• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    In a process for the preparation of fiber-grade terephthalic acid from intermediate stage crude dimethyl terephthalate, the crude dimethyl terephthalate, which has a limited content of intermediate oxidation products including a content of terephthalaldehydic acid methyl ester of up to 0.1% by weight based on the weight of the crude dimethyl terephthalate, is hydrolyzed with water at a weight ratio of the crude dimethyl terephthalate to water of between 3:1 and 0.1:1 and at a temperature between 140 DEG C. and 350 DEG C. and under a pressure required to maintain a liquid phase (e.g., from 6 to 200 bars) to produce a reaction mixture containing crystalline fiber-grade terephtalic acid and thereafter the terephthalic acid is recovered from the reaction mixture. The initial crude dimethyl terephthalate used as a starting material is obtained from a crude ester mixture produced by the oxidation of p-xylene and/or methyl p-toluate with oxygen-containing gases in the presence of heavy metal-containing oxidation catalyst at an elevated temperature and under an elevated pressure and by esterification of the oxidation mixture with methanol at an elevated temperature and elevated pressure followed by separating the resulting crude ester mixture by distillation into a methyl p-toluate enriched fraction, a residual high-boiling fraction and the crude dimethyl terephthalate having the limited content of intermediate oxidation products.
    公开号:SU1041029A3
    申请号:SU802910350
    申请日:1980-04-18
    公开日:1983-09-07
    发明作者:Шенген Антон；Шрайбер Георг；Шредер Гейнц
    申请人:Динамит Нобель Аг (Фирма)；
    IPC主号:
    专利说明:

    This invention relates to organic chemistry, specifically to a method for producing terephthalic acid, which is used in the manufacture of synthetic fibers. A known method for producing terephthalic acid by oxidation of p-xyl la 1. The closest to the present invention is a method for producing terephthalic acid — by oxidizing p-xolol and / or p-toluic acid — methyl ester with an acid-like gas in the presence of a heavy metal β catalyst with elevated temperature and pressure, etherifying the oxidation mixture with methanol at elevated temperatures and further distillation, distillation of dimethyl terephthalate, which is then subjected to hydrolysis with water at 10-350 ° C under pressure, and the subsequent isolation of the target product by crystallization 2. However, when using lime. The purity of the target product (99,) is insufficient due to the content of terephthalaldehyde acid methyl ester in dimethyl terephthalate, distilled from the esterification product. The purpose of the invention is to increase the purity of the target product. The goal is achieved by the fact that terephthalic acid is obtained by oxidation of p-xyl.ol and / or p-toluic acid methyl ester with oxygen-containing gas in the presence of a catalyst based on a heavy metal at elevated temperature and pressure, the esterification of the oxidation mixture with methanol at elevated temperature and pressure, distillation of dimethyl terephthalate, distillation of the obtained product at a temperature of 130-190 ° C, pressure of 15-100 mbar and a reflux number 0, then hydrolysis with water at 1t-350 ° C under pressure, separation of the product g droliza thickened suspension on the solid terephthalic acid product and a mother liquor which is fed in countercurrent processing desalted .vodoy at 150-300 s, and a liquid phase containing the remainder of the mother liquor podavaemyJO. for processing, crystallization, followed by the isolation of the target product by common methods. Distinctive features of the process are distillation of dimethyl terephthalate after distillation at a temperature of 130-190 ° C, a pressure of 15-100 mbar and a reflux ratio of 0.3: 1-10: 1, and before crystallization the hydrolysis product is subjected to countercurrent treatment with desalted water at 150-300 ° C with the subsequent separation of water from the target product. hydrolysis is divided into a thickened suspension of solid terephthalic acid and mother liquor, which is fed to countercurrent treatment with water, and the liquid phase containing the remaining amount of mother liquor, which is fed to the processing. . On. The drawing shows the technological scheme of the proposed method. According to the technological scheme, to the stage G of oxidation, g-Xylene is fed through pipeline 1, p-toluic acid methyl ester through pipeline 2, air through pipeline 3 and cobalt-manganese catalyst through pipeline k. From stage 1 of oxidation, exhaust gas is discharged through pipeline 5, the waste water through the pipeline 6 and the oxidation product through the pipeline 7. The oxidation product is fed to the esterification stage G1 with fresh methanol fed through the pipeline 8 and the recovered methanol supplied through the pipeline 9 from stage 1P The fraction of the fraction withdrawn from esterification stage II via the pipeline 10. This fraction is separated into wastewater discharged through line 11, lightly boiled components withdrawn through line 12, benzoic acid methyl ester withdrawn through line 13 and containing complex methyl ether and -toluic acid fraction supplied through pipeline 1Л to collector 15. The esterification product through pipeline 16 is fed to d, two-stage vacuum distillation P /, and the head product of the first stage, which is a fraction of complex m p-toluic acid ethyl ester, is fed to collection 15 via pipeline 17, and the second product, represented by a fraction of dimethyl terephate, is fed to distillation V, carried out at temperature 130-190 ° C, pressure 15-100 mbar and a reflux ratio of 0.3: 1-10: 1 The bottom product of the second distillation stage /, which is a high-boiling residue, is withdrawn through line 18. At distillation V, a terephthalaldehyde acid methyl ester fraction is obtained as the main product withdrawn through the pipeline 19. and dimethylter fraction ephthalate as a bottom product supplied via line 20 to the VJ hydrolysis with water supplied via line 21. The hydrolysis is carried out at YO-350 ° C under pressure. The hydrolysis product is fed through line 22 to crystallization VII, after which it is divided into a thickened suspension of solid terephthalic acid and a liquid phase containing the remaining amount of the mother liquor. Condensed suspension is fed through conduit 23 to countercurrent treatment of VIII with desalted water, carried out at 150-300 C. On the countercurrent treatment with desalted water, a filtrate is obtained, which, together with the liquid phase obtained by separating the crystallized hydrolysis product, is fed via conduit 2 to crystallization 10 by cooling and at atmospheric pressure. Wherein; a water-methanol phase is obtained, which is fed through conduit 25 to methanol distillation stage X, and the mother liquor containing crystals is subjected to separation by centrifugation. This gives a fraction of solids fed through conduit 26 to the stage where the aqueous phase from the stage 27 also passes from X, as well as the filtrate fed through line 28 to stage X. At stage R, methanol with a low water content is distilled off, which is fed through line 29 to the TTT stage. Before serving on stage XJ from the aqueous phase obtained in stage .E. the byproducts are separated, which are withdrawn through pipeline 30. The suspension obtained in stage VI of the countercurrent treatment is fed through a hydrocyclone and pipeline 31 to crystallize XTT terephthalic acid via cooling at atmospheric pressure. Then, the suspension is separated by centrifuging at stage X111. where pipeline 32 serves desalinated water. The terephthalic acid obtained at the centrifugation stage through conduit 33 is fed to the drying XIV, and then withdrawn through the conduit Zn. The water obtained at stages XIII and XIV through pipelines 35 and 36 is fed to collector 37, from which part of the water through the heat exchanger and pipe 38 is recycled to stage VII1, and the rest of the water through pipe 39 serves to stage) II. The result is terephthalic. acid with a color index of k-7 APHA versus 70 APHA according to method 