EP0931048A1 - Procede pour la fabrication d'une matiere a action catalytique constituee d'oxydes de plusieurs metaux - Google Patents

Procede pour la fabrication d'une matiere a action catalytique constituee d'oxydes de plusieurs metaux

Info

Publication number
EP0931048A1
EP0931048A1 EP97942001A EP97942001A EP0931048A1 EP 0931048 A1 EP0931048 A1 EP 0931048A1 EP 97942001 A EP97942001 A EP 97942001A EP 97942001 A EP97942001 A EP 97942001A EP 0931048 A1 EP0931048 A1 EP 0931048A1
Authority
EP
European Patent Office
Prior art keywords
calcination
multimetal oxide
methacrolein
methacrylic acid
vol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP97942001A
Other languages
German (de)
English (en)
Inventor
Heiko Arnold
Friedrich-Georg Martin
Hermann Petersen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BASF SE
Original Assignee
BASF SE
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BASF SE filed Critical BASF SE
Publication of EP0931048A1 publication Critical patent/EP0931048A1/fr
Ceased legal-status Critical Current

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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
    • C07C51/25—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of unsaturated compounds containing no six-membered aromatic ring
    • C07C51/252—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of unsaturated compounds containing no six-membered aromatic ring of propene, butenes, acrolein or methacrolein
    • 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
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • 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
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/14—Phosphorus; Compounds thereof
    • B01J27/186—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J27/195—Phosphorus; Compounds thereof with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium with vanadium, niobium or tantalum
    • B01J27/198—Vanadium
    • B01J27/199—Vanadium with chromium, molybdenum, tungsten or polonium
    • 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
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts

Definitions

  • the present invention relates to a process for producing a catalytically active multimetal oxide composition of the general formula I xa 1 xb 2 x 3 cxd 4 xe 5 sbf on (i;
  • the present invention relates to the multimetal oxide compositions obtainable using the process according to the invention and to their use as catalysts for the gas-phase catalytic oxidative production of methacrylic acid from methacrolein.
  • Catalytically active multimetal oxide compositions of the general formula I and their use as catalysts for the gas-phase catalytic oxidative production of methacrylic acid from methacrolein are known (cf., for example, DE-A 43 29 907). They are usually produced by producing an intimate, preferably finely divided, dry mixture from sources of their elemental constituents and calcining them at temperatures of 150 ° C. to 450 ° C.
  • sources which are particularly suitable for the preparation of catalytically active multimetal oxide compositions I are those starting compounds which contain ammonium ions.
  • Preferred sources of molybdenum are, for example, the ammonium salt of molybdic acid and the ammonium salt of
  • a favorable source of vanadium is ammonium vanadate and advantageous sources of phosphorus or sulfur form the di-ammonium phosphate or ammonium sulfate.
  • EP-B 442 517 it is also very generally advantageous to use compounds such as ammonium carbonate, ammonium hydrogen carbonate, ammonium sulfate and ammonium hydrogen sulfate in the production of multimetal oxide compositions of the general formula I.
  • a content of NH 3 in the calcination atmosphere has an effect within the scope of Production of at least one element X 1 and at least one element X 2 and antimony-containing catalytically active multimetal oxide compositions on the resulting catalyst activity (with respect to the catalytic gas phase oxidation of methacrolein to methacrylic acid) advantageously.
  • the above does not apply to multimetal oxide compositions of the general formula I which additionally contain the element V and / or niobium.
  • a process for the preparation of a catalytically active multimetal oxide composition of the general formula I in which one produces the most intimate, preferably finely divided, dry mixture of at least partially sources of elemental constituents containing ammonium ions, and this at temperatures of 150 ° C. to 450 ° C. in one calcined molecular oxygen-containing calcination atmosphere, which is characterized in that the calcination takes place in such a calcination atmosphere, the NH content of which during the entire calcination period ⁇ . 0.75 vol .-% and their molecular 0 2 content during the entire calcination period> . 5 vol .-% is.
  • the calcination is preferably carried out in such a calcination atmosphere, the NH 3 content of which during the entire calcination period is ⁇ 0.5, advantageously ⁇ .0.25, with particular advantage £ 0.1 and with very particular advantage ⁇ .0.05 vol. -%.
  • the content of molecular 0 2 in the calcination atmosphere is preferably> 5 to ⁇ 25 vol.
  • the residual amount of the calcination atmosphere preferably consists of inert gases such as N 2 or noble gases. The duration of the calculation usually extends to a few hours.
  • Senarmontite is preferably used as the source of antimony for at least 25% and particularly preferably for at least 50% of the Sb contained in the multimetal oxide compositions I.
  • the process according to the invention also includes the production of such multimetal oxide compositions, for the production of which at least 80% of the Sb contained is added as senarmontite.
  • 1 to 10% of the total Sb contained in the multimetal oxide compositions I according to the invention is in an amorphous environment.
  • the senarmontite to be used for producing the multimetal oxide compositions I according to the invention is advantageously used in finely divided form.
  • the large diameters are expediently> 0 to ⁇ 50 ⁇ m. However, they can also be 0.1 to 25 or 0.5 to 5 ⁇ m.
  • Other sources of the constituents of the multimetal oxide compositions of the general formula I are oxides or compounds which can be converted into oxides by heating in the presence of oxygen.
  • oxides halides, nitrates, formates, oxalates, acetates, carbonates or hydroxides are therefore particularly suitable as starting compounds.
  • Possible starting compounds of Mo and V are also their tungstates and vanadates or the acids derived from them.
  • element Sb in addition to senarmontite as an element source, valentinite and / or simple salts of Sb such as antimony nitrate are also considered.
  • the intimate mixing of the starting compounds can take place in dry or in wet form. If it is carried out in dry form, the starting compounds are expediently used as finely divided powders and, for example, after mixing, are shaped (for example tableted) to form catalyst bodies which are then subjected to the calcination according to the invention. However, the calcination according to the invention can also take place before the shaping. However, the intimate mixing is preferably carried out in wet form.
  • the starting compounds are usually mixed together in the form of a solution and / or suspension. It is advantageous if the senarmontite used as the starting compound does not dissolve if possible.
  • Z wecktic thus the multi according to the invention obtainable are metal oxides of the general formula Iush- as unsupported catalysts sets, that is, which consist as such catalyst body exclusively from the inventive composition.
  • Hollow cylinders with an outer diameter and a length of 4 to 10 mm and a wall thickness of 1 to 3 mm form the preferred catalyst geometry.
  • An aqueous mixture of the starting components can additionally be used as auxiliary in amounts of 1 to 20% by weight, based on the calcined catalyst mass, of organic compounds such as cyclic compounds containing nitrogen, e.g. Pyridine, but also contain carboxylic acids or alcohols. Drying from wet, usually aqueous, mixture is usually carried out at 60 to 180 ° C. Methods known per se, such as tableting, extrusion or extrusion molding, can be used to form the catalyst mass or its non-calcined precursor mass, whereby lubricants such as graphite or stearic acid as well as molding aids and reinforcing agents such as microfibers made of glass, asbestos, silicon carbide or Potassium titanate can be added.
  • lubricants such as graphite or stearic acid as well as molding aids and reinforcing agents such as microfibers made of glass, asbestos, silicon carbide or Potassium titanate can be added.
