol 2-amino-2-methyl-1-butanol, 3-amino-3-methyl-1-butanol, 3-amino-3-methyl-2-butanol, 2-amino-2,3-dimethyl-3-butanol, 2-amino-2,3-dimethyl-1-butanol, 2-amino-2-methyl-1-pentanol

secondary alkanolamines (monomeramines B2)

diisopropanolamine, Diethanolamine, hydroxypiperazine, N, N'-bis (2-hydroxyethyl) piperazine, 2-piperazinoethanol, 4-hydroxy, 2,2,6,6-tetramethylpiperidine, 2-methylaminoethanol, 2-ethylamino-ethanol, 2-propylamino-ethanol, 2-isopropylaminoethanol, 2-n-butylaminoethanol, 2-methylpiperazine, 2,5-dimethylpiperazine, 2-piperidinoethanol, 2-sec-butylaminoethanol, 2-i-butylaminoethanol, 2-t-butylaminoethanol, 1-ethylamino-ethanol, 1-methylamino-ethanol, 1-propylamino-ethanol, 1-isopropylamino-ethanol.

tertiary alkanolamines (monomeramines B3)

Triethanolamine, N-methyldiethanolamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, tetramethyl-1,3-propanediamine, N-piperidineethanol, tertiary aliphatic alkanolamine having 2-12 C atoms, 2- (Di methylamino) ethanol, 2- (diethylamino) ethanol, 2- (ethylmethylamino) ethanol, 1- (dimethylamino) ethanol, 1- (diethylamino) ethanol, 1- (ethylmethylamino) ethanol, 3-dimethylamino-1 propanol, 4-dimethylamino-1-butanol, 2-dimethylamino-2-methyl-1-propanol; N-ethyl-N-methylethanolamine, N-ethyldiethanolamine, Nt-butyldiethanolamine, N-alkyldiisopropanolamine, alkyl = C ₁ - to C ₄ -alkyl, 2- (2- (dimethylamino) ethoxy) -ethanol = half-Niax, N - (2- (dimethylaminoethyl) -methylamino) -ethanol = semi-PMDETA, N-butyldiethanolamine, N-tertiary-butyldiethanolamine, 2-morpholinoethanol.

prim. Amines (Monomeramines B4)

3-methylaminopropylamine, 4-methylaminobutylamine, diaminotoluenes (DAT) = 2,3-DAT, 2,4-DAT, 2,5-DAT, 2,6-DAT, 3,4-DAT, 3,5-DAT, 2,2-dimethyl-1,3-diaminopropane, hexamethylenediamine = HMD.

sec. Amines (Monomeramines B5)

3-methylaminopropylamine, 4-methylaminobutylamine, piperazine, piperidine, 2,2,6,6-tetramethylpiperidine, homopiperazine, 2-methylpiperazine, alkylpiperazines, 2,5-di (C ₁ to C ₅ alkyl) piperazine, N- (2-aminoethyl) piperazine, N-ethyl piperazine, N- (2-aminoethyl) piperazine, morpholine,

Amines of the general formula III R ^a -NH-R ^b -NH ₂ III in which R ^a = C ₁ - to C ₆ -alkyl, and R ² = C ₂ - to C ₆ -alkylene, preferably C ₂ - to C ₃ -alkylene,

Amines of the general formula IV R ^c -NH-R ^d -NHR ^d IV in which R ^c = methyl, R ^d = alkylene having 2-3 C atoms, R ^e = methyl or hydrogen.

tert. Amines (Monomeramines B6)

1-alkyl-piperidines, Alkyl = C1-C6, 2,5-dimethylpiperazine, bis (2-dimethylaminoethyl) ether = Niax, N, N, N ', N'-tetramethyl-1,3-propanediamine = TMPDA, N, N, N ', N'-tetramethyl-1,4-butanediamine = TMBDA, 4-ethylmorpholine, 1,8-diazabicyclo [5.4.0] undec-7-ene, pyrazine

sterically hindered primary and secondary amines (Monomeramine B7)

