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WO2003078369A1 - Oxydation de o-xylol en acide o-tolyle et en autres produits d'oxydation par apport progressif d'un gaz contenant de l'oxygene - Google Patents

Oxydation de o-xylol en acide o-tolyle et en autres produits d'oxydation par apport progressif d'un gaz contenant de l'oxygene Download PDF

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Publication number
WO2003078369A1
WO2003078369A1 PCT/EP2003/002813 EP0302813W WO03078369A1 WO 2003078369 A1 WO2003078369 A1 WO 2003078369A1 EP 0302813 W EP0302813 W EP 0302813W WO 03078369 A1 WO03078369 A1 WO 03078369A1
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WO
WIPO (PCT)
Prior art keywords
oxygen
xylene
oxidation
liquid
reaction
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
PCT/EP2003/002813
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German (de)
English (en)
Inventor
Andreas Brodhagen
Beatrice RÖßLER
Thomas RÜHL
Hans-Josef Wolf
Frank Rosowski
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
Priority to AU2003219077A priority Critical patent/AU2003219077A1/en
Publication of WO2003078369A1 publication Critical patent/WO2003078369A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • 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
    • C07C45/27—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation
    • C07C45/32—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen
    • C07C45/33—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties
    • C07C45/34—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds
    • C07C45/36—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds in compounds containing six-membered aromatic rings
    • 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
    • C07C29/48—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by oxidation reactions with formation of hydroxy groups
    • C07C29/50—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by oxidation reactions with formation of hydroxy groups with molecular oxygen only
    • 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