  • compositions according to the invention can also be used in the form of supported or coated catalysts, i.e. applied to a preformed, essentially inert, material for the production of methacrylic acid by gas phase oxidation of methacrolein, the application to the essentially inert material e.g. in the form of the aqueous starting solution or suspension, combined with subsequent drying and calcination according to the invention or as pulverized mass which has already been calcined according to the invention in combination with a binder.
  • the multimetal oxide compositions I obtainable according to the invention can of course also be used in powder form as catalysts.
  • the multimetal oxide compositions I obtainable according to the invention are particularly suitable as catalysts for the catalytic gas phase oxidation of methacrolein to methacrylic acid, the methacrylic acid formation taking place with increased activity.
  • the catalytic gas phase oxidation of methacrolein to methacrylic acid using the catalysts obtainable according to the invention is carried out in a manner known per se, i.a. shown in DE-A 40 22 212, way. The same applies to the separation of methacrylic acid from the product gas stream.
  • Oxidizing agent Oxygen can be used in the form of air, for example, but also in pure form. Because of the high heat of reaction, the reactants are preferably diluted with inert gas such as N, CO 2 saturated hydrocarbons and / or with water vapor. With a methacrolein: oxygen: water vapor: inert gas ratio of 1: (1 to 3): (2 to 20): (3 to 30), particularly preferably 1: (1 to 3): (3 to 10): (7 to 18) worked.
  • the methacrolein used can have been obtained in various ways, for example by gas phase oxidation of isobutylene, tert. -Butanol or methyl ether of tert. Butanol.
  • methacrolein which can be obtained by condensing propanal with formaldehyde in the presence of secondary amines and acids in the liquid phase in accordance with the processes described in DE-PS 875 114 or in DE-AS 28 55 514.
  • the gas phase oxidation can be carried out both in fluidized bed reactors and in fixed bed reactors. It is preferably carried out in tube bundle reactors in the tubes of which the catalyst mass, preferably in the form of cylindrically shaped particles, is fixedly arranged.
  • the reaction temperature is generally 250 to 350 ° C
  • the reaction pressure is usually in the range of 1 to 3 bar and the total space load is preferably 800 to 1800 Nl / l / h.
  • the methacrolein conversion in a single reactor pass is usually 50 to 80 mol%.
  • the boundary conditions mentioned are preferably coordinated with one another within the framework of the grid mentioned in such a way that a single passage through the reactor results in a methacrolein conversion of 60 to 70 mol%.
  • the increased activity of methacrylic acid formation when using the masses I obtainable according to the invention as catalysts also exists at methacrolein room loads of more than 60 Nl / l / h.
  • the masses I obtainable according to the invention retain their advantageous properties essentially unchanged over an increased operating time.
  • compositions according to the invention are also capable of gas-phase catalytic oxidation of other organic compounds such as, in particular, other alkanes, alkanols, alkanals, alkenes and alkanols (for example propylene, acrolein, tert. Preferably having 3 to 6 carbon atoms).
  • the low ammonia content of the calcination atmosphere required according to the invention can hardly be achieved in the predominantly used calcination in the tray furnace through which air flows, especially not when larger amounts of catalyst precursors have to be calcined.
  • the calcination according to the invention is therefore preferably carried out on a belt calciner.
  • the calcination material rests in thin layers on endless conveyor belts that run horizontally in the calcination channel.
  • the belts generally consist of sieve belts (close-meshed wire nets), which allow large amounts of hot calcination gases (e.g. hot fresh air) to be passed through the calcination material (suction and / or pressure). Released ammonia is thus led away directly from the calcination material, which results in a calcination atmosphere essentially free of NH 3 .
  • the hot calcination gases can be blown vertically from below as well as obliquely onto the material being passed.
  • the hot calcination gas normally contains inert gases such as N 2 and / or noble gases as a residual amount. Hot air is used as the hot calcination gas in a particularly simple manner.
  • the calcination according to the invention is advantageously designed in several stages.
  • a two-step method of calcination is favorable.
  • the first calcination stage is carried out at a temperature of 150 to 300 ° C, preferably 190 to 280 ° C.
  • the calcination temperature in the second calcination stage is then 350 to 450 ° C, preferably 370 to 400 ° C.
  • the calcination atmosphere comprises at least 5% by volume of 0.
  • the 0 2 content is usually 25% by volume in both calcination stages.
  • the volatile NH 3 has already escaped after the first calculation stage.
  • the developing ammonia must be removed according to the invention in such a way that the calcination atmosphere is particularly preferred in both stages ⁇ 0.75% by volume, better ⁇ 0.5% by volume, preferably ⁇ 0.25% by volume
  • the calcination time in the first calcination step advantageously extends from 0.5 to 1.5 h and the calcination time in the second calcination step advantageously extends from 1 h to 10 h, usually 1 h to 5 h H.
  • the first calcination step is, according to the invention, first of all calcining at about 190 ° C. for about 20 minutes. The mixture is then calcined at 220 ° C. for about 50 minutes and finally again at 270 ° C. for about 50 minutes.
  • the second calcination stage is carried out with particular advantage at about 370 to 400 ° C. for about 3 hours.
  • a support grid extending over the cross section of the pipe was installed in the pipe, to which the catalyst precursor from a) was applied at a bed height of only 5 cm.
  • T 290 ° C.
  • Catalysts A, B, C, D, E and F were obtained in a corresponding manner.
  • the calcined hollow cylinders from c) were pulverized (arithmetically average grain diameter: 1 to 2 mm) and in a tubular reactor (10 mm inner diameter, 100 g catalyst bed, salt bath temperature: 290 ° C.) with a gas mixture of the composition
  • the following table shows the methacrolein conversions achieved in a single pass, depending on the catalysts A, B, C, D, E and F used.
  • a high methacrolein conversion ([number of moles of converted methacrolein / number of moles of methacrolein used] ⁇ 100%) shows a high catalyst activity.
  • the selectivity of methacrylic acid formation ([number of moles of methacrolein converted to methacrylic acid / number of moles of methacrolein total converted 100%) was 88% in all cases.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Catalysts (AREA)

Abstract

L'invention concerne un procédé pour la fabrication de matières constituées d'oxydes de plusieurs métaux contenant du tungstène et ou du molybdène, du soufre, du phosphore, de l'arsenic, du bore, du silicium et/ou du germanium, du vanadium et/ou du niobium ainsi que de l'antimoine et convenant comme catalyseurs pour la conversion par oxydation catalytique en phase gazeuse de méthacroléine en acide méthacrylique. On utilise pour la fabrication de ces matières des sources contenant au moins partiellement des ions ammonium, la calcination s'effectuant dans une atmosphère de calcination amplement dépourvue de NH3.
EP97942001A 1996-09-19 1997-09-09 Procede pour la fabrication d'une matiere a action catalytique constituee d'oxydes de plusieurs metaux Ceased EP0931048A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE1996138249 DE19638249A1 (de) 1996-09-19 1996-09-19 Verfahren zur Herstellung einer katalytisch aktiven Multimetalloxidmasse
DE19638249 1996-09-19
PCT/EP1997/004903 WO1998012167A1 (fr) 1996-09-19 1997-09-09 Procede pour la fabrication d'une matiere a action catalytique constituee d'oxydes de plusieurs metaux

Publications (1)

Publication Number Publication Date
EP0931048A1 true EP0931048A1 (fr) 1999-07-28

Family

ID=7806137

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97942001A Ceased EP0931048A1 (fr) 1996-09-19 1997-09-09 Procede pour la fabrication d'une matiere a action catalytique constituee d'oxydes de plusieurs metaux

Country Status (6)

Country Link
EP (1) EP0931048A1 (fr)
JP (1) JP2001500427A (fr)
AU (1) AU4383597A (fr)
DE (1) DE19638249A1 (fr)
ID (1) ID18317A (fr)
WO (1) WO1998012167A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4182237B2 (ja) * 1997-09-30 2008-11-19 住友化学株式会社 イソブタンの気相接触酸化反応用触媒およびこれを用いてなるアルケンおよび／または含酸素化合物の製造方法
US6017846A (en) * 1999-01-11 2000-01-25 Saudi Basic Industries Corporation Highly active and selective catalysts for the production of unsaturated nitriles, methods of making and using the same
JP3744751B2 (ja) * 1999-12-08 2006-02-15 株式会社日本触媒 担体、複合酸化物触媒、およびアクリル酸の製造方法
DE10046957A1 (de) * 2000-09-21 2002-04-11 Basf Ag Verfahren zur Herstellung eines Multimetalloxid-Katalysators, Verfahren zur Herstellung ungesättigter Aldehyde und/oder Carbonsäuren und Bandcalziniervorrichtung
JP4442317B2 (ja) * 2004-05-21 2010-03-31 三菱化学株式会社 複合酸化物触媒の製造方法
JP4858266B2 (ja) * 2007-03-28 2012-01-18 三菱化学株式会社 複合酸化物触媒の製造法
US9643171B2 (en) * 2010-02-25 2017-05-09 Saudi Basic Industries Corporation Method of making heteropoly acid compound catalysts

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1199905A (fr) * 1982-06-07 1986-01-28 William J. Kennelly Agents de catalyse, et leur emploi pour la preparation d'acides carboxyliques insatures
JPH047037A (ja) * 1990-04-23 1992-01-10 Mitsubishi Rayon Co Ltd メタクリル酸製造用触媒の調製法
DE4022212A1 (de) * 1990-07-12 1992-01-16 Basf Ag Massen der allgemeinen formel mo(pfeil abwaerts)1(pfeil abwaerts)(pfeil abwaerts)2(pfeil abwaerts)(pfeil hoch)p(pfeil hoch)(pfeil abwaerts)a(pfeil abwaerts)(pfeil hoch)v(pfeil hoch)(pfeil abwaerts)b(pfeil abwaerts)(pfeil hoch)x(pfeil hoch)(pfeil hoch)1(pfeil hoch)(pfeil abwaerts)c(pfeil abwaerts)(pfeil hoch)x(pfeil hoch)(pfeil hoch)2(pfeil hoch)(pfeil abwaerts)d(pfeil abwaerts)(pfeil hoch)x(pfeil hoch)(pfeil hoch)3(pfeil hoch)(pfeil abwaerts)e(pfeil abwaerts)(pfeil hoch)s(pfeil hoch)(pfeil hoch)b(pfeil hoch)(pfeil abwaerts)f(pfeil abwaerts)(pfeil hoch)r(pfeil hoch)(pfeil hoch)e(pfeil hoch)(pfeil abwaerts)g(pfeil abwaerts)(pfeil hoch)s(pfeil hoch)(pfeil abwaerts)h(pfeil abwaerts)(pfeil hoch)o(pfeil hoch)(pfeil abwaerts)n(pfeil abwaerts)
JP2814317B2 (ja) * 1991-06-12 1998-10-22 三菱レイヨン株式会社 メタクリル酸製造用触媒の調製法
DE4329907A1 (de) * 1993-09-04 1995-03-09 Basf Ag Multimetalloxidmassen, die wenigstens die Elemente Antimon und Phosphor sowie zusätzlich wenigstens eines der beiden Elemente Mo, W enthalten

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9812167A1 *

Also Published As

Publication number Publication date
ID18317A (id) 1998-03-26
AU4383597A (en) 1998-04-14
DE19638249A1 (de) 1998-03-26
JP2001500427A (ja) 2001-01-16
WO1998012167A1 (fr) 1998-03-26

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