2-substituted Piperidine, with an alkyl group substituted with a hydroxyl group is; 2-amino-2-methyl-1-propanol (= AMP), 2- (methylamino) ethanol, 2- (ethylamino) ethanol, 2- (diethylamino) ethanol, 2- (2-hydroxyethyl) piperidine; t-butyl-aminoethoxyethanol (TBAEE) = t-butyldiglycolamine, mixtures from 100 parts by weight: 2-amino-2-methyl-1-propanol, 2-amino-2-ethyl-1,3-propanediol, 2-amino-2-hydroxymethyl-1,3-propanediol and 1 to 25 parts by weight: piperazine, piperidine, morpholine, glycine, 2-methyl-aminoethanol, 2-piperidineethanol, 2-ethylaminoethanol, 1- (ethylamino) -ethanol, 1- (methylamino) ethanol, 1- (propylamino) ethanol, 1- (isopropylamino) ethanol

prim. u. sec. Diamine (Monomeramine B8)

ethyleneamines such as dieethylenetriamine, triethylenetetramine, tetraethylenepentamine, and 3-methylaminopropylamine, 4-methylaminobutylamine and half-PMDETA = N- (2-hydroxyethyl) -N, N, N'-trimethylethylenediamine

prim. u. sec. triamine (Monomeramine B9)

• PMDETA = N, N, N ', N ", N" -pentamethylenediethylenetriamine,

For the individual Areas of application are in particular the following blends.

Blend 1

Mixtures of a polymer amine A and monomeramines B, selected from the groups of Mo nomeramine B3 and (B4 or B5 or B8).

composition (below always for the ready-to-use absorption solution):

Polymeramine A:

• 0.3-80 Wt .-%, preferably 2-50 wt .-%, particularly preferably 10-40 wt .-%, most preferably 12-25 Wt .-%

B3:

• 1-50% by weight, preferably 5-40% by weight, more preferably 10-30 % By weight, most preferably 12-25% by weight

B4 or B5 or B8:

• 1-35 wt .-%, preferably 1.5-25 wt .-%, particularly preferably 2.5-15 Wt .-%

Blend 2

mixtures from a polymer amine A and a monomer amine B selected from the group of monomeramins B1.

Polymeramine A:

• 0.3-60 Wt .-%, preferably 1-40 Wt .-%, particularly preferably 5-25 Wt .-%

B1:

• 1-70 Wt .-%, preferably 2-50 Wt .-%, more preferably 5-40 Wt .-%.

If the monomer amine B1 is 2- (2-aminoethoxy) ethanol (AEE) is the most preferred concentration range 40 to 65% by weight. If the monomer amine B1 is MEA, so the most preferred concentration range is 20 to 60 Wt .-%.

Blend 3

mixtures from a polymer amine A and a monomer amine B selected from the group of monomeramine B2.

Polymer amine:

• 0.3-50 Wt .-%, preferably 1-35 Wt .-%, more preferably 5-20 Wt .-%

B2:

• 1-70 Wt .-%, preferably 10-50 Wt .-%, more preferably 15-40 Wt .-%

Blend 4

mixtures from a polymer amine A and a monomer amine B selected from the group of monomeramine B5 or B8.

Polymeramine A:

• 0.3-60 Wt .-%, preferably 5-40 Wt .-%, particularly preferably 10-30 Wt .-%

B5 or B8:

• 1-60 wt .-%, preferably 2-40 wt .-%, particularly preferably 5-35 wt .-%, most preferably 8-25 Wt .-%

Blend 5

mixtures from a polymer amine A and a monomer amine B selected from the group of monomeramine B3.

Polymer amine:

• 0.3-60 Wt .-%, preferably 1-40 Wt .-%, more preferably 5-35 Wt .-%, most preferably 10-25 wt .-%,

B3:

• 1-60 Wt .-%, preferably 5-50 Wt .-%, more preferably 10-40 % By weight, most preferably 15-30% by weight

Blend 6

mixtures from a polymer amine A and a monomer amine B selected from the group of monomeramine B7.

Polymer amine:

• 0.3-60 Wt .-%, preferably 2-40 Wt .-%, more preferably 5-35 % By weight, most preferably 15-25% by weight

B7:

• 1-65 Wt .-%, preferably 5 - 40 Wt .-%, particularly preferably 10-30 % By weight, most preferably 15-25% by weight

Blend 7

Mixtures of a polymer amine A, a monomer amine B, selected from the groups of monomeramine B7 and a monomer amine B, selected from the group of monomeramines B1, B2, B4, B5 and B8. The monomeramines B1, B2, B4, B5 or B8 serve as activators for adjusting the selectivity of the solvent. Therefore, there is no universally valid ideal range for your concentration. Depending on the desired proportion of not absorbed in the gas scrubbing CO ₂ , the proportion may vary.

