Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
  • C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
  • C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
  • C07C51/215—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of saturated hydrocarbyl groups
• • 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
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/56—Platinum group metals
  • B01J23/64—Platinum group metals with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/652—Chromium, molybdenum or tungsten
  • B01J23/6527—Tungsten
• • 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
  • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
  • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/66—Silver or gold
  • B01J23/68—Silver or gold with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/683—Silver or gold with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with chromium, molybdenum or tungsten
  • B01J23/687—Silver or gold with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with chromium, molybdenum or tungsten with tungsten
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
  • C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
  • C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
  • C07C51/25—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of unsaturated compounds containing no six-membered aromatic ring

Definitions

• the present invention relates to a process for the selective production of acetic acid by catalytic gas phase oxidation of ethane and / or ethylene in the presence of a catalyst containing tungsten, and the catalyst.
• US-A-4250 346 discloses the use of a catalyst composition containing the elements molybdenum, X and Y in the ratio a: b: c for converting ethane to ethylene, where X is Cr, Mn, Nb, Ta, Is Ti, V, and / or W, and
• Y is Bi, Ce, Co, Cu, Fe, K, Mg, Ni, P, Pb, Sb, Si, Sn, Tl and / or U, and a is 1, b is 0.05 to 1 and c is Is 0 to 2.
• the total value of c for Co, Ni and / or Fe must be less than 0.5.
• the catalysts disclosed can also be used for the oxidation of ethane to acetic acid, the efficiency of the conversion to acetic acid being about 18%, with an ethane conversion of 7.5%.
• EP-A-0294 845 discloses a process for the selective production of acetic acid from ethane, ethylene or mixtures thereof with oxygen in the presence of a catalyst mixture containing
• the second catalyst component B is in particular a molecular sieve catalyst or a palladium-containing oxidation catalyst.
• the maximum selectivity that can be achieved is 27% with an ethane conversion of 7%.
• EP-A-0 294 845 the high conversion rates of ethane are achieved only with the catalyst mixture described, but not with a single catalyst containing components A and B.
• EP-A-0 407 091 discloses a process for the preparation of a mixture of ethylene and / or acetic acid.
• ethane and / or ethylene and a gas containing molecular oxygen are brought into contact at elevated temperature with a catalyst composition which contains the elements A, X and Y.
• A here is Mo / Re / W
• X is Cr, Mn, Nb, Ta, Ti, V and / or W
• Y is Bi, Ce, Co, Cu, Fe, K, Mg, Ni, P, Pb, Sb , Si, Sn, Tl and / or U.
• the maximum selectivities that could be achieved when using the catalyst described in the oxidation of ethane to acetic acid are 78%.
• Carbon dioxide, carbon monoxide and ethylene are formed as further by-products.
• catalysts which contain molybdenum are disadvantageous because molybdenum forms volatile molybdenum compounds under the prevailing reaction conditions, which leads to a decrease in the activity and selectivity of the catalyst.
• the object was therefore to provide a process by which ethane and / or ethylene can be oxidized to acetic acid in a simple manner, in a targeted manner and with high selectivity under the mildest possible reaction conditions.
• the present invention thus relates to a process for the selective production of acetic acid from a gaseous feed from ethane, ethylene or mixtures thereof as well as oxygen or oxygen-containing gases at elevated temperature on a catalyst containing tungsten which contains the elements W, X, Y and Z in the Contains gram atom ratios a: b: c: d in combination with oxygen
• X is one or more elements selected from the group Pd, Pt, Ag and / or Au,
• Y one or more elements selected from the group V, Nb, Cr, Mn, Fe,
• Z one or more elements selected from the group Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr, Hf, Ru, Os, Co, Rh, Ir , B, AI, Ga, In, Tl, Si, Ge,
• X preferably denotes Pd
• Y preferably denotes V, Nb, Sb and / or Cu
• Z preferably denotes K, Ca, Si and / or P.
• indices b, c and d can also assume several different values.
• the present invention relates to a catalyst for selective Production of acetic acid containing the elements W, X, Y and Z in gram atom ratios a: b: c: d in combination with oxygen.
• stoichiometric indices b, c and d are preferably 0.0001 to 0.5; c 0.1 to 1.0 and d 0.001 to 1.0.
• Values of b which are above the preferred range can lead to a favored formation of carbon dioxide in the process according to the invention.
• the preferred values for b enable the invention to be carried out particularly economically.
• the catalyst according to the invention contains, in addition to the elements tungsten and palladium, vanadium, niobium and / or antimony and calcium in combination with oxygen.
• the catalysts of the invention can be prepared by the processes described in the prior art. For this, one starts with a slurry, in particular an aqueous solution, which the individual
• the starting materials for the individual components for the preparation of the catalyst according to the invention are preferably water-soluble substances such as ammonium salts, nitrates, sulfates, halides, hydroxides and salts of organic acids which can be converted into the corresponding oxides by heating.
• water-soluble substances such as ammonium salts, nitrates, sulfates, halides, hydroxides and salts of organic acids which can be converted into the corresponding oxides by heating.
• aqueous solutions or suspensions of the metal compounds are prepared and mixed.
