US3402184A - Process of aromatic hydrocarbon oxidation - Google Patents

Process of aromatic hydrocarbon oxidation Download PDF

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US3402184A
US3402184A US504833A US50483365A US3402184A US 3402184 A US3402184 A US 3402184A US 504833 A US504833 A US 504833A US 50483365 A US50483365 A US 50483365A US 3402184 A US3402184 A US 3402184A
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reactor
oxidation
reactors
xylene
acid
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US504833A
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Berthoux Jean
Gerbelot-Barrillon Claude
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Progil SARL
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Progil SARL
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    • 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
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/582—Recycling of unreacted starting or intermediate materials

Definitions

  • ABSTRACT OF THE DISCLOSURE A process is described for the continuous liquid phase counter-current oxidation of aromatic hydrocarbons containing oxidizable side chains, especially the oxidizing of xylenes to various phthalic acids and/0r anhydrides.
  • the process is carried out in a series of reactors in which the reaction fluids are maintained at approximately constant pressures and without condensation between reactors. Off gases are dehydrated by azeotropic distillation in such a manner that the dehydrating agent is recovered and unreacted aromatics and solvents are recovered in a dehydrated state suitable for recycling into the oxidation process. 7
  • the present invention relates to an improved process for liquid phase oxidation of aromatic hydrocarbons containing one or more aliphatic side chains.
  • ortho-xylene can be oxidized in the presence of an inert solvent.
  • This ortho-xylene oxidation reaction is usually. conducted using temperatures ranging from 100 to 200 C., and using atmospheric or higher pressures in an aromatic hydrocarbon solvent, such as benzene or an aromatic carboxylic acid such as benzoic acid, or in an aliphatic acid solvent such as acetic acid, propionic acid, etc.
  • This reaction has already been conducted either in a discontinuous manneror in a continuous one in a single reactor, or, preferably, in several reactors put in series.
  • This last kind of process is a countercurrent xylene oxidation process conducted in 2 or 3 reactors maintained at pressures and temperatures which increase in each successive reactor, with vapor condensation between every oxidation zone. and recycling of the mother-liquors from one reactor to another.
  • a particular object of this invention is to provide a simpler, improved process for the oxidation of aromatic hydrocarbons with an oxidizing gas, and a more specific object of the invention isto provide a simpler, less expensive continuous process for the production of phthalic anhydride of great purity from ortho-xylene.
  • the new process of this invention uses relatively simple equipment, reactive conditions that are easier to control and provides a continuous process which produces very high yields of aromatic monoor polycarboxylic acids and/ or their corresponding anhydrides.
  • reaction mass In cases in which a hydrocarbon starting material is used which is able to form an anhydride or a mixture of anhydride and acid, the reaction mass should be hydrolyzed with water.
  • the reaction medium used in accordance with the invention essentially contains an oxidizing gas such as air, an aromatic hydrocarbon such as xylene, an inert solvent such as an aliphatic carboxylic acid like acetic acid, and a catalyst.
  • an oxidizing gas such as air
  • an aromatic hydrocarbon such as xylene
  • an inert solvent such as an aliphatic carboxylic acid like acetic acid
  • the disclosure specifically illustrates the use of ortho-, metaor para-xylene and mixtures of ortho-, metaand para-xylene starting materials; however, it should be understood that other alkylaromatic hydrocarbons could be oxidized in a similar manner.
  • alkylaromatic hydrocarbon (xylene) and acetic acid are preferably, but not necessarily, maintained between narrow limits, 5 to 30% by weight of hydrocarbon to 95 to 70% of acid being preferred without taking into account the amount of the catalytic system present in the reaction mixture.
  • the preferred catalysts used in this process are a mixture of hydrated heavy metal salts and/or halides, such as halides and/or other salts of cobalt and manganese.
  • the most preferred catalyst mixture is one containing equal or different molar proportions of cobalt acetate, manganese chloride and barium bromide, but other heavy metal salts could be used effectively.
  • the molar ratio of each of the three catalyst constituents is preferably between 1 and of moles per mole of ortho-xylene, which corresponds to 0.003 to 0.036 mole of catalyst per mole of hydrocarbon to be oxidized, but other ratios can be used.
  • the oxidation step of the process of this invention is carried out in a series of several reactors, for example, a series of three reactors may be used, the reaction liquid flowing from one reactor to another while the liquid is continually stirred with the help of recirculating pumps placed on the supply-circuits or with some other type of mechanical agitators.
  • Each of the reactors should be built or lined with a corrosion resisting material suitable for the operational conditions incurred in actual use.
  • the oxidation rates in every reactor should be maintained between optimum limits. Optimum oxidation rates will vary with the number and position in the series of the reactors employed. For example, when three reactors are used, it is best to maintain the oxidation 3 rate to less than 65% in the first reactor and less than in the third reactor.
  • the oxidation temperature may be between U0 and 230 C., and is preferably maintained between 140 and 200 C.
  • the pressure is maintained approximately constant in the oxidation system and the preferred pressures employed are between 3 and kg./cm. or more preferably between 4 and 10 kg./cm. in the temperature range indicated above.
  • the air required for oxidation is fed under suitable pressure through parallel conduits into the two last reactors so that the air or oxidizing gas runs countercurrently to the liquid aromatic hydrocarbon reaction mass.
  • This division of the oxidation air flow in the two last reactors creates a thermic balance favorable to maximum recuperation of heat produced in the reaction.
  • the excess hot gas which escapes from these last two reactors is sent as a whole to the first reactor through which it again passes countercurrently with respect to the liquid reaction mass. At the first reactor outlet, this hot gas is low in oxygen.
