WO2006082215A2 - Systeme catalytique pour reactions catalytiques en phase gazeuse a activite catalytique croissante dans le sens d'ecoulement du gaz - Google Patents

Systeme catalytique pour reactions catalytiques en phase gazeuse a activite catalytique croissante dans le sens d'ecoulement du gaz Download PDF

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Publication number
WO2006082215A2
WO2006082215A2 PCT/EP2006/050616 EP2006050616W WO2006082215A2 WO 2006082215 A2 WO2006082215 A2 WO 2006082215A2 EP 2006050616 W EP2006050616 W EP 2006050616W WO 2006082215 A2 WO2006082215 A2 WO 2006082215A2
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WO
WIPO (PCT)
Prior art keywords
catalyst
catalyst system
gas phase
activity
gas
Prior art date
Application number
PCT/EP2006/050616
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German (de)
English (en)
Other versions
WO2006082215A3 (fr
Inventor
Ruprecht Meissner
Hans-Martin Allmann
Michael Hesse
Jürgen ZÜHLKE
Original Assignee
Basf Aktiengesellschaft
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Publication of WO2006082215A2 publication Critical patent/WO2006082215A2/fr
Publication of WO2006082215A3 publication Critical patent/WO2006082215A3/fr

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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
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • 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
    • B01J35/19—Catalysts containing parts with different compositions
    • 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
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/0015—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor
    • B01J8/003—Feeding of the particles in the reactor; Evacuation of the particles out of the reactor in a downward flow
    • 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
    • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
    • B01J8/02—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds
    • B01J8/06—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with stationary particles, e.g. in fixed beds in tube reactors; the solid particles being arranged in tubes
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
    • C07C17/15—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination
    • C07C17/152—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination of hydrocarbons
    • C07C17/156—Preparation of halogenated hydrocarbons by replacement by halogens with oxygen as auxiliary reagent, e.g. oxychlorination of hydrocarbons of unsaturated hydrocarbons
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/002—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by dehydrogenation
    • 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
    • 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
    • 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
    • C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
    • C07C51/265—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting having alkyl side chains which are oxidised to carboxyl groups
    • 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
    • C07C51/31—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation of cyclic compounds with ring-splitting
    • C07C51/313—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation of cyclic compounds with ring-splitting with molecular oxygen
    • 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
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/00743—Feeding or discharging of solids
    • B01J2208/00752—Feeding
    • 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
    • B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
    • B01J2208/02—Processes carried out in the presence of solid particles; Reactors therefor with stationary particles
    • B01J2208/023—Details
    • B01J2208/024—Particulate material
    • B01J2208/025—Two or more types of catalyst
    • 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
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/04—Mixing