• reaction mixture obtained is then stirred at 50 to 100 ° C. for 5 minutes to 5 hours.
• the water is then removed and the remaining catalyst is dried at a temperature of 50 to 150 ° C., in particular 80 to 120 ° C.
• the dried and pulverized catalyst at a temperature in the range from 100 ° C. to 800 ° C., in particular 200 to 500 ° C. in the presence of nitrogen, oxygen or to calcine an oxygen-containing gas.
• the duration of the cleavage is preferably 2 to 24 hours.
• the catalyst can be used without an appropriate support material or mixed with or applied to one.
• Suitable carrier materials such as, for example, porous silicon dioxide, are suitable for annealing Silicon dioxide, diatomaceous earth, silica gel, porous or non-porous aluminum oxide, titanium dioxide, zirconium dioxide, thorium dioxide, lanthanum oxide, magnesium oxide, calcium oxide, barium oxide, tin oxide, cerium dioxide, zinc oxide, boron oxide, boron nitride, boron carbide, boron phosphate, zirconium phosphate, aluminum silicate or silicon nitride, also silicon nitride Glass, carbon fiber, metal oxide or metal networks or corresponding monoliths.
• the catalyst is applied to a support, this can be done by dry or wet impregnation of the support with the dissolved or suspended components of the catalyst. Another possibility is to mix the solutions or suspensions of the catalyst components with a sol of the support material and then to subject them to spray drying. In both cases, it can then be calcined as described.
• Preferred carrier materials have a surface area of less than 100 m 2 / g.
• Preferred carrier materials are silicon dioxide and aluminum oxide with a low specific surface area.
• the catalyst can be used as a regularly or irregularly shaped support body, in powder form or in the above-mentioned forms as a heterogeneous oxidation catalyst.
• the reaction can be carried out in the fluidized bed or in a fixed bed reactor.
• the catalyst is usually ground to a particle size in the range from 10 to 200 ⁇ m or produced by spray drying.
• the gaseous feed contains ethane and / or ethylene, which are fed to the reactor as pure gases or as a mixture with one or more other gases.
• additional or carrier gases are nitrogen, methane, carbon monoxide, carbon dioxide, air and / or water vapor.
• the molecular oxygen-containing gas can be air or a molecular one
• Oxygen is richer or poorer gas than air, for example pure oxygen.
• the proportion of water vapor can range from 0 to 50 vol%. Higher water vapor concentrations would work up the resulting aqueous For procedural reasons, acetic acid becomes unnecessarily expensive, but is technically possible.
• the molar ratio of ethane / ethylene to oxygen is preferably in the range between 1: 1 and 10: 1, in particular 2: 1 and 8: 1. Higher oxygen contents are preferred because the achievable ethane conversion and thus the yield of acetic acid is higher. It is preferred to add oxygen or the molecular oxygen-containing gas in a concentration range outside the explosion limits under reaction conditions, since this simplifies the implementation of the process. However, it is also possible to set the ethane / ethylene / oxygen mixture within the explosion limits.
• the reaction is generally carried out at temperatures between 200 and 500 ° C., preferably 200 to 400 ° C.
• the pressure can be atmospheric or super-atmospheric, e.g. in the range between 1 and 50 bar, preferably 1 to 30 bar.
• the reaction can be carried out in a fixed bed or fluidized bed reactor.
• ethane is first mixed with the inert gases such as nitrogen or water vapor before oxygen or the gas containing molecular oxygen is added.
• the mixed gases are preferably preheated to the reaction temperature in a preheating zone before the
• Gas mixture is brought into contact with the catalyst.
• Acetic acid is separated from the reactor offgas by condensation.
• the remaining gases are returned to the reactor inlet, where oxygen or the gas containing molecular oxygen and ethane and / or ethylene are metered in.
• Catalyst (I) A catalyst with the following composition was produced: 1.00 Pd 0.0005 V 0.25 Nb 0.12
• the water is then evaporated and the evaporated residue is dried at 120 ° C. overnight.
• the solid is crushed (sieve fraction ⁇ 2 mm) and then heated to 400 ° C. under an air stream at a heating rate of 2 ° C. per minute. The temperature is held for four hours. The airflow is turned off and the material is slowly cooled.
• the catalyst is mortarized and pressed (pressing pressure 2 tons) and sieved in order to obtain a sieve fraction between 0.35 and 0.7 mm.
• the solid is crushed (sieve fraction ⁇ 2 mm) and then heated under air flow to 400 ° C at a rate of 2 ° C per minute. The temperature is held for four hours. The airflow is turned off and the material is slowly cooled. The catalyst is ground and pressed (pressure 2 tons) and sieved to obtain a sieve fraction between 0.35 and 0.7 mm.
• Heating rate of 2 ° C per minute The temperature is held for four hours. The airflow is turned off and the material is slowly cooled. The catalyst is mortarized and pressed (pressing pressure 2 tons) and sieved in order to obtain a sieve fraction between 0.35 and 0.7 mm.
• W 1.00 Pd O, 0004 V 0.50 Nb O, 2 Cu O, 10 P 0.05 100 g of ammonium meta-tungstate are suspended in 500 ml of water at 90 ° C.
• a solution of 22.4 g of ammonium metadvanadate in 250 ml of water at 90 ° C. is added dropwise to this mixture.
• the combined mixtures are stirred at 90 ° C. for 15 minutes.
• a suspension of 59.5 g of niobium oxalate, 8.91 g of copper nitrate and 1.6 g of phosphoric acid is then added dropwise to this mixture
• Heating rate of 2 ° C per minute The temperature is held for four hours. The airflow is turned off and the material is slowly cooled.
• the catalyst is mortarized and pressed (pressure 2 tons) and sieved to a sieve fraction to get between 0.35 and 0.7 mm.
• the reactor inlet gas consisted of 40 vol% ethane, 8 vol% oxygen, 32 vol% nitrogen and 20 vol% water vapor.
• the reaction conditions and results are summarized in the table below.