  • the gas passes from the first reactor through an azeotropic column in which it is dehydrated with the help of a hydrocarbon, such as benzene or similar dehydrating material, and the unreacted xylene and acetic acid vapors are removed.
  • a hydrocarbon such as benzene or similar dehydrating material
  • the xylene and acetic acid recovered at the foot of the distillation column are recycled to the first oxidation reactor while the benzene/ water mixture obtained at the top of the column is sent to a condenser where it is removed as an aqueous phase separation.
  • This process may be further modified by using a series of three reactors and distributing the total amount of air required for oxidation into each of the reactors; the hot gas coming out of the third reactor (in which the oxidation proportion is the lowest) is led into the first reactor (the one where the oxidation ratio is the highest) while the heat passing out of the second reactor is directly conducted into the azeotropic distillation column. The latter also received the hot gas from the first reactor.
  • Such distribution of air while producing a favorable thermic balance, offers the advantage of reducing notably the quantity of hot gas which gOes through the first reactor.
  • the reaction mass coming from the oxidation reactors contains essentially a mixture of ortho-phthalic acid and phthalic anhydride.
  • the reaction mass is hydrolyzed while still at boiling point temperature and atmospheric pressure using known processes.
  • the phthalic acid precipitate produced is removed by filtration, then, after a washing and centrifuging step, it is continuously dehydrated by heat at a temperature between 220 and 260 C. at atmospheric pressure.
  • the recovered crude phthalic anhydride is then rectified continuously at reduced pressure, without previous chemical and/ or thermal treatment.
  • reaction mas will contain isoand/or terephthalic acid, which is separated by filtration, then washed and centrifuged.
  • the mother liquors from the phthalic acid filtration and the precipitate washing liquors are preferably recycled continuously to the first oxidation reactor, after adjustments of the concentrations to desired levels of orthoxylene, acetic acid and catalyst.
  • This recycle procedure it is possible to send a portion of the mother- 4 liquors to the other reactors to vary'in each the effective residence time of the reactive medium.
  • FIGURE I shows a diagram of a preferred embodiment of the oxidation process of this invention.
  • the oxidation reaction takes place in each of the three reactors R R and R In the diagram shown in FIG- URE I, these reactors are at different levels with respect to one another, so that the reactive liquid may overflow from one reactor to another, the liquid passing through the overflow vessels 1 and 2 in the manner shown.
  • the ortho-xylene, aliphatic carboxylic acid and catalyst are fed into reactor R through conduits 3 and 4, and the liquid flows from reactor R to reactor R to reactor R after passing through overfiow vessels 1 and 2, and conduits 5 and 6.
  • the overflow tanks have branched connections with circulating pumps 7, 7 bis, and 8 which help regulate the flow in the manner illustrated.
  • the air necessary to complete the oxidation reaction is sent under pressure through pipe 9, through conduits 10 and 11, and the air enters the reactors R and R near the bottom. All of the excess air which escapes from the reactors R and R is sent to the bottom of reactor R through the conduit 12. Then the air passes through conduit 13 into distillation column D, into a condenser C, then into a decanter or settling tank C; from which it escapes through conduit 14.
  • Benzene is fed into the distillation column D through conduit 15 to wash and dehydrate the air that is now saturated with aliphatic acid, water and xylene vapors, which entered the column through conduit 13.
  • the acid and xylene recovered at the bottom of the distillation column are fed directly through conduit 1.6 to reactor R
  • the aqueous fraction removed in condenser C is drawn off through conduit 17 and the benzene fraction is recycled through conduit 18 into distillation column D.
  • reaction mass withdrawn from conduit 19, containing a mixture of ortho-phthalic acid and phthalic anhydride is subjected to successive operations of hydrolyzing, filtering of the acid phthalic precipitate, washing of this precipitate with acetic acid, centrifuging, dehydrating continuously, and rectifying the anhydride continuously under reduced pressure in known types of equipment not represented in the diagram.
  • the filtration mother-liquors and the acetic acid precipitate wash are mixed together, readjusted to the desired concentrations with added amounts of fresh reagent, then recycled through conduit 20' into the aromatic hydrocarbon feed conduit of primary reactor R
  • the mother-liquors can be recycled, entirely or partially, through conduit 21 into column D.
  • the catalyst contained a mixture of hydrated barium bromide, hydrated manganese chloride and hydrated cobalt acetate in a quantity of moles of each constituent per mole of xylene to be oxidized.
  • the average air flow varied between 1000 and 1500 l./hr. at the inlet of the reactors R and R and 950 to 1200 l./hr. at the outlet which is conduit 14 emerging from the condenser C.
  • the pressure was approximately uniform throughout the oxidation apparatus at approximately 6 kg./cm. absolute pressure, and the temperature in the reactors was between 157 to 162 C. in R 152 to 157 C. in R and 147 to 152 C. in R
  • the reaction mass drawn off through conduit 19 was continuously hydrolyzed by boiling for 1 hour at atmospheric pressure in the presence of water, filtered, washed with acetic acid, centrifuged to remove phthalic acid precipitate, and dehydrated by heating for 2 hours at 235 to 240 C. at atmospheric pressure.
  • the crude phthalic anhydride obtained was then rectified in 2 columns, continuously at sub-atmospheric pressure.
  • the chemical yield is defined by the ratio:
  • reaction mass drawn off through conduit 19 was continuously filtered; the isophthalic acid precipitate was washed with acetic acid and dried.
  • Example III The procedures of Example II were repeated, but paraxylene was substituted for meta-xylene. After 8 recyclings, terephthalic acid having a purity greater than 98% and an average chemical yield of 97% was obtained.
  • polyalkylphenyl hydrocarbon is selected from the group consisting of the dimethyl and trimethyl benzenes.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (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)
US504833A 1964-12-14 1965-10-24 Process of aromatic hydrocarbon oxidation Expired - Lifetime US3402184A (en)

