WO1996025391A1 - Reduction d'ammoniac residuel produit dans le cadre de procedes d'ammoxydation - Google Patents

Reduction d'ammoniac residuel produit dans le cadre de procedes d'ammoxydation Download PDF

Info

Publication number
WO1996025391A1
WO1996025391A1 PCT/US1996/002206 US9602206W WO9625391A1 WO 1996025391 A1 WO1996025391 A1 WO 1996025391A1 US 9602206 W US9602206 W US 9602206W WO 9625391 A1 WO9625391 A1 WO 9625391A1
Authority
WO
WIPO (PCT)
Prior art keywords
methanol
reactor
ammonia
mole percent
catalyst
Prior art date
Application number
PCT/US1996/002206
Other languages
English (en)
Inventor
John Ferrell Braun
Robert Thomas Nowak
Charles Wendell Rooks
Daniel Eric Steinmeyer
Original Assignee
Monsanto Company
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 Monsanto Company filed Critical Monsanto Company
Priority to AU48692/96A priority Critical patent/AU4869296A/en
Publication of WO1996025391A1 publication Critical patent/WO1996025391A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C253/00—Preparation of carboxylic acid nitriles
    • C07C253/24—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons
    • C07C253/26—Preparation of carboxylic acid nitriles by ammoxidation of hydrocarbons or substituted hydrocarbons containing carbon-to-carbon multiple bonds, e.g. unsaturated aldehydes

