CN101402564A - Dissolution processing method for CTA draff in PTA production - Google Patents
Dissolution processing method for CTA draff in PTA production Download PDFInfo
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- CN101402564A CN101402564A CNA2008100710768A CN200810071076A CN101402564A CN 101402564 A CN101402564 A CN 101402564A CN A2008100710768 A CNA2008100710768 A CN A2008100710768A CN 200810071076 A CN200810071076 A CN 200810071076A CN 101402564 A CN101402564 A CN 101402564A
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Abstract
The invention relates to a solvent processing method for CTA residue during the PTA production. The method comprises the following steps: mixing the CTA residue and water into slurry which is dissolved and filtrated to obtain mixed acid filter cake and hot crude benzoic acid filtrate; injecting the obtained hot crude benzoic acid filtrate into a cooling pond for natural cooling and crystallization, and obtaining crude benzoic acid filter residue and aqueous solution after filtration; injecting the obtained crude benzoic acid filter residue into a sintering kettle for heating and melting, and obtaining a big block of crude benzoic acid after cooling and recrystallization in a reception tray; and adding the obtained big block of the crude benzoic acid into a distillation tower for benzoic acid distillation, and obtaining the industrial-grade benzoic acid from the top of the tower through the heat exchange and separation of filler gas liquid in the distillation tower. The method which carries out the synthesized processing of the CTA residue in the PTA production through the solvent processing method can sufficiently extract various valuable constituents in the CTA residue, thereby not only solving the problem of processing the CTA residue during the PTA production, but also creating great economic benefits. Therefore, the method has high promotion and application values.
Description
Technical field
The present invention relates to the recoverying and utilizing method of residue in the petrochemical complex production, be meant the dissolution processing method of CTA residue in the PTA production especially.
Background technology
In PTA (pure terephthalic acid) factory, when generating CTA (crude terephthalic acid) by PX (p-Xylol) oxidation, have a large amount of side reactions to take place, the by product of generation and unreacted raw material enter in the mother liquor, and mother liquor reclaims the solid impurity that produces behind the acetic acid through pervaporation and is called the CTA residue.
The component complexity of CTA residue, often form and change, mainly contain following composition: phenylformic acid, terephthalic acid, m-phthalic acid, phthalic acid, other organic substances and Co, Mn organic salt catalyzer etc., because the component of CTA residue is complicated and form unfixing, its recycling cost is higher, old friends adopt following method to handle usually: the one, directly the CTA residue is buried, though simple, environment is caused immeasurable risk; The 2nd, burn, can produce great amount of carbon dioxide, will aggravate Greenhouse effect; The 3rd, add alkali and carry out biochemical treatment, generate a large amount of biochemical sludges, also be to adopt to bury processing, can cause immeasurable risk to environment equally.And in fact, the phenylformic acid in the CTA residue, terephthalic acid, m-phthalic acid, phthalic acid, other organic substances and Co, Mn organic salt catalyzer etc. all is valuable constituents, can recycle fully.
At present, to the recycling of CTA residue mainly based on following two kinds of thinkings: the one, only extract wherein a kind of composition, " from the terephthalic acid oxidation residua, reclaim benzoic method " as Chinese patent application 01127075.6, adopt dissolving and crystalline method earlier with terephthalic acid oxidation residua and water dissolution, carry out vacuum filtration then, filtrate is carried out crystallisation by cooling, again the material behind the crystallisation by cooling is carried out centrifugation, filter cake is the phenylformic acid crude product after drying, is the pure product of phenylformic acid after making with extra care; U.S. Patent number 7285677 for another example, for reclaim the method for catalyzer from the CTA residue.
Second kind of thinking is to carry out esterification treatment with adding alcohol, as Chinese patent application 200310103435.0 " a kind of terephthalic acid oxidation residua recycle method ", adopt that twice esterification reaction of organic acid, rectification method separate, processes such as recrystallization method is refining, transesterification reaction recycle petrochemical compleies and produce terephthalic acid, m-phthalic acid and phenylformic acid in the residues; " recycle the method for terephthalic acid raw product residue " as Chinese patent application 03115282.1, the method that relates to a kind of recycling terephthalic acid raw product residue (being the CTA residue), it is included in the catalyzer that adds lipid acid, dibasic alcohol and catalytic amount in the described residue, generate mixing thick ester, wherein residue through catalytic esterification: lipid acid: the mol ratio of dibasic alcohol is 1.0: (0.2-9.0): (0.8-5.0); Chinese patent application 02137441.4 " a kind of commercial run that utilizes terephthalic acid raw product residue to produce benzene carboxylic acid ester class " for another example, relate to a kind of commercial run that utilizes terephthalic acid raw product residue to produce benzene carboxylic acid ester class, it is characterized by: with 1～8: 1 agent dregs ratio, about positive and negative 40 degree of selected solvent boiling point, under normal pressure or the pressurized conditions, stop dissolving in 0.1～5 hour, telling the dissolved liquid phase does not dissolve mutually with the band solid, in two-phase, add di-alcohols and unit alcohols material and catalyzer respectively and carry out esterification, reclaim solvent in the time of esterification, obtain two kinds of benzene carboxylic acid esters products after esterifying liquid is refining.