Polymer amine:

• 0.3-60 Wt .-%, preferably 2-40 Wt .-%, particularly preferably 5 - 30 % By weight, most preferably 12-25% by weight

B7:

• 1-65 Wt .-%, preferably 5-40 Wt .-%, particularly preferably 10 - 30 % By weight, most preferably 15-25% by weight

B1 or B2 or B4 or B5 or B8:

• 0.3-20 Wt .-%, preferably 0.5 - 10 Wt .-%, more preferably 1-7 Wt .-%

Of the Water content of the absorbent is 1-90 wt .-%, preferably 20-75 wt .-%, very particularly preferably 35-70 Wt .-%.

In the following Table I is marked by "X", which blends are preferably used for which applications

The Inventive absorbents is for the removal of acidic gases (hereinafter also referred to as acidic Gas components) from gases coming from the absorbent itself can not be absorbed to a significant extent and for extraction acid gases from liquids, which are substantially immiscible with the absorbent, suitable. The basic procedure for a gas scrubber as well as possible Variants within the scope of the present invention are described. The method can easily be transferred to liquids by a person skilled in the art. The regeneration of the absorbent is identical for liquids and gases.

The on sour gas components rich starting gas (raw gas) is in a Absorption step in an absorber in contact with the absorbent according to the invention brought, whereby the acid gas components at least partially be washed out.

When Absorber preferably acts in conventional gas scrubbing used washing device. Suitable washing devices are for example, centrifugal absorbers, packing, packing and tray columns, Membrane contactors, radial flow scrubbers, Jet scrubbers, Venturi scrubbers and rotary spray washer, preferred Packing, packing and Tray columns, more preferably packed and packed columns. The treatment of the fluid flow with the absorbent takes place preferably in a column in countercurrent. The fluid is here generally in the lower area and the absorbent fed to the top of the column.

The Temperature of the absorbent is in the absorption step in Generally about 40 to 100 ° C, when using a column, for example 40 to 70 ° C at the top the column and 50 to 100 ° C. at the bottom of the column. The total pressure is in the absorption step in Generally about 0.95 to 120 bar, preferably about 1.05 to 100 bar. It becomes a lean acid gas constituent, i. one at this Components depleted product gas (clean gas) and one with acidic Gas components loaded absorbent received.

The inventive method may be one or more, in particular two, successive absorption steps include. The absorption can be done in several successive steps carried out be, wherein the raw gas containing the acidic gas components in each of the substeps, each with a partial flow of the absorbent is brought into contact. The absorbent with which the raw gas in Contact is already partially loaded with acidic gases be, i. it may be, for example, an absorbent, from a subsequent absorption step in the first absorption step was returned, or act to partially regenerated absorbent. Regarding the Carrying out the Two-stage absorption is referred to the publications EP-A 0 159 495, EP-A 0 20 190 434, EP-A 0 359 991 and WO 00100271.

According to a preferred embodiment, the method according to the invention is carried out such that the fluid containing the acidic gases is first absorbed by the absorption in a first absorption step is treated at a temperature of 40 to 100 ° C, preferably 45 to 90 ° C and in particular 50 to 90 ° C. The depleted in sour gases fluid is then treated in a second absorption step with the absorbent at a temperature of 30 to 90 ° C, preferably 35 to 80 ° C and especially 40 to 80 ° C. The temperature is 5 to 20 ° C lower than in the first absorption stage.

Out the absorbent laden with the acid gas components can the acid gas components in usual Manner (analogous to the publications cited below) in one Regeneration step to be released, with a regenerated Absorbent is obtained. In the regeneration step, the loading becomes of the absorbent is reduced and the resulting regenerated Absorbent is preferably subsequently in the absorption step recycled.

In general, the regeneration step involves at least depressurizing the loaded absorbent from a high pressure prevailing in the absorption step to a lower pressure. An exception is Flue gas scrubbing, where absorption is generally operated at about ambient pressure, while regeneration is due to elevated temperatures at elevated pressures. The pressure release can be done in example by means of a throttle valve and / or a relaxation turbine. The regeneration with a relaxation stage is described for example in the publications US 4,537,753 and US 4,553,984 ,

The release of the acidic gas constituents in the regeneration step can be carried out, for example, in a flash column, for example a vertically or horizontally installed flash tank or a countercurrent column with internals. Several expansion columns can be connected in series, in which regeneration takes place at different pressures. For example, in a pre-relaxation column at high pressure, which is typically about 1.5 bar above the partial pressure of the acid gas components in the absorption step, and in a main expansion column at low pressure, for example 1 to 2 bar absolute, regenerated. Regeneration with two or 30 more flash stages is described in the references US 4,537,753 . US 4,553,984 , EP-A 0 159 495, EP-A 0 202 600, EP-A 0 190 434 and EP-A 0 121 109.

A process variant with two low-pressure expansion stages (1 to 2 bar absolute), in which the absorption liquid partially regenerated in the first low-pressure expansion stage is heated, and in which a medium-pressure expansion stage is provided, optionally before the first low-pressure expansion stage, in which the pressure is released to at least 3 bar, is DE 100 28 637 described. In this case, the loaded absorption liquid is first in a first Niederdruckentspannungsstufe to a pressure of 1 to 2 bar (absolute) relaxed. Subsequently, the partially regenerated absorption liquid is heated in a heat exchanger and then expanded again in a second low-pressure expansion stage to a pressure of 1 to 2 bar (absolute).

The last expansion stage can also be carried out under vacuum, which is produced, for example, by means of a steam radiator, optionally in combination with a mechanical vacuum generator, as described in EP-A 0 159 495, EP-A 0 202 600, EP-A 0 190 434 and EP-A 0 121 109 ( US 4,551,158 ).

Because of the optimum balance of the content of the amine components points the absorbent according to the invention a high loadability with acidic gases, which is also easy again can be desorbed. Thereby can in the inventive method the energy consumption and the solvent circulation be significantly reduced.

The inventive method is described below with reference to 1 and 2 explained.

In 1 schematically a device is shown, in which the absorption stage is carried out in one stage and the relaxation stage in two stages. The feed gas is via line 1 in the lower area of the absorber 2 fed. At the absorber 2 it is a column packed with packing to effect mass and heat exchange. The absorbent, which is a regenerated absorbent having a low residual content of acidic gases, is passed over the line 3 on the head of the absorber 2 abandoned in countercurrent to the feed gas. The depleted in acid gases gas leaves the absorber 2 over head (pipe 4 ). The absorbent enriched with acidic gases leaves the absorber 2 on the ground via pipe 5 and will be in the upper range of high-pressure relaxation column 6 which is generally operated at a pressure which is above the CO ₂ partial pressure of the raw gas supplied to the absorber. The expansion of the absorbent is generally carried out by means of conventional devices, for example a stationary control valve, a hydraulic turbine or a reverse pump. Relaxation releases most of the dissolved non-acidic gases and a small portion of the acidic gases. These gases are via line 7 from the high-pressure expansion column 6 discharged over head.

The absorbent, which is still loaded with most of the acidic gases, leaves the high pressure flash column via line 8th and is in the heat exchanger 9 heated, wherein a small portion of the acidic gases can be released. The heated absorbent is placed in the upper part of a low-pressure expansion column 10 equipped with a packed body in order to achieve a large surface area and thus to effect the release of the CO ₂ and the adjustment of the equilibrium. In the low-pressure expansion column 10 Most of the CO ₂ and H ₂ S are released almost completely by flashing. The absorbent is thus regenerated and cooled simultaneously. At the top of the low pressure relaxation column 10 is a reflux cooler 11 with a collecting container 12 provided to cool the liberated acid gases and to condense a portion of the vapor. The bulk of the sour gas leaves the reflux condenser 11 via wire 13 , The condensate is pumped 14 on the head of the low pressure relaxation column 10 pumped back. The regenerated absorbent, which still contains a small part of the CO ₂ , leaves the low-pressure expansion column 10 on the ground via pipe 15 and is done by pump 16 via wire 3 on the head of the absorber 2 given up. Via wire 17 Fresh water can be fed in to balance the water discharged with the gases.