Definitions

  • the invention relates to reduction of ammonia wastes produced in processes for production of
  • the invention is based on the discovery that in a process for making acrylonitrile by passing propylene, oxygen (air), and ammonia through a
  • the amount of ammonia contained in the product stream can be any suitable fluidized bed of aimoxidation catalyst
  • methanol is introduced into a fluidized bed reaction system in which a bed of ammoxidation catalyst is fluidized by a flow of the reactants, propylene, ammonia, and oxygen containing gas (air).
  • a bed of ammoxidation catalyst is fluidized by a flow of the reactants, propylene, ammonia, and oxygen containing gas (air).
  • oxygen containing gas air
  • any of the numerous catalysts known for the airmoxidation of propylene can be employed using conventional ammoxidation reaction conditions.
  • catalysts mainly consisting of bismuth phosphates or molybdates or of antimony and uranium oxides or of bismuth phosphates or molybdates doped with iron, nickel, cobalt etc., or of antimony oxide and oxides of metals such as iron, cobalt, or nickel may be used.
  • a particularly preferred catalyst is represented by the formula Sb a U b Fe c Bi d MO e Me f O g in which Me is nickel or cobalt, a is 1 to 10, b is 0.1 to 5, c is 0.1 to 5, d is 0.001 to 0.1, e is 0.001 to .1, f is 0 to 0.1 and g is a number taken to satisfy the valences of the quantities of other components present.
  • the methanol will be introduced at a point and in an amount such that the ammonia content of the reactor effluent will be less than 0.5 mole percent and lower than if no methanol were introduced and such that acrylonitrile production measured as weight per unit of time is at least 97% by weight of what would be
  • ammonia effluent will be less than 0.25 mole percent or, most preferably, substantially eliminated with less than 1% reduction in acrylonitrile production.
  • the methanol is introduced into the fluidized bed reactor at a point where 5% to 60% by weight of the catalyst in the reactor is above the methanol
  • the weight of the catalyst above the injection point refers to the weight when the bed is fluidized under operating conditions. Also, it is contemplated that the catalyst charge will be an amount chosen to ensure complete ammoxidation of the propylene but without undue excess.
  • the optimum point of introduction may vary depending on how much excess catalyst, if any, is present; catalyst activity; surface area; etc. For any system, the optimum
  • injection point can be determined by routine testing conducted in light of the disclosure herein.
  • the amount of methanol used will be sufficient to react with a major portion of the ammonia not reacted with propylene. However it is desirable to avoid excesses of methanol which would be expensive to separate from the acrylonitrile product.
  • the methanol content of the effluent will be less than 0.25 mole percent, most preferably, less than 0.01 mole percent. Generally, the use of from 0.8 to 2.0 times the moles stoichiometrically required to react with the ammonia in excess of that required for the ammoxidation of propylene will give satisfactory results.
  • the amount of methanol to be utilized will depend upon the catalyst in use and the amount present; the quantities of other reactants present; and flow rates in the fluidized bed system. It is
  • the methanol in a downward direction so that the openings through which it is introduced will not become clogged when the reactor is shut down or methanol flow is stopped for maintenance or other reasons.
  • methanol introduction means will generally be of relatively small dimensions and, more importantly, may not be operated continuously, care should be taken to prevent blockage. It is
  • a gas flow in addition to methanol be maintained at all times that a catalyst charge is present on the reactor, even if the reactor bed is not fluidized.
  • the gas can be any inert gas which is defined as a gas which will not adversely affect the reaction or reactor materials of
  • nitrogen or carbon dioxide can generally be used at any time.
  • Air can be used in amounts which will not form explosive mixtures with methanol (or in any amount if the reactor is "down” or if methanol is not being introduced into the reaction).
  • Steam can be conveniently and advantageously used if the reaction is in progress.
  • Mixtures of gases can be used.
  • the gas flow linear velocity through the orifices of the methanol introduction means should exceed (preferably by ten to fifty times) the linear velocity of other gases through the fluid bed reactor. If the reactor is "down” and no gas flow, for example, from purges of the reactant inlets, is present, it is still desirable to maintain a minimal flow to ensure catalyst fines are not drawn into the methanol
  • the openings in the sparger, tube, or other means through which methanol is introduced be significantly larger than the catalyst particles present in the reactor. More specifically, the diameters of the openings (or smallest dimension of the opening if non-round openings are used) should be at least ten, preferably, at least twenty or thirty times the mean particle size of the largest 10% by weight of the catalyst particles. There is no upper limit on opening size except such as may be dictated by considerations of gas flow patterns and rates which may also render it desirable to decrease the number of openings as opening size increases.
  • the oxygen (air) should be sufficient to prevent catalyst reduction but not so great as to form explosive mixtures.
  • a 4.1 cm inside diameter by 1.8 meter high fluidized bed reactor constructed of 316 stainless steel is used.
  • the outlet end of the reactor is connected to a gas chromatograph for
  • Propylene, ammonia and air feeds are supplied via mass flow controllers and are premixed before being brought into contact with the fluidized bed.
  • the methanol is fed separately by a positive displacement pump and is vaporized by heating prior to being introduced into the reactor.
  • the reactor contains the amount shown in Table 1 below of catalyst indicated. Catalyst number 1 has the
  • Catalyst 2 is a mixture of iron and antimony oxides deposited on a silica carrier.
  • Catalyst 3 is a mixture of bismuth, molybdenum, and iron oxides on a silica carrier.
  • each example compares a limited number of successive runs with methanol in the feed stream against a control in which no methanol is introduced.
  • an inert gas flow through the methanol sparger openings (which are about thirty times the diameter of the mean particle size of the largest 10% by weight of the catalyst particles) at a linear velocity about 30 times greater than the linear

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

On réduit les effluents d'ammoniac provenant de procédés à lit fluidisé destinés à l'ammoxydation catalytique de propylène pour former de l'acrylnitrile en introduisant du méthanol dans le lit fluidisé au niveau d'emplacements choisis.
PCT/US1996/002206 1995-02-17 1996-02-16 Reduction d'ammoniac residuel produit dans le cadre de procedes d'ammoxydation WO1996025391A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU48692/96A AU4869296A (en) 1995-02-17 1996-02-16 Reduction of ammonia wastes associated with ammoxidation processes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US39072695A 1995-02-17 1995-02-17
US08/390,726 1995-02-17

Publications (1)

Publication Number Publication Date
WO1996025391A1 true WO1996025391A1 (fr) 1996-08-22

Family

ID=23543674

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1996/002206 WO1996025391A1 (fr) 1995-02-17 1996-02-16 Reduction d'ammoniac residuel produit dans le cadre de procedes d'ammoxydation