Definitions

  • the present invention relates to a process for the preparation of oxidation products of o-xylene which can be further oxidized to phthalic anhydride by oxidation of o-xylene in the liquid phase.
  • Phthalic anhydride is one of the technically most important aromatic compounds. It is e.g. B. used in the synthesis of alkyd resins, unsaturated polyester resins, paints, plastics, plasticizers, phthalocyanine dyes, insect repellents, denaturing agents and for the production of numerous fine chemicals.
  • Phthalic anhydride is produced industrially by the oxidation of o-xylene or naphthalene. Two oxidation processes are common. On the one hand, the oxidation in the gas phase is carried out on a heterogeneous catalyst, generally a vanadium-containing catalyst. In this process, however, about 20 mol% of the starting material is converted to CO x and is therefore lost as a yield.
  • DE 100 02 807 and DE 100 02 810 also relate to processes for the oxidation of o-xylene with oxygen.
  • the two-stage reaction of the oxidation of o-xylene to phthalic anhydride generally has a better selectivity than the one-stage oxidation in the gas phase. Nevertheless, there is also a risk of over-oxidation of the o-xylene in the liquid phase oxidation with the formation of CO x , acetic acid, formic acid or other products which arise from the loss of one or more carbon atoms from the o-xylene and can no longer be converted into phthalic anhydride by further oxidation ,
  • the invention is therefore based on the object of specifying a process for the liquid phase oxidation of o-xylene which leads as selectively as possible to those oxidation products which can be further oxidized to phthalic anhydride.
  • this object is achieved by a process in which an o-xylene-containing liquid stream is passed through at least one reaction zone and an oxygen-containing gas is bubbled into the liquid stream at at least two points spaced apart in the direction of flow of the liquid stream.
  • the oxygen-containing gas usually contains one or more inert gases, such as, for. B. nitrogen, argon or carbon dioxide.
  • the oxygen volume fraction of the oxygen-containing gas is preferably 10 to 90% by volume, preferably 15 to 35% by volume; the rest is made up of inert gas.
  • the use of air as an oxygen-containing gas is particularly preferred.
  • the oxygen-containing gas is preferably bubbled in under conditions which allow intimate mixing of the gas and liquid phases.
  • those oxidation products of o-xylene which can be further oxidized to phthalic anhydride are obtained with high selectivity, in particular o-tolylic acid, methylbenzaldehyde, methylbenzyl alcohol, phthalide, di (methylbenzyl) phthalate, methylbenzylmethylbenzoate, mono (methylbenzyl) phthalate, methylbenzylformylbenzoate, formylbenzylmethylbenzoate, monomethylphthalate, methylbenzyl formate and methylbenzyl acetate, of which o-tolylic acid forms the main part.
  • selectivity of the oxidation reaction is addressed in the following, the selectivity is meant with reference to the sum of the above-mentioned compounds.
  • the oxygen-containing gas is supplied in a manner which largely avoids local oxygen concentration maxima.
  • the bubbled-in oxygen-containing gas reacts with xylene while consuming oxygen, the dispersed gas phase becoming depleted of oxygen.
  • the bubbled-in oxygen-containing gas can coalesce with the dispersed low-oxygen gas phase to form gas bubbles with an average oxygen content.
  • the oxygen content of the gas phase should not drop below a critical value. This is preferably achieved by monitoring the oxygen volume fraction of the exhaust gas.
  • the oxygen volume fraction of the oxygen-depleted gas is preferably 0.01 to 7.5% by volume, in particular 0.05 to 6% by volume, particularly preferably 1 to 6% by volume.
  • Any reaction apparatus in which a gas phase is dispersed into a liquid phase by suitable organs, such as gas distributors or nozzles, is suitable for carrying out the process according to the invention. Suitable examples of this are stirred tank reactors and bubble columns.
  • baffles are provided in the reaction zone which extend essentially in a plane perpendicular to the direction of flow of the liquid stream and are spaced apart from one another.
  • the internals divide the reaction zone into individual chambers, which the liquid stream passes through in succession.
  • the internals prevent backmixing in the direction of flow.
  • the oxygen-containing gas is preferably bubbled in at least at one point between two successive internals.
  • the reaction zone is preferably elongated and in particular has a ratio of length to diameter of more than 5, in particular more than 10.
  • the number of sections separated from one another by internals can, for. B. 2 to 15 or 5 to 10. Suitable internals such. B. perforated plates or valve bottoms.
  • reaction zones or the sections of a reaction zone which are separated from one another by internals are advantageously provided with a packed bed, at least in partial areas.
  • the packed bed causes (re) dispersion of the gas phase and good mixing transversely to the direction of flow.
  • the oxidation of the o-xylene is exothermic.
  • the heat of reaction is preferably removed.
  • heat exchangers which are arranged in the reaction zones or are attached to the outer reactor jacket or are therefore in a heat-conducting connection and through which a suitable cooling medium flows can be provided. So it is z. B. possible to provide cooling coils or cooling fingers arranged in the reaction zones.
  • a preferred way of dissipating the heat of reaction is to cool the recycle stream by z. B. conducts through a heat exchanger.
  • different types of heat dissipation can be combined.
  • the pressure is preferably 10 to 30 bar, in particular 15 to 25 bar. If several reaction zones connected in series are used, the pressure in the individual reaction zones is preferably essentially the same (apart from a small pressure difference which is necessary for the transport of the mixture of liquid Stream and dispersed gas phase from one reaction zone to the next is required).
  • the reaction temperature is preferably 120 to 210 ° C, in particular 138 to 180 ° C, particularly preferably 140 to 165 ° C.
  • the residence time of the liquid stream in the reaction zone or the accumulated residence time in the reaction zones when using reaction zones connected in series is preferably 0.5 to 4.5 hours.
  • the process according to the invention is preferably carried out in the presence of a transition metal-containing catalyst.
  • Suitable catalysts are, on the one hand, transition metal salts or complexes soluble in o-xylene, such as, in particular, cobalt and / or manganese salts or complexes.
  • Cobalt salts of aliphatic, alicyclic or aromatic carboxylic acids are preferred. Examples include naphthenates, acetates, propionates, butanoates, pentanoates, hexanoates, heptanoates, octanoates, 2-ethylhexanoates, nonanoates, isononanoates, decanoates, laurinoates, palmitates, stearates, benzoates, tolylates, phthalates and citrates.
  • a suitable catalyst is e.g. B. Cobalt naphtenate.
  • the catalyst which is suitably metered in in the form of a catalyst stock solution is preferably added to the feed containing o-xylene outside the reaction zone. This avoids the coincidence of locally high catalyst concentrations with the reactants o-xylene and oxygen, which could otherwise lead to undesired overoxidation.
  • the catalyst is used in an amount of 2 to 500 ppm, preferably 5 to 50 ppm, calculated as metal, based on the feed containing o-xylene. Higher catalyst concentrations can lead to undesirable precipitation in the reactor.
  • heterogeneous catalysts i.e. unsuitable or hardly soluble transition metal salts or complexes in the liquid stream. They can be in the form of a suspension in the liquid stream or can be arranged firmly in the reaction zones, for. B. as a bed or coating of the inner walls.
  • a heterogeneous catalyst z. B. Cobalt (II) oxalate is suitable.
  • the reaction discharge is suitably fed from a gas-liquid separator in which the liquid reaction mixture and the oxygen-depleted gas are separated from one another.
  • a gas-liquid separator for. B. a gravity separator, ie a vessel with a low flow velocity, in which the gas phase and the liquid phase due to their different Separate density from each other, suitable.
  • a swirl separator ie a cylindrical container, into which the mixed-phase reaction discharge is introduced tangentially to the container wall can be used.
  • the separated liquid reaction mixture is at least partially returned to the reaction zone.
  • the recycling of part of the liquid reaction mixture allows a sufficiently large liquid volume flow to be maintained in the reaction zones.
  • a fresh o-xylene-containing feed is preferably fed into the reaction zone.
  • the ratio of feed to recycled liquid reaction mixture is generally 1:10 to 1: 200, preferably 1:50 to 1: 100.
  • a quantity of the liquid reaction mixture discharged from the reaction zone is expediently discharged as a product stream.
  • oxidation products of o-xylene in particular o-tolylic acid, methylbenzaldehyde, methylbenzyl alcohol, phthalide, methylbenzylmethylbenzoate and monomethylbenzyl phthalate, can be isolated from the product stream by customary processes, in particular by distillation.
  • the separated, unreacted o-xylene is expediently returned to the oxidation reaction.
  • the oxidation products separated off are evaporated and, in a second step, oxidized to phthalic anhydride in the gas phase in the gas phase in the presence of an oxygen-containing gas.
  • One is generally used to carry out the second stage
  • Suitable catalysts are those with an active mass of titanium dioxide in the form of its anatase modification and / or vanadium pentoxide.
  • Fig. 1 shows a schematic representation of a device suitable for carrying out the method according to the invention with a reaction zone divided by internals.
  • o-xylene 3 is premixed with a catalyst stock solution 2 and the o-xylene-containing feed is fed to reactor 1.
  • the reactor 1 is divided into chambers by perforated plates 10a-d arranged transversely to the direction of flow. Via the lines 4a-4e, an oxygen-containing gas, eg. B. air introduced.
  • an oxygen-containing gas eg. B. air introduced.
  • the reaction discharge is fed to the gas-liquid separator 6.
  • the liquid phase is cooled in the heat exchanger 8 and fed to the pump 9.
  • a partial stream of the liquid reaction mixture is discharged via line 5.
  • the oxidation products of o-xylene formed are isolated therefrom by methods known per se.
  • the other partial stream of the liquid reaction mixture is introduced again into the reactor 1 via line 11.
  • o-xylene 3 is premixed with a catalyst stock solution 2 and the o-xylene-containing feed is fed to the reactor la.
  • the discharge from the reactor la is fed to the reactor 1b via line 12 without phase separation.
  • an oxygen-containing gas, for. B. air introduced.
  • the reaction discharge is fed to the gas-liquid separator 6.
  • the liquid phase is cooled in the heat exchanger 8 and fed to the pump 9.
  • a partial stream of the liquid reaction mixture is discharged via line 5. From this, the oxidation products of o-xylene formed are isolated by methods known per se.
  • the other partial stream of the liquid reaction mixture is introduced again into the reactor la via line 11.
  • the two reactors are vertically arranged high-pressure reaction tubes with a length of 2 m and a diameter of 30 mm.
  • a metering point for air was arranged near the lower end of the reaction tubes.
  • a continuous liquid oxidation of o-xylene was carried out at a pressure of 20 bar.
  • the supplied o-xylene was mixed with cobalt naphtenate before being introduced into the first reactor.
  • An amount of the reaction mixture corresponding to the o-xylene fed was continuously discharged from the second reactor.
  • the composition of the oxidation products was analyzed by high performance liquid chromatography. The operating parameters and analysis results are summarized in the following table.
  • Example 3 (comparison)
  • a device was used as in the previous examples, but comprising only one reactor.