2 schematically shows an apparatus for carrying out the method according to the invention using a two-stage absorber and a two-stage relaxation. The absorber comprises the raw sorbent 1 and the pure absorber 2 , The feed gas is 20 via wire 3 in the lower area of the Rohabsorber 1 fed and treated in countercurrent with regenerated absorbent, via line 4 on the head of the Rohabsorber 1 is abandoned and still contains some acidic gases. On the head of the pure absorber 2 will be over line 5 abandoned regenerated absorbent, which contains substantially no acid gases. Both parts of the absorber contain a packing to effect the mass and heat exchange between the raw gas and the absorbent. The treated gas leaves the pure absorber 2 over head (pipe 6 ). The absorbent laden with acid gases is at the bottom of the Rohabsorbers 1 discharged and over line 7 in the upper part of the high-pressure expansion column 8th fed. The column 8th is equipped with a packing and is operated at a pressure between the pressure in the absorber and the subsequent low-pressure expansion column 11 lies. The relaxation of the laden with acidic gases absorbent is carried out by means of conventional devices, such as a stationary control valve, a hydraulic turbine or a reverse pump. During high-pressure release, most of the dissolved non-acidic gases and a small portion of the acidic gases are released. These gases are via line 9 from the high-pressure expansion column 8th discharged over head.

The absorbent, which is still loaded with most of the acid gases, leaves the high pressure flash column 8th via wire 10 and enters the top of the low pressure flash column 11 fed, where most of the CO ₂ and H ₂ S are released by flashing. The absorbent is regenerated in this way. The low-pressure expansion column 11 is equipped with a packing to provide a large surface area for heat and mass transfer. At the top of the low pressure relaxation column 11 is a reflux cooler 12 With 20 condensate tank 13 provided to the over head from the low-pressure expansion column 11 To cool escaping acid gases and to condense a portion of the vapor. The uncondensed gas, which contains the major amount of acidic gases, is sent via pipe 14 discharged. The condensate from the condensate tank 13 is over pump 15 on the head of the low pressure relaxation column 11 given up.

The partially regenerated absorbent, which still contains some of the acidic gases, leaves the low-pressure expansion column 11 on the ground via pipe 16 and is split into two sub-streams. The larger partial flow is via pump 17 and direction 4 on the head of the Rohabsorber 1 abandoned, whereas the smaller part over lead 18 by pump 19 in the heat exchanger 20 is heated. The heated absorbent is then placed in the top of the stripper 21 fed, which is equipped with a pack. In the stripper 21 Most of the absorbed CO ₂ and H ₂ S is stripped out by means of steam, which in the reboiler 22 generated and in the bottom of the stripper 21 is fed. That's the stripper 21 on the ground via pipe 23 leaving absorbent has a low residual content of acidic Gases on. It gets over the heat exchanger 20 passed, which from the low-pressure expansion column 11 upcoming, partially regenerated absorbent is heated. The cooled, regenerated absorbent is pumped 24 via heat exchangers 25 back to the head of the leg absorber 2 pumped. Via wire 26 can be on the head of the leg absorber 2 Fresh water to be replaced to replace the discharged through the gas streams water. That from the stripper 21 Gas escaping overhead is sent via line 27 in the lower part of the low-pressure expansion column 11 fed.

experimental part

manufacturing a polyurea amine

360 g of tris (aminoethyl) amine, 147.8 g of urea and 0.5 g of potassium carbonate as a catalyst were in a three-necked flask equipped with stirrer, Reflux cooler and Indoor thermometer, presented and heated with stirring. At 100 -110 ° C sat Gas evolution. The reaction was then within 3 h to 150 ° C heated and 1 h at 150 ° C touched. Subsequently The reaction mixture was cooled to room temperature.

Of the Polyurea amine were by gel permeation chromatography with a Refractometer analyzed as a detector. The mobile phase was hexafluoroisopropanol was used as the standard for determining the molecular weight Polymethyl methacrylate (PMMA) used. The analytics revealed number average molecular weight Mn of 3900 g / mol and a weight average Mw of 10,000 g / mol.

Comparative experiments on the solubility of CO ₂ in aqueous solutions of polyethyleneimine (Lupasol), polyvinylamine (Lupamin) and polyurea amine.