Country Status (2)

Country Link
AU (1) AU4869296A (fr)
WO (1) WO1996025391A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1086152C (zh) * 1997-09-03 2002-06-12 中国石油化工总公司 烯烃氨氧化生产丙烯腈催化剂
US6716405B1 (en) 1997-06-06 2004-04-06 China Petro-Chemical Corporation Process for removing unreacted ammonia from an effluent in a hydrocarbon ammoxidation reaction

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3911089A (en) * 1972-10-06 1975-10-07 Sumitomo Chemical Co Process for preparing hydrogen cyanide
US5288473A (en) * 1992-10-09 1994-02-22 The Standard Oil Company Process for elimination of waste material during manufacture of acrylonitrile
EP0638546A1 (fr) * 1993-08-11 1995-02-15 The Standard Oil Company Procédé servant à reduire des déchets pendant la préparation d'acrylonitrile

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3911089A (en) * 1972-10-06 1975-10-07 Sumitomo Chemical Co Process for preparing hydrogen cyanide
US5288473A (en) * 1992-10-09 1994-02-22 The Standard Oil Company Process for elimination of waste material during manufacture of acrylonitrile
EP0638546A1 (fr) * 1993-08-11 1995-02-15 The Standard Oil Company Procédé servant à reduire des déchets pendant la préparation d'acrylonitrile

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6716405B1 (en) 1997-06-06 2004-04-06 China Petro-Chemical Corporation Process for removing unreacted ammonia from an effluent in a hydrocarbon ammoxidation reaction
CN1086152C (zh) * 1997-09-03 2002-06-12 中国石油化工总公司 烯烃氨氧化生产丙烯腈催化剂

Also Published As

Publication number Publication date
AU4869296A (en) 1996-09-04

Similar Documents

Publication Publication Date Title
EP1284815B1 (fr) Dispositif d'adjonction controlee optimisee de reactifs dans des reacteurs en continu et procedes d'utilisation
US5288473A (en) Process for elimination of waste material during manufacture of acrylonitrile
KR970007913B1 (en) High productivity process for the production of maleic anhydride
US5871705A (en) Process for producing trichlorosilane
US5492649A (en) Process for soot-free preparation of hydrogen and carbon monoxide containing synthesis gas
EP0320904B1 (fr) Procédé de préparation d'acrylonitrile
US5457223A (en) Process for elimination of waste material during manufacture of acrylonitrile
US3528930A (en) Production of synthesis gas
EP0832877B1 (fr) Procédé d'ammoxydation dans un réacteur à lit fluidisé
US4631182A (en) Process for preparation of a reducing gas
US5914424A (en) Process for producing acrylonitrile
EP0089118B1 (fr) Procédé pour la production d'acide cyanhydrique
CN101171214B (zh) 苯乙烯的制造方法
EP0696579B1 (fr) Procédé de réduction des déchets produits lors de la production d'acrylonitrile
US5965765A (en) Process for producing α,β-unsaturated nitrile
WO1996025391A1 (fr) Reduction d'ammoniac residuel produit dans le cadre de procedes d'ammoxydation
JP3091168B2 (ja) 流動層反応器におけるアンモ酸化法
CA1106573A (fr) Appareillage et procede d'obtention de chlore et d'oxyde de fer a partir de chlorure ferrique
CN100415751C (zh) 制造异氰酸酯基有机硅烷的方法
KR19980703649A (ko) α,β-불포화 니트릴의 제조 방법
EP0034442A2 (fr) Procédé de préparation d'aldéhydes et d'acides non saturés
JPH03246269A (ja) アセトニトリルの増収方法
JP4573970B2 (ja) アクリロニトリルの製造方法
JP3974951B2 (ja) α，β−不飽和ニトリルの製造方法
CN220610404U (zh) 制备异氰酸酯的反应器

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AU AZ BB BG BR BY CA CN CZ EE FI GE HU IS JP KG KR KZ LK LR LT LV MD MG MK MN MX NO NZ PL RO RU SG SI SK TJ TM TR TT UA US UZ VN AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase