Classifications

• • 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
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/755—Nickel
• • 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
  • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
  • B01J21/18—Carbon
• • 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
  • B01J35/00—Catalysts, in general, characterised by their form or physical properties
  • B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
  • B01J35/45—Nanoparticles
• • 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
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0207—Pretreatment of the support
• • 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
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/16—Reducing
  • B01J37/18—Reducing with gases containing free hydrogen
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
  • C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
  • C07C29/60—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by elimination of -OH groups, e.g. by dehydration
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C31/00—Saturated compounds having hydroxy or O-metal groups bound to acyclic carbon atoms
  • C07C31/18—Polyhydroxylic acyclic alcohols
  • C07C31/20—Dihydroxylic alcohols
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P20/00—Technologies relating to chemical industry
  • Y02P20/50—Improvements relating to the production of bulk chemicals
  • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

• the invention relates to a hydrogenation catalyst containing nickel supported on carbon, processes for the preparation of the hydrogenation catalyst and its use for the hydrogenation of sorbitol to glycols or for the hydrogenation of glucose to sorbitol.
• glycols such as propylene glycol and ethylene glycol starting from maize
• first starch is obtained from the maize, which is subsequently converted into glucose, then sorbitol and then glycols such as propylene glycol and ethylene glycol.
• polymer resins such as polyurethanes or for the preparation of polymer crosslinkers and other chemical compounds.
• the hydrogenation of sorbitol to glycols such as ethylene glycol and propylene glycol is carried out at high temperatures and pressures and high pH in an aqueous medium.
• inorganic carriers used for hydrogenation catalysts generally do not or only for a short time withstand these conditions, so that such catalysts are not suitable for the hydrogenation of sorbitol.
• catalysts have been proposed which contain nickel and rhenium on a carbon support.
• US Pat. No. 6,841,085 describes the hydrogenation of sugars such as sorbitol to predominantly ethylene glycol and propylene glycol, using a catalyst comprising 2.5% by weight of nickel and 2.5% by weight of rhenium on a coconut carbon support.
• the support is first impregnated with metal salt solutions of the active metals, subsequently dried and reduced at 280 ° C for 16 hours.
• the object of the present invention is to provide hydrogenation catalysts, in particular for the hydrogenation of sorbitol to glycols, which withstand high temperatures and pressures and an aqueous environment with high pH values and can be prepared in a simple and cost-effective manner. They should show a preferred selectivity for propylene glycol and optionally ethylene glycol.
• the object is achieved by a hydrogenation catalyst containing 1 to 50 wt .-%, based on the total catalyst, of nickel on a support of carbon, wherein the hydrogenation catalyst does not contain rhenium.
• hydrogenation catalysts are suitable for the hydrogenation of sorbitol to glycols which contain nickel but not rhenium as active metal on a carbon support.
• the catalysts are accessible in a simple manner, since it only has to be impregnated with an active metal. In addition, they are significantly less expensive than known catalysts because they dispense with the use of expensive rhenium and use inexpensive carbon support.
• the catalyst according to the invention contains no rhenium. This means that no technically effective amounts of rhenium are contained in the catalyst and thus rhenium has no significance as an active metal.
• catalysts which contain only nickel as the active metal.
• further active metals such as molybdenum, vanadium or tin and mixtures thereof in addition to nickel.
• the catalyst of the invention contains nickel in an amount of 1 to 50 wt .-%, preferably 5 to 40 wt .-%, in particular 10 to 30 wt .-%, based on the total catalyst.
• the proportion of other metals is 0 to 25 wt .-%, preferably 0 to 15 wt .-%, in particular 0 to 5 wt .-%. If such metals are present, their minimum amount is preferably 0.5 wt .-%.
• no further active metals are particularly preferably present on the catalyst support. More preferably, only nickel is present as the active metal on the catalyst support. In particular, the carbon support is impregnated only with nickel as the metal.
• Any suitable carbon support can be used according to the invention.
• coconut shells, olive pits or peat coal can be used as carbon carriers. It is also possible to use synthetic carbon carriers. Coconut shell carbon is particularly preferably used as support.
• the carbon support can be used untreated or pretreated to prepare the catalyst.
• a pretreatment of the carbon is possible for example by heat, steam, acids or chemical pretreatment.
• a steam pretreatment of the coconut shell carbon is carried out with steam.
• the carrier may have any suitable particle size.
• the support preferably has an average particle diameter in the range from 0.5 to 5 mm, particularly preferably 0.75 to 3.5 mm, in particular 1 to 2 mm.