Definitions

  • the present invention relates to catalyst systems for catalytic gas phase reactions, characterized in that the catalyst activity increases in the direction of flow of the gas, wherein the catalyst activity is controlled by mixtures of low active and highly active catalysts.
  • the invention furthermore relates to processes for the preparation of phthalic anhydride, ethylene dichloride, cyclohexanone, acrylic acid and maleic anhydride, the starting materials being reacted in the said catalyst system.
  • a variety of catalytic gas phase reactions are carried out in a fixed bed reactor.
  • a mixture of a gas containing molecular oxygen and the starting material to be oxidized is passed through a plurality of tubes arranged in a reactor, in which there is a bed of at least one catalyst.
  • the tubes are surrounded by a heat transfer medium, for example a molten salt.
  • a heat transfer medium for example a molten salt.
  • DE-A 25 46268 two-layer catalyst system
  • DE-A 198 23 262 three-layer catalyst system
  • DE-A 103 23 818 discloses an increase in activity due to an increasing BET surface area of the titanium dioxide used.
  • Activity-structured catalyst beds are used not only in the preparation of carboxylic acids or carboxylic anhydrides, but also, for example, in the gas-phase oxychlorination of ethylene to ethylene dichloride or in the dehydrogenation of cyclohexanol to cyclohexanone (K. Weissermel, H. -J. Arpe, Industrielle Organische Chemie, VCH Verlag Weinheim).
  • the number of activity levels is limited by the expense of catalyst preparation and catalyst filling. Despite a multi-layered catalyst system, pronounced hot spots can still form, which have a negative effect on the yield and accelerate the aging of the catalyst.
  • the object was therefore to find a catalyst system whose activity increases in the direction of flow of the catalyst, without a variety of different types of catalysts must be used.
  • the object was to show a simplified activity-structured catalyst system that has a continuous increase in activity.
  • the object was to show catalyst systems that have longer lifetimes compared to the prior art.
  • the object was to provide processes for the preparation of phthalic anhydride, ethylene dichloride, cyclohexanone, maleic anhydride and acrylic acid, which have a higher yield compared to the prior art. It has surprisingly been found that a catalyst system whose catalyst activity increases in the direction of flow of the gas, wherein the catalyst activity is controlled by mixtures of low active and highly active catalysts, can be used advantageously for exothermic and endothermic gas phase reaction.
  • Two different catalysts are particularly preferably used for controlling the activity, one of which (catalyst A) having a low activity and the other (catalyst B) having a high activity.
  • the catalyst A is highly selective.
  • the catalyst B is advantageously highly active and optionally less selective.
  • the activity of the catalysts A and B is adjusted such that mainly the catalyst A is present at the gas inlet of the catalyst bed and the catalyst B mainly at the gas outlet.
  • the different activity of the catalysts A and B can be adjusted by all measures known to the person skilled in the art. For example, different activity can be obtained by a different active mass content, by a different component composition in the active composition, by a different content of inert substances or by a different surface of a catalyst component.
  • a zone of higher activity can be arranged at the gas inlet in front of the point of lowest catalyst activity in order to facilitate the initiation of the reaction.
  • the increase in activity in the catalyst bed is advantageously carried out continuously. Consequently, the catalyst system according to the invention is no longer divided into individual zones of different activity, but has a continuous transition from areas of lower activity to areas of higher activity.
  • This continuous increase in activity is achieved by a continuous increase in the mixing ratio of catalyst A: B from 1: 0 to 0: 1.
  • the exact mixing ratios must be adapted to the respective reaction and the associated temperature profile. This optimization can be carried out by a person skilled in the art without any further effort, for example on the basis of the temperature profiles, by-product spectra or the total combustion CO-CO 2 analysis.
  • the catalyst system according to the invention is advantageously in a fixed bed reactor, in particular in a tube bundle reactor.
  • Tube bundle reactors are at Performing gas phase reactions known.
  • Typical tube bundle reactors have up to 40,000 individual tubes, the individual tubes usually having a diameter of 1 to 10 cm.
  • the filling of the tubes can advantageously be carried out so that from two storage containers (i) containing catalyst A and (ii) containing catalyst B continuously flow catalysts into a mixing tank.
  • the way in which mixing ratio the catalysts A and B are used, d. H. in what speed / amount the catalysts A and B are supplied to the mixing tank is controlled in dependence on the filling level. For example, if the gas inlet side is filled, mainly the catalyst A is supplied to the mixing tank. In the middle region of the catalyst beds, the catalysts are approximately in the same ratio, i. the mixing tank is typically filled with equal parts of catalyst A and B. If, however, the gas outlet side is filled, mainly the catalyst B is supplied to the mixing tank.
  • the mixing container is advantageously not a reservoir, but from there the catalysts pass directly, as described for example in US-A 4,402,643 or in the German application with the application number 102004012754.9, via a conveyor trough with drain funnel into the tubes.
  • the catalyst system according to the invention is particularly advantageous for exothermic gas-phase reactions, in particular for the preparation of phthalic anhydride, ethylene dichloride, acrylic acid, maleic anhydride or cyclohexanone.
  • the catalyst system according to the invention can also be used advantageously for endothermic reactions.
  • the invention further relates to a process for the production of phthalic anhydride by gas phase oxidation of xylene, naphthalene or mixtures thereof, wherein xylene, naphthalene or mixtures thereof and a gas containing molecular oxygen are reacted in the catalyst system of the invention.
  • the invention further relates to a process for the production of ethylene dichloride by gas phase oxychlorination of ethylene wherein ethylene is reacted with hydrochloric acid and air or oxygen to produce ethylene dichloride in the catalyst system of the invention.
  • the invention further relates to a process for the preparation of cyclohexanone by gas-phase dehydrogenation of cyclohexanol, wherein cyclohexanol is converted to cyclohexanone and hydrogen in the catalyst system according to the invention.
  • the invention further relates to a process for the preparation of maleic anhydride by benzene, butane or butene oxidation, wherein benzene, butane or butene and air or oxygen are converted to maleic anhydride in the catalyst system of the invention.
  • the invention further relates to a process for the preparation of acrylic acid by gas phase oxidation of propene and steam or air to acrolein in a first catalyst system and the further oxidation of acrolein in a second catalyst system to acrylic acid, wherein the first or the second or both catalyst systems according to the invention are designed.
  • one of the two prior art reactors may be equipped.
  • the high costs incurred by the preparation of many different catalysts and by the complicated filling of the individual catalyst layers, can be saved.
  • the lifetime of the catalyst system according to the invention is extended in comparison to catalyst systems from the prior art, since the hot spot in the catalyst system of the invention is distributed more uniformly over the entire catalyst bed.
  • catalytic gas phase reactions at lower, i. catalyst-sparing reaction temperatures are carried out as in the prior art.
  • the ability to carry out catalytic gas phase reactions at low reaction temperatures also has the advantage that fewer by-products are formed. Consequently, the catalyst system according to the invention is more selective and has a higher yield than the catalyst systems of the prior art.
  • the increase in the charge of the reactant stream in the catalyst system according to the invention can be carried out more rapidly than, for example, in a 2-layer catalyst system from the prior art.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Materials Engineering (AREA)
  • Catalysts (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