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FR998922A FR1441453A (fr) 1964-12-14 1964-12-14 Procédé d'oxydation d'hydrocarbures aromatiques

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US (1) US3402184A (enrdf_load_stackoverflow)
AT (1) AT267504B (enrdf_load_stackoverflow)
BE (1) BE670307A (enrdf_load_stackoverflow)
CA (1) CA793870A (enrdf_load_stackoverflow)
DE (1) DE1267677B (enrdf_load_stackoverflow)
ES (1) ES320472A1 (enrdf_load_stackoverflow)
FR (1) FR1441453A (enrdf_load_stackoverflow)
GB (1) GB1065469A (enrdf_load_stackoverflow)
NL (1) NL6515180A (enrdf_load_stackoverflow)
SE (1) SE313047B (enrdf_load_stackoverflow)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4215053A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of ortho-phthalic acid and its conversion and recovery of phthalic anhydride
US4215056A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US4215054A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride
US4215052A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride
US4215055A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high _purity phthalic anhdyride
US4215051A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US4233227A (en) * 1979-10-05 1980-11-11 Standard Oil Company (Indiana) Phthalic anhydride formation and separation
US4234494A (en) * 1979-08-29 1980-11-18 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US5510521A (en) * 1995-03-27 1996-04-23 Eastman Chemical Company Process for the production of aromatic carboxylic acids
US6399790B1 (en) 1999-11-24 2002-06-04 General Electric Company Method for oxidation of xylene derivatives
US6465685B1 (en) 1999-11-24 2002-10-15 General Electric Company Method for oxidation of xylene derivatives
US6469205B1 (en) 1999-11-23 2002-10-22 General Electric Company Method for oxidation of xylene derivatives
US6649773B2 (en) 2002-03-22 2003-11-18 General Electric Company Method for the manufacture of halophthalic acids and anhydrides
US6657068B2 (en) 2002-03-22 2003-12-02 General Electric Company Liquid phase oxidation of halogenated ortho-xylenes
US6657067B2 (en) 2002-03-22 2003-12-02 General Electric Company Method for the manufacture of chlorophthalic anhydride
WO2004002933A1 (en) * 2002-06-27 2004-01-08 Eurotecnica Development & Licensing S.P.A. Process for the separation of the water produced in the catalytic oxidation of aromatic hydrocarbons to polycarboxylic aromatic acids
US7541489B2 (en) 2004-06-30 2009-06-02 Sabic Innovative Plastics Ip B.V. Method of making halophthalic acids and halophthalic anhydrides
CN102471210A (zh) * 2009-08-06 2012-05-23 鲁奇有限责任公司 制备邻苯二甲酸/邻苯二甲酸酐的工艺及设备
US20150226011A1 (en) * 2010-04-27 2015-08-13 Baker Hughes Incorporated Methods of forming polycrystalline compacts