2 Zi purity up to .. The terephthalic acid obtained by the proposed method is necessary to obtain linear polyesters used to make light-resistant white textile materials. It is also used as a catalyst in the production of L-chloro-5-amino-2-phenyl-3 (2H) -pyridazinone, which is a raw material for the preparation of dyes and plant protection products. The following examples use the following conditional abbreviations:. DMT - dimethyl terephthalate, MMT - monogram methyl terephthalate, MEPTK - methyl ester of h-toluic acid, PTK - p-toluic acid, METAK methyl ester of terephthalaldehyde acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DME - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate, DMO - dimethylmetrotehl acid, DNI - dimethyl isophthalate; high-boiling components, TPA - terephthalic acid, IFC - isophthalic acid, OFA - orthophthalic acid, IMI - monomethylisophthalate. MMO is mono-methyl ortho phthalate; SO is the teo-phthalaldehyde acid. Example. A mixture of 13,808 kg / cp-xylene and 31,691 kg / h of ri-toluic acid monomethyl ester is subjected to oxidation of 75,318 kg / h of air in the presence of kg / h of a catalyst based on cobalt and manganese (10: 1) in the form of acetate, dissolved in water. The oxidation is carried out in a cascade of three reactors with increasing from 140 to temperature and increasing from L to 8 bar pressure. 51 8b5 kg / h of oxidation product are obtained, which is subjected to esterification with 26 13 kg / h of methanol at a temperature and pressure of 20 bar. This gives A2 658 kg / h of the mixture, which is subjected to two-stage vacuum distillation, the first stage of which is carried out at a temperature, a pressure of 100 mbar and a reflux ratio of 2: 1, and the second stage - at a temperature of 180 ° С, i pressure of 50 mbar and reflux ratio 0.3: 1. In the second stage, 23,582 kg / h of the head product, consisting of 96.13 DMT, 1.2% MMT, 0.1% M9PTA, 0.7% PTC, 0.7% METAC, 0.36%, are obtained. DMO, OH, DAYS and 0.35% 8K. This mixture is subjected to distillation at a temperature and pressure of 20 bar. This gives 2,658 kg / h of a mixture, which is subjected to two-stage vacuum distillation, the first stage of which is carried out at a pressure of 100 mbar and a reflux ratio of 2: 1, and the second stage at a temperature of 180s, a pressure of 50 mbar and a reflux ratio of 0, 3: 1. In the second stage, 23,582 kg / h of the head product are obtained, consisting of 96.13% DMH, 1.2% MMT, 0.1% MPTA, 0.7% PTC, 0.7% METAC, 0.36% DME, 0.6% DMI and 0.35% VK. This mixture is subjected to distillation at a temperature of 180 ° C, a pressure of 55 mb and a light weight of 8: 1. In this case, 1,179 kg / h of the head product and 22,403 kg / h of the bottom product are obtained. The head product consists of 68.2% DMT, 13.1% METAC and IV, other identifiable by-products. The bottom product consisting of 97.6% DMT, 0.05% MEPTA, 0,% PTC, 0.05% METAC, 0.2% DMO, 0.1% DMI, 1.0% MMT and 0.3 % BK, and IT 278 kg / h of the aqueous phase consisting of 89.67% water, 0.05% methanol, 2.35% TFA, 0.15% IFC, 0.07% OFA, 0.92% DMT , 0.01% DMI, 0.01% DMO, 6, MMT, 0.05% MMI, 0.03% MMO 0.23% PTC, 0.06% SO and 0.18% VK, are fed for hydrolysis at temperature of 250 ° C and a pressure of 50 bar for 0 min. In this case, 136 .681 kg / product is obtained, consisting of 71.98% water, 5.35% methanol, 11.45% TFA in dissolved form, 25% TFA in solid form, 0.17% IFA, 0 , 08% OFA, 0.82 DMT, 0.01% DMI, 0.01% DMO, M | 1T, 0.06% MMI, 0, OZMMO, 0.26% PTC, 0.07% SO and 0, 20% VK. The hydrolysis product is subjected to crystallization by cooling to 200 ° C and depressurization to 20 bar, after which it has the composition: 71.98% water, 5.35% methanol, 1.93% TFA in dissolved form, 13.76 TFA in solid form , 0.17% IFC, 0.08% OFA, 0.82% DMT, 0.01% DMI, 0.01% DMO, 5.29% MMT, 0.06% MMI, 0.03% MMO 0, 26% PTC, 0.07% TAK and 9.02 VK. The product of hydrolysis in a hydrocyclone is divided into a thickened suspension of solid terephthalic acid and mother liquor and on. the liquid phase containing the remaining amount of the mother liquor. The resulting