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

Abstract

L'invention concerne un procédé permettant de produire des produits d'oxydation de o-xylol, dont l'oxydation peut être poursuivie pour former de l'acide phtalique. Selon ledit procédé, un flux liquide contenant du o-xyolol est guidé à travers au moins une zone de réaction et un gaz contenant de l'oxygène est introduit sous forme effervescente par tourbillonnement en au moins deux points à distance mutuelle, dans le sens d'écoulement du flux liquide.
PCT/EP2003/002813 2002-03-18 2003-03-18 Oxydation de o-xylol en acide o-tolyle et en autres produits d'oxydation par apport progressif d'un gaz contenant de l'oxygene Ceased WO2003078369A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003219077A AU2003219077A1 (en) 2002-03-18 2003-03-18 Oxidation of o-xylol to form o-toluic acid and other oxidation products by the staggered supply of an oxygen-containing gas

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10211907.4 2002-03-18
DE2002111907 DE10211907A1 (de) 2002-03-18 2002-03-18 Oxidation von o-Xylol zu o-Tolylsäure und anderen Oxidationsprodukten durch gestaffelte Zufuhr eines sauerstoffhaltigen Gases

Publications (1)

Publication Number Publication Date
WO2003078369A1 true WO2003078369A1 (fr) 2003-09-25

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Application Number Title Priority Date Filing Date
PCT/EP2003/002813 Ceased WO2003078369A1 (fr) 2002-03-18 2003-03-18 Oxydation de o-xylol en acide o-tolyle et en autres produits d'oxydation par apport progressif d'un gaz contenant de l'oxygene

Country Status (3)

Country Link
AU (1) AU2003219077A1 (fr)
DE (1) DE10211907A1 (fr)
WO (1) WO2003078369A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102701940A (zh) * 2004-09-02 2012-10-03 奇派特石化有限公司 优化的液相氧化

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US7399882B2 (en) 2004-09-02 2008-07-15 Eastman Chemical Company Optimized liquid-phase oxidation
US7495125B2 (en) 2004-09-02 2009-02-24 Eastman Chemical Company Optimized liquid-phase oxidation
US7361784B2 (en) 2004-09-02 2008-04-22 Eastman Chemical Company Optimized liquid-phase oxidation
US7589231B2 (en) 2004-09-02 2009-09-15 Eastman Chemical Company Optimized liquid-phase oxidation
US7568361B2 (en) 2004-09-02 2009-08-04 Eastman Chemical Company Optimized liquid-phase oxidation
US7741515B2 (en) 2004-09-02 2010-06-22 Eastman Chemical Company Optimized liquid-phase oxidation
US7582793B2 (en) 2004-09-02 2009-09-01 Eastman Chemical Company Optimized liquid-phase oxidation
US7390921B2 (en) 2004-09-02 2008-06-24 Eastman Chemical Company Optimized liquid-phase oxidation
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US7507857B2 (en) 2004-09-02 2009-03-24 Eastman Chemical Company Optimized liquid-phase oxidation
US7692037B2 (en) 2004-09-02 2010-04-06 Eastman Chemical Company Optimized liquid-phase oxidation
US7572936B2 (en) 2004-09-02 2009-08-11 Eastman Chemical Company Optimized liquid-phase oxidation
US7504535B2 (en) 2004-09-02 2009-03-17 Eastman Chemical Company Optimized liquid-phase oxidation
US7572932B2 (en) 2004-09-02 2009-08-11 Eastman Chemical Company Optimized liquid-phase oxidation
US7563926B2 (en) 2004-09-02 2009-07-21 Eastman Chemical Company Optimized liquid-phase oxidation
US7482482B2 (en) 2004-09-02 2009-01-27 Eastman Chemical Company Optimized liquid-phase oxidation
US7608732B2 (en) 2005-03-08 2009-10-27 Eastman Chemical Company Optimized liquid-phase oxidation
US7683210B2 (en) 2004-09-02 2010-03-23 Eastman Chemical Company Optimized liquid-phase oxidation
US7371894B2 (en) 2004-09-02 2008-05-13 Eastman Chemical Company Optimized liquid-phase oxidation
US7910769B2 (en) 2004-09-02 2011-03-22 Eastman Chemical Company Optimized liquid-phase oxidation
RU2384563C2 (ru) * 2004-09-02 2010-03-20 Истман Кемикал Компани Оптимизированное жидкофазное окисление
US7586000B2 (en) 2004-09-02 2009-09-08 Eastman Chemical Company Optimized liquid-phase oxidation
US7608733B2 (en) 2004-09-02 2009-10-27 Eastman Chemical Company Optimized liquid-phase oxidation
US7692036B2 (en) 2004-11-29 2010-04-06 Eastman Chemical Company Optimized liquid-phase oxidation
US7884232B2 (en) 2005-06-16 2011-02-08 Eastman Chemical Company Optimized liquid-phase oxidation
US7355068B2 (en) 2006-01-04 2008-04-08 Eastman Chemical Company Oxidation system with internal secondary reactor
US7358389B2 (en) 2006-01-04 2008-04-15 Eastman Chemical Company Oxidation system employing internal structure for enhanced hydrodynamics

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1091568B (de) * 1957-08-02 1960-10-27 Bergwerksgesellschaft Hibernia Verfahren und Vorrichtung zur kontinuierlichen Durchfuehrung von Reaktionen zwischen Gasen und Fluessigkeiten
DE1287575B (de) * 1964-02-03 1969-01-23 Du Pont Verfahren zur Herstellung von im wesentlichen aus Cyclohexanol und Cyclohexanon bestehenden Teiloxydationsprodukten des Cyclohexans
EP0135718A1 (fr) * 1983-08-10 1985-04-03 BASF Aktiengesellschaft Procédé pour la préparation en continu de composés contenant de l'oxygène
EP0256352A1 (fr) * 1986-08-14 1988-02-24 Sisas Societa'italiana Serie Acetica E Sintetica Spa Procédé de préparation de l'anhydride phtalique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1091568B (de) * 1957-08-02 1960-10-27 Bergwerksgesellschaft Hibernia Verfahren und Vorrichtung zur kontinuierlichen Durchfuehrung von Reaktionen zwischen Gasen und Fluessigkeiten
DE1287575B (de) * 1964-02-03 1969-01-23 Du Pont Verfahren zur Herstellung von im wesentlichen aus Cyclohexanol und Cyclohexanon bestehenden Teiloxydationsprodukten des Cyclohexans
EP0135718A1 (fr) * 1983-08-10 1985-04-03 BASF Aktiengesellschaft Procédé pour la préparation en continu de composés contenant de l'oxygène
EP0256352A1 (fr) * 1986-08-14 1988-02-24 Sisas Societa'italiana Serie Acetica E Sintetica Spa Procédé de préparation de l'anhydride phtalique

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102701940A (zh) * 2004-09-02 2012-10-03 奇派特石化有限公司 优化的液相氧化
CN101693655B (zh) * 2004-09-02 2014-01-08 奇派特石化有限公司 优化的液相氧化方法

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Publication number Publication date
DE10211907A1 (de) 2003-10-02
AU2003219077A1 (en) 2003-09-29

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