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5328419B1 (enrdf_load_stackoverflow) * 1971-04-26 1978-08-15
JPS5328901B2 (enrdf_load_stackoverflow) * 1973-07-28 1978-08-17
JPS5614101B2 (enrdf_load_stackoverflow) * 1974-07-31 1981-04-02
JPS523030A (en) * 1975-06-25 1977-01-11 Mitsubishi Chem Ind Ltd Process for manufacturing high purity terephthalic acid
JPS5291835A (en) * 1976-01-29 1977-08-02 Mitsubishi Chem Ind Ltd Prepation of terephtalic acid for direct polymerization
JPS52106833A (en) * 1976-02-24 1977-09-07 Matsuyama Sekyu Kagaku Kk Production of telephthalic acid for direct polymerization
NL188282C (nl) * 1977-04-04 1992-05-18 Montedison Spa Werkwijze voor de synthese van tereftaalzuur door oxyderen van p-xyleen in azijnzuuroplossing.

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3092658A (en) * 1957-08-12 1963-06-04 Standard Oil Co Continuous system for oxidizing substituted aromatic hydrocarbons and producing carboxylic acids
US3155718A (en) * 1956-11-21 1964-11-03 Ici Ltd Process for the oxidation of organic compounds

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155718A (en) * 1956-11-21 1964-11-03 Ici Ltd Process for the oxidation of organic compounds
US3092658A (en) * 1957-08-12 1963-06-04 Standard Oil Co Continuous system for oxidizing substituted aromatic hydrocarbons and producing carboxylic acids

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4215053A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of ortho-phthalic acid and its conversion and recovery of phthalic anhydride
US4215056A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US4215054A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride
US4215052A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride
US4215055A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Production of liquid ortho-phthalic acid and its conversion to high _purity phthalic anhdyride
US4215051A (en) * 1979-08-29 1980-07-29 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US4234494A (en) * 1979-08-29 1980-11-18 Standard Oil Company (Indiana) Formation, purification and recovery of phthalic anhydride
US4233227A (en) * 1979-10-05 1980-11-11 Standard Oil Company (Indiana) Phthalic anhydride formation and separation
US5510521A (en) * 1995-03-27 1996-04-23 Eastman Chemical Company Process for the production of aromatic carboxylic acids
US6469205B1 (en) 1999-11-23 2002-10-22 General Electric Company Method for oxidation of xylene derivatives
US6465685B1 (en) 1999-11-24 2002-10-15 General Electric Company Method for oxidation of xylene derivatives
US6399790B1 (en) 1999-11-24 2002-06-04 General Electric Company Method for oxidation of xylene derivatives
US6649773B2 (en) 2002-03-22 2003-11-18 General Electric Company Method for the manufacture of halophthalic acids and anhydrides
US6657068B2 (en) 2002-03-22 2003-12-02 General Electric Company Liquid phase oxidation of halogenated ortho-xylenes
US6657067B2 (en) 2002-03-22 2003-12-02 General Electric Company Method for the manufacture of chlorophthalic anhydride
WO2004002933A1 (en) * 2002-06-27 2004-01-08 Eurotecnica Development & Licensing S.P.A. Process for the separation of the water produced in the catalytic oxidation of aromatic hydrocarbons to polycarboxylic aromatic acids
US20050272951A1 (en) * 2002-06-27 2005-12-08 Noe Sergio Process for the separation of the water produced in the catalytic oxidation of aromatic hydrocarbons to polycarboxylic aromatic acids
US7541489B2 (en) 2004-06-30 2009-06-02 Sabic Innovative Plastics Ip B.V. Method of making halophthalic acids and halophthalic anhydrides
US7732559B2 (en) 2004-06-30 2010-06-08 Sabic Innovative Plastics Ip B.V. Method of making halophthalic acids and halophthalic anhydrides
CN102471210A (zh) * 2009-08-06 2012-05-23 鲁奇有限责任公司 制备邻苯二甲酸/邻苯二甲酸酐的工艺及设备
US20150226011A1 (en) * 2010-04-27 2015-08-13 Baker Hughes Incorporated Methods of forming polycrystalline compacts
US9500039B2 (en) * 2010-04-27 2016-11-22 Baker Hughes Incorporated Methods of forming polycrystalline compacts

Also Published As

Publication number Publication date
DE1267677B (de) 1968-05-09
NL6515180A (enrdf_load_stackoverflow) 1966-06-15
CA793870A (en) 1968-09-03
FR1441453A (fr) 1966-06-10
SE313047B (enrdf_load_stackoverflow) 1969-08-04
BE670307A (enrdf_load_stackoverflow) 1900-01-01
GB1065469A (en) 1967-04-12
AT267504B (de) 1969-01-10
ES320472A1 (es) 1966-11-16

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