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• Organic Chemistry (AREA)
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• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Catalysts (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

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• 1997
  • 1997-04-23 DE DE19717076A patent/DE19717076A1/de not_active Withdrawn
• 1998
  • 1998-04-11 JP JP54494298A patent/JP4006029B2/ja not_active Expired - Fee Related
  • 1998-04-11 CN CN98804455A patent/CN1090605C/zh not_active Expired - Lifetime
  • 1998-04-11 CA CA002288276A patent/CA2288276C/en not_active Expired - Lifetime
  • 1998-04-11 ES ES98922688T patent/ES2172145T3/es not_active Expired - Lifetime
  • 1998-04-11 EP EP98922688A patent/EP0979222B1/de not_active Expired - Lifetime
  • 1998-04-11 US US09/403,516 patent/US6274765B1/en not_active Expired - Lifetime
  • 1998-04-11 WO PCT/EP1998/002124 patent/WO1998047850A1/de not_active Ceased
  • 1998-04-11 DE DE59803069T patent/DE59803069D1/de not_active Expired - Lifetime
  • 1998-04-21 MY MYPI98001774A patent/MY119225A/en unknown
  • 1998-09-06 SA SA98190500A patent/SA98190500B1/ar unknown
• 1999
  • 1999-10-18 NO NO19995085A patent/NO326454B1/no not_active IP Right Cessation

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