Conditions:

• CO ₂ was bubbled by means of a frit over 4 h with a flow rate of about 20 Nl / h in 100 ml of each aqueous solution to be examined. After 4 h, the CO ₂ loading of the solution was measured.
• Temperatures: 50 ° C u. 90 ° C
• Pressure: ambient pressure, CO ₂ partial pressure = ambient pressure minus vapor pressure of the solvent (essentially water vapor pressure)
  

• Lupasol ^® G 20 (BASF AG). Polyethyleneimine, molecular weight 1300 g / mol
• Lupasol ^® WF (BASF AG, polyethyleneimine, molecular weight 25,000 g / mol
• ^® Lupamin 4595 (BASF AG) polyvinylamine, Molekulargwicht 50000 g / mol

For Lupasol ^® G 20, the concentration in the above table refers to a 50% aqueous solution Solution. 20% and 40% respectively of the 50% solution was used. Of Lupasol ^® WF 20% and 40% of a 99% solution were used. Lupamine and polyurea also used 20% of a 99% solution.

The CO ₂ could be removed by boiling under total reflux at ambient pressure for the most part again from the aqueous polymer solutions. From the loaded at 50 ° C and at 90 ° C 40 wt .-% solutions of Lupasol G20 and Lupasol WF, a mixture was prepared and this boiled for 3 h or 6 h. The following residual loads were determined. Load Nm ³ / tLsgm. Mixture boiled for 3 h 4.9 Boiled out for 6 h 3.6

It was a further series of experiments for loading and residual loading after stripping with N ₂ in aqueous solutions of polyamine A as a comparative experiment (20 and 40 wt .-%, balance water), aqueous solutions of monomer A as comparative experiments and mixtures of polyamine A and monomer B performed as an inventive experiment at 70 ° C.

Conditions:

• Druck: Umgebungsdruck, CO₂-Partialdruck = Umgebungsdruck minus Dampfdruck des Absorptionsmittels, also hauptsächlich der Dampfdruck des Wassers
• Temperatur: 70°C,

Zusammensetzungen der Lösungen: siehe Tabelle

MAPA

= 3-Methylaminopropylamin

MDEA

= N-Methyldiethanolamin

MEA

= Monoethanolamin

DEA

= Diethanolamin

• Lupasol^® FC (BASF AG). Polyethylenimin, Molekulargewicht 800 g/mol
• Lupasol^® G 20 (BASF AG). Polyethylenimin, Molekulargewicht 1300 g/mol
• Lupasol^® G 35 (BASF AG). Polyethylenimin, Molekulargewicht 2000 g/mol
• Lupasol^® FG (BASF AG). Polyethylenimin, Molekulargewicht 800 g/mol

CO ₂ was bubbled by means of a frit over 4 h with a flow rate of about 20 Nl / h in 100 ml of each aqueous solution to be examined. After 4 h, the CO ₂ loading of the solution was measured. Then, the solution was heated to 100 ° C and with an N ₂ stream of 10 Nl / h for 15 min. stripped. Thereafter, the CO ₂ load was also measured. The results are shown in the following table. The difference between the two measured values is the so-called CO ₂ stroke. This parameter is particularly meaningful, because it shows how much CO ₂ can be removed when passing through an absorption-desorption cycle with a defined amount of absorbent and is thus a measure of the efficiency of the process.

• Pressure: ambient pressure, CO ₂ partial pressure = ambient pressure minus vapor pressure of the absorbent, ie mainly the vapor pressure of the water
• Temperature: 70 ° C,

Compositions of solutions: see table

MAPA

= 3-methylaminopropylamine

MDEA

= N-methyldiethanolamine

MEA

= Monoethanolamine

DEA

= Diethanolamine

• Lupasol ^® FC (BASF AG). Polyethyleneimine, molecular weight 800 g / mol
• Lupasol ^® G 20 (BASF AG). Polyethyleneimine, molecular weight 1300 g / mol
• Lupasol ^® G 35 (BASF AG). Polyethyleneimine, molecular weight 2000 g / mol
• Lupasol ^® FG (BASF AG). Polyethyleneimine, molecular weight 800 g / mol

The Concentration data for the Lupasol marks in the table refer to the concentration of each used Lupasol solution.

The solutions were used in the following concentrations:
Lupasol ^® G20: 50 wt .-% solution
Lupasol ^® FC: 50 wt .-% solution
Lupasol ^® G35: 50 wt .-% solution
Lupasol ^® FG: 99 wt .-% solution
Lupasol ^® WF: 99 wt .-% solution
Polyurea: 99% by weight solution

This results in, for example, for the table statement: 20% Lupasol ^® G35 that 10% of polymer in the test solution were as Lupasol G35 was used as a 50% aqueous solution.

Furthermore, mass transfer coefficients for CO ₂ in aqueous solutions of a polymer amine A and 3-methylaminopropylamine (experiments according to the invention) were determined in a laminar jet chamber. The values determined were compared with mass transfer coefficients of CO ₂ in aqueous solutions of N-methyldiethanolamine and 3-methylamino-propylamine.

In determining the mass transfer coefficient, the amount of absorbed gas is measured on a liquid jet of known surface. The gas-side mass transfer coefficient can be neglected because the CO ₂ gas phase concentration kept constant during the measurement is large. Therefore, this measurement provides good comparative values of the rate at which CO ₂ is absorbed in the liquid. Apparatus and method are described, for example, in Danckwerts, PV, Gas Liquid Reactions, McGraw-Hill, 1970.

compositions the solutions and determined mass transfer coefficients at 70 ° C are shown in the following table.

The Results suggest that high levels of Lupasol (Polymer amine A) due to the increased viscosity the reactive absorption processes run somewhat slower than in the mixture, with the tertiary alkanolamine MDEA (monomer amine B) while at lower polymer content of the disadvantage of higher viscosity an excess of reactive amine groups compared to MDEA more than is compensated.

Claims (11)

A process for deacidifying a fluid stream, the Contains acid gases as an impurity, wherein in at least an absorption step, the fluid flow with an absorbent containing a) 0.3 to 60 wt .-% of a polyamine with at least 2 primary, secondary or tertiary Amino groups and a molecular weight of more than 200 g / mol (Polymeramin A) b) 0.1 to 70 wt .-% of an aliphatic or cycloaliphatic Amines with a molecular weight of 200 g / mol or less (monomer amine B) c) and optionally 1 to 90 wt .-% water brings in contact, wherein a loaded with the sour gas absorbent and a purified Fluid flow is formed, and the purified fluid stream and the with the sour gas loaded absorbent separated from each other. The method of claim 1, wherein the fluid stream comprises - natural gas - Syngas - Liquefied Petroleum gas - Claus Tail gas - Refinery gas - one Gas stream formed during the oxidation of organic substances becomes - one Gas stream used in the composting and storage of organic substances containing wastes is formed - a gas stream, at the bacterial decomposition organic substances is formed. Method according to one of the preceding claims, wherein the polymer amine A comprises: polyvinylamines, polyvinylamidoamines, Polyethyleneimines, polypropyleneimines, polyamidoamines, polyureasamines. A process according to any one of the preceding claims, wherein the polymer amine A has a weight average molecular weight (M _w ) of from 200 to 3,000,000 g / mol. Method according to one of the preceding claims, wherein the polymer amine A5 to 35 moles of amino groups per kg. Method according to one of the preceding claims, wherein passing through the loaded with the acid gas absorbent - Heating, - relaxation, - Stripping with an inert fluid - or a combination of several of the above measures regenerated. A process according to any one of the preceding claims, wherein the sour gas is CO ₂ , H ₂ S, SO ₂ , SO ₃ , CS ₂ , HCN, hydrogen halides, COS or mercaptans. Process according to claim 6, wherein the absorption agent after relaxing by stripping with an inert fluid, in particular Nitrogen or water vapor, regenerated. Method according to one of the preceding claims, wherein to bring in contact in several consecutive sub-steps and the sauergashaltigen fluid flow in each of the substeps, respectively a partial flow absorbent brings into contact. A process according to any one of the preceding claims, wherein the purified fluid stream contains less than 500 ppm by weight of CO ₂ and less than 10 ppm by weight of H ₂ S. Absorbent containing a) 0.3 to 60 Wt .-% of a polyamine having at least 2 primary, secondary or tertiary amino groups and a molecular weight of more than 200 g / mol (polymer amine A), b) 0.1 to 70 wt .-% of an aliphatic or cycloaliphatic amine having a molecular weight of 200 g / mol or less (monomer amine B) c) and optionally 1 to 90 wt .-% water.