condensed suspension is fed to countercurrent treatment with desalted water at a temperature of 200 ° C and a pressure of 20 bar, which is removed from the washing and drying stage of the target product and supplied in the amount of 30,011 kg / h. At this stage, a liquid phase is obtained, which is combined with the liquid phase obtained in the hydrolysis product separation stage. This gives 119 80 kg / h of the composition phase: 83.69% water, 6.10% methanol, 2.25 % TFA, 0.19% .IFA, 0.09% OFA, 0.9 +% DMT, 0., 1% DMI, 0.055 DMO, 6, MMT, 0.05% MMI, 0.03% mmb; 0.30% PTC, 0.07% TAC and 0.2.2% VK, which is fed for processing, aimed at the release of methanol and suitable products, like MMT. In addition, at the stage of countercurrent treatment with desalted water, b 888 kg / h are obtained, suspensions of the composition: 59.98% water, 1.08% TFA in dissolved form and 38, TFA, THAT through a hydrocyclone (the main fraction of which is recycled to countercurrent treatment fed to crystallization by cooling to C LLP and depressurizing to atmospheric, followed by centrifuging while rinsing 29,384 kg / h of desalinated water and drying. 18 750 kg / h of TFA with 5 APHA color (5% solution of TFA in dimethylformamide) are obtained that corresponds to the purity of 99.999%. 119 804 kg / h of this liquid phase are carried out as follows: First, the phase is cooled to a simultaneous release of pressure to atmospheric. At the same time, TPA and MMT crystallize and the resulting secondary steam (23 050 kg / h) composition: 85.7% water and 14.3% of methanol are fed to the distillation. The TFA and MMT mother liquor obtained at the crystallization stage is centrifuged to yield 11 451 kg / h of solid phase composition: 9.31% water, 0.47% methanol, 22.94% TPA, 0.03% IFC, 0.01% OFA, 7.27% DMT, 0.01% DMI, 0.0.1% DMO, 56.86% MMT, 0.01% MMM, 0.01% MMO, 0.04% PTC, 0.01% SO and 0.03% VC, which together 49,574 kg / h of a bottom product aqueous methanol and distilling off the
    27 511 kg / h of desalinated water from the stage of washing and drying are fed to the hydrolysis of dimethyl terephthalate.
    The aqueous phase obtained at the centrifugation stage is 85,303 kg / h of a 5-volt state: 93, 13% water, 4.65% methanol., FC, 0.26% IFA, 0.13% OFA, 0.3 GDMT, 0, OP DMI, 0, OU DMO, O.ii MMT, 0.09% PIM, 0.04% MMO, .0, PTK,. 0.1% JAK and 0.31% BK are also fed to the methanol distillation. In this case, as a quality. At a temperature of 65 ° C and a pressure of 1 bar, 7,295 kg / h of the mixture consisting of 99.5% methanol and 0.5% water of the mixture are recirculated for esterification, and as a bottom product at temperature and pressure. 1 bar is obtained of 75,316 kg / h consisting of 9.8.12% water, 0.06% TFA, 0.21% IFA, O, -t OPC, .20 0.29% DFT, 0.01% DMY, 0.01% DMO, MMT, 0.07% MMM, 0, OJ MMO, 0.35% PTC, 0.09% TAK, and 0.26% BK mixture, from which 25 kg / h are separated before recycling that feed for the isolation of by-products.
     Example 2 is repeated. Example 1 is repeated, with the difference that the head product of the second stage of the distillation of the esterification product is subjected to distillation at 30 ° C at 190 ° C, pressure of 100 mbar, and reflux ratio 10: 1, 18 750 kg / h of terephthalic are obtained. acid with color 4 ARNA.
    Example 3. Example 1 is repeated with the difference that the esterification is carried out at a temperature and pressure of 25 bar, and the head product of the second stage of the distillation of the esterification product is subjected to distillation at a temperature of 130 ° C, a pressure of 15 mbar and a reflux number 0. 18 750 kg / h of terephthalic acid are obtained with a color of 7 ARCA.
    Example 4. Example 1 is repeated, with the difference that G1 countercurrent treatment with desalted water is carried out at a temperature of 300 ° C. 18 750 kg / h of terephthalic acid with color are obtained, 5 APHA.
    At measure 5. Repeat example 1 with that. the difference is that countercurrent treatment with desalted water is carried out at 150 ° C. Thus receive 18750 kg / terephthalic acid with a color of 6.5 APHA.