L'invention concerne des systèmes catalytiques pour des réactions catalytiques en phase gazeuse. L'invention est caractérisée en ce que l'activité catalytique croît dans le sens d'écoulement du gaz, cette activité catalytique étant régulée par mélange de catalyseurs à faible activité et à forte activité. La présente invention porte également sur des procédés pour préparer de l'anhydride phtalique, du chlorure d'éthylène, du cyclohexanone, de l'anhydride de l'acide maléique et de l'acide acrylique.
PCT/EP2006/050616 2005-02-02 2006-02-02 Systeme catalytique pour reactions catalytiques en phase gazeuse a activite catalytique croissante dans le sens d'ecoulement du gaz WO2006082215A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102005004926.5 2005-02-02
DE102005004926A DE102005004926A1 (de) 2005-02-02 2005-02-02 Katalysatorsystem für katalytische Gasphasenreaktionen mit einer in Flussrichtung des Gases zunehmenden Katalysatoraktivität

Publications (2)

Publication Number Publication Date
WO2006082215A2 true WO2006082215A2 (fr) 2006-08-10
WO2006082215A3 WO2006082215A3 (fr) 2006-12-28

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WO (1) WO2006082215A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007116018A1 (fr) * 2006-04-12 2007-10-18 Basf Se Systeme catalytque pour la fabrication d'acides carboxyliques et/ou d'hydrures d'acides carboxyliques

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10334132A1 (de) 2003-07-25 2005-04-07 Basf Ag Silber, Vanadium und ein Promotormetall enthaltendes Multimetalloxid und dessen Verwendung
DE102020129303A1 (de) 2020-11-06 2022-05-12 Linde Gmbh Verfahren und Anlage zur Herstellung eines oder mehrerer Kohlenwasserstoffe

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0099431A1 (fr) * 1982-07-20 1984-02-01 Amoco Corporation Procédé de production d'anhydride maléique

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0099431A1 (fr) * 1982-07-20 1984-02-01 Amoco Corporation Procédé de production d'anhydride maléique

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007116018A1 (fr) * 2006-04-12 2007-10-18 Basf Se Systeme catalytque pour la fabrication d'acides carboxyliques et/ou d'hydrures d'acides carboxyliques

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WO2006082215A3 (fr) 2006-12-28
DE102005004926A1 (de) 2006-08-03

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