• the hydrogenation catalyst used according to the invention can be prepared by any suitable method. Usually, it is prepared by impregnating the carrier with a nickel salt solution, then drying and then reducing. The reduction is preferably carried out at a temperature above 300 ° C, more preferably in the range of about 300 ° C to 700 ° C, in particular in the range of 400 to 600 ° C, especially in the range of 400 to 500 ° C. For example, the reduction treatment may be carried out at about 500 ° C.
• the invention also relates to a catalyst which can be prepared by the above process.
• the invention also relates to a process for preparing the above catalyst by impregnating the support of carbon with a nickel salt solution, then drying the impregnated support and subsequently reducing the dried support at a temperature above 300 ° C.
• the abovementioned reduction temperatures are preferably used.
• Impregnation may be by any suitable impregnation method. Preferably, a vacuum impregnation is carried out. It can be assumed that any suitable nickel salts. Nickel nitrate is preferably used as the aqueous solution.
• the drying is preferably carried out at a temperature in the range of 50 to 150 ° C at normal pressure or preferably at reduced pressure. Most preferably, it is dried under vacuum or reduced pressure.
• the reduction is preferably carried out in the presence of a gas containing free hydrogen, in particular in a hydrogen atmosphere.
• the reduction may be followed by stabilization of the nickel-containing catalyst, for example in air at room temperature, in order to arrive at a storable stable nickel catalyst.
• Typical hydrogenation conditions in the hydrogenation of sorbitol are a temperature in the range of 150 to 350 ° C, preferably 200 to 300 ° C, in particular about 250 ° C, a hydrogen pressure in the range of 50 to 300 bar, in particular of about 150 bar, a Sorbitol concentration of 10 to 40 wt .-% in water, especially about 20 wt .-% in water, a starting pH in the range of 12 to 13, for example, adjusted by the addition of KOH.
• sorbitol is usually carried out at a temperature of 250 ° C, a hydrogen pressure of 150 bar, a pH of 12 to 13 to a 20 wt .-% - aqueous sorbitol solution.
• the degree of reduction of the sorbitol is preferably in the range of 50 to 99%.
• the strength of the catalysts is determined.
• the carbon carriers in particular the coconut shell carbon carriers, there is no reduction of the starch by the hydrogenation.
• the catalysts of the invention are thus preferably used for the hydrogenation of sorbitol to glycols, in particular propylene glycol and ethylene glycol, with small amounts of glycerol, or for the hydrogenation of glucose to sorbitol.
• the invention thus also relates to a process for the preparation of glycols by hydrogenation of sorbitol, in which the hydrogenation is carried out on a catalyst as described above.
• the invention relates to a process for the preparation of sorbitol by hydrogenation of glucose, wherein the hydrogenation is carried out on a catalyst as described above.
• the hydrogenation is preferably carried out continuously, wherein the hydrogenation catalyst is present as a fixed bed.
• the catalysts according to the invention have an improved selectivity with regard to the production of propylene glycol.
• the selectivity is very high especially for nickel catalysts with coconut shell carbon carriers.
• the conversion and selectivity to propylene glycol and ethylene glycol are significantly better for the nickel-containing hydrogenation catalyst according to the invention than for a comparative catalyst which additionally contains rhenium. Both conversion and propylene glycol selectivity were significantly better for a 10 wt% nickel-supported catalyst than for a catalyst containing 10 wt% nickel and 1 wt% rhenium on the same carbon support.
• the reaction is preferably carried out at a temperature in the range of 50 to 250 ° C, more preferably 90 to 140 ° C, a pressure in the range of 30 to 250 bar, particularly preferably 60 to 150 bar and a glucose concentration in the preferably aqueous glucose solution in the range of 30 to 70% by weight, more preferably 40 to 60% by weight.
• the space velocity is preferably 0.15 to 2 l / l ⁇ hr.
• a base addition is typically not required. After about 300 hours, the strength of the catalysts in the fixed bed had not changed.
• the catalysts according to the invention have an improved selectivity and activity with respect to the preparation of Sorbitol on.
• the selectivity is very high, especially for nickel catalysts and coconut shell carbon carriers.
• Example 1 Preparation of the catalyst
• the starting materials used were carbon extrudates or carbon granules.
• coconut shell carbon was preferably used, as described by Japan EnviroChemicals Ltd. is available under the name SHIRASAGI C2X8 / 12. This carbon has a bulk density of about 0.5 g / ml and an average particle size of 1.8 mm.
• a nickel nitrate-containing aqueous solution was prepared in deionized water having, for example, a nickel concentration of 14.4% by weight.
• deionized water having, for example, a nickel concentration of 14.4% by weight.
• 53.3 g of Ni (NO 3 ) 2 .6 H 2 O in 22.0 g of water were used to impregnate 50 g of carbon extrudates.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Catalysts (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

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• 2012
  • 2012-01-18 JP JP2013549918A patent/JP2014507270A/ja active Pending
  • 2012-01-18 KR KR1020137022141A patent/KR20140004733A/ko not_active Withdrawn
  • 2012-01-18 EP EP12739450.0A patent/EP2668148A1/de not_active Withdrawn
  • 2012-01-18 CN CN2012800063705A patent/CN103339093A/zh active Pending
  • 2012-01-18 CA CA2823676A patent/CA2823676A1/en not_active Abandoned
  • 2012-01-18 WO PCT/IB2012/050243 patent/WO2012101550A1/de not_active Ceased

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