    PRI me R 6 {comparative, according to the prototype). Example 1 is repeated, with the difference that the head product of the second stage of the distillation of the esterification product is not subjected to countercurrent treatment with desalted water. In this case, 18,690 kg / y of terephthalic acid are obtained with a color of 70 APHA, which corresponds to the purity
    99.2%; .
    r
    //
    29
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    thirty

    Z8
    权利要求:
    Claims (1)
    [2]
    2. The patent of Germany Ν ’1618503, cl. 120, published. 1971. 1 METHOD FOR PRODUCING TERPHTHALIC ACID, by oxidation of p-xylene and / or methyl ester of η-toluic acid with an oxygen-containing gas in the presence of a heavy metal catalyst at elevated temperature and pressure, esterification of methane oxidation mixture ... · scrap at elevated temperatures and dav. liquefaction, distillation of dimethyl terephthalate.a "which is subjected to hydrolysis with water at a temperature of 140-350 ° C under pressure, and the subsequent isolation of the target product by crystallization, with the exception of the fact that> in order to increase the purity of the target product, after distillation, the dimethyl terephthalate is subjected to distillation at a temperature of 130-190 ° C, a pressure of 15 “10 mbar and a reflux ratio of 0.3: 1 - 10: 1, and before crystallization, the hydrolysis product is separated into a condensed suspension of solid terephthalic acid and the mother liquor, which is fed to a countercurrent processing · Deer of water at a temperature of 15O-ZOO ° C, followed by crystallization of the desired product, and a liquid phase containing the remainder of the mother rast-. thief served for recycling.
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    同族专利:
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    NL7905318A|1980-10-23|
    DD146822A5|1981-03-04|
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    PH22194A|1988-06-28|
    BG60054A3|1993-08-16|
    GB2047704A|1980-12-03|
    DE2916197C2|1982-01-28|
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    YU159679A|1982-08-31|
    ES482621A1|1980-04-01|
    EG14817A|1985-06-30|
    DE2916197A1|1980-10-23|
    UA7015A1|1995-03-31|
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    PL123543B1|1982-10-30|
    BR7904770A|1980-12-02|
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    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    DE1112973B|1954-09-08|1961-08-24|Ici Ltd|Device for purifying terephthalic acid|
    US2794832A|1955-06-20|1957-06-04|Shell Dev|Crystallization and separation of crystals|
    US2992168A|1959-07-09|1961-07-11|Eastman Kodak Co|Process of purifying dimethyl terephthalate and other compounds which sublime|
    US3108132A|1962-01-16|1963-10-22|Standard Oil Co|Purification of dmt by filtration|
    US3396087A|1966-01-10|1968-08-06|Exxon Research Engineering Co|Dimethylterephthalate recovery from paraxylene feed|
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    DE1299627B|1966-08-31|1969-07-24|Dynamit Nobel Ag|Process for the production of the purest terephthalic acid|
    US4118313A|1973-11-03|1978-10-03|Dynamit Nobel Aktiengesellschaft|Process and apparatus for mass transfer between heterogeneous systems|DE3011858C2|1979-04-21|1982-11-25|Dynamit Nobel Ag, 5210 Troisdorf|Process for the production of terephthalic acid from crude dimethyl terephthalate by continuous hydrolysis with water|
    DE3041293C2|1979-04-21|1988-07-21|Huels Troisdorf Ag, 5210 Troisdorf, De|
    DE2938163C2|1979-09-21|1988-08-11|Huels Troisdorf Ag, 5210 Troisdorf, De|
    DE3044617C2|1980-11-27|1985-09-26|Dynamit Nobel Ag, 5210 Troisdorf|Process for the production of terephthalic acid from dimethyl terephthalate as an intermediate|
    JPS6312992Y2|1982-04-30|1988-04-13|
    JPH0252372B2|1982-11-05|1990-11-13|Mitsubishi Electric Corp|
    DE3407912C1|1984-03-03|1985-05-09|Dynamit Nobel Ag, 5210 Troisdorf|Process for the preparation of terephthalic acid via dimethyl terephthalate from p-xylene and methanol|
    JPH0420600Y2|1987-05-14|1992-05-12|
    DE3904586A1|1989-02-16|1990-08-23|Huels Chemische Werke Ag|METHOD FOR THE PRODUCTION OF DMT INTERMEDIATE PRODUCT OF CERTAIN PURITY, AND ITS PROCESSING TO PURE DMT AND / OR MEDIUM OR HIGH PURITY TEREPHTHALIC ACID|
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    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    DE2916197A|DE2916197C2|1979-04-21|1979-04-21|Process for the production of terephthalic acid from dimethyl terephthalate as an intermediate|
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