Above-mentioned first kind of recoverying and utilizing method to the CTA residue only is that a kind of composition in the residue is reclaimed, and other compositions are discarded once more as residue, and its processing also is very big environmental problem; Second kind of recoverying and utilizing method to the CTA residue adopts esterification treatment can consume a large amount of raw materials such as alcohols, and not only cost recovery is higher, and technology is comparatively complicated, is difficult to promote the use of.
Summary of the invention
Main purpose of the present invention is to overcome the shortcoming of prior art, and the dissolution processing method of CTA residue in a kind of PTA production is provided, but the various valuable constituents in the comprehensive utilization of C TA residue.
The present invention adopts following technical scheme: the CTA residue is that PX produces isolated a part of impurity in the CTA process through catalyzed oxidation in the PTA production process, its main component be phenylformic acid, pure mixed phthalic acid (to,, phthalic acid) and other organic substances and Co, Mn catalyzer etc., the present invention is according to the difference of each moiety solubleness in water and other characteristics separately, comprehensive treating process, each valuable constituent in the CTA residue is fully extracted, and concrete steps are as follows:
1) CTA residue and water are made into slurry, are invested in and are heated to 95～100 ℃ in the dissolution kettle, constant temperature 15～20 minutes, filtered while hot obtains nitration mixture filter cake and crude benzol formic acid hot filtrate.Step 1) mainly is to utilize the marked difference of acid not of the same race solubleness in water in the CTA residue, and the rough segmentation of CTA residue is become nitration mixture filter cake and crude benzol formic acid hot filtrate two portions.Such as, in the time of 95 ℃, the solubleness of phenylformic acid in water is 6.8g/100g, the solubleness of phthalic acid in water is 19.0g/100g, the solubleness of p-methylbenzoic acid in water is 8g/100g, and the solubleness of terephthalic acid in water is less than 0.04g/100g, the solubleness of m-phthalic acid in water is 0.24g/100g, the solubleness of inclined to one side three benzene tricarboxylic acids in water is also lower, so the main component of nitration mixture filter cake is terephthalic acid, m-phthalic acid and inclined to one side three benzene tricarboxylic acids, can be directly as the raw material of producing unsaturated polyester, softening agent; Crude benzol formic acid hot filtrate then comprises more phthalic acid impurity.
2) the crude benzol formic acid hot filtrate that obtains is injected cooling pool and naturally cool to 30～40 ℃ of crystallizations 24 hours, obtain the crude benzol formic acid filter residue and the aqueous solution after the filtration.Owing to have the part solid residue to enter filtrate during filtered while hot in the step 1), and the solubleness maximum of phthalic acid, almost completely be dissolved in the filtrate, so benzoic impurity is more, again since hot filtrate in the phenylformic acid saturation solubility also have only about 6g/100g, so step 2) in the crystallisation by cooling particle less, so behind the crystallisation by cooling dehydration the difficulty, it is moisture up to 60～70% to obtain filter residue, must slough most water through recrystallization.
3) the crude benzol formic acid filter residue injection sintering still that obtains being heated to 95～100 ℃ dissolves fully, put into a receiving plate cooling recrystallize and obtain bulk crude benzol formic acid, otherwise when entering rectifying owing to the bigger crude benzol formic acid of water content, because 100 ℃ of phenylformic acid distil rapidly, and can volatilize simultaneously with water vapour and make the rectifying yield reduce greatly or can not get phenylformic acid.
4) the bulk crude benzol formic acid that obtains is joined in the rectifying tower heat, under normal pressure water vapor is steamed earlier, the water vapor water of generation absorbs; Treat water vapor after rolling, change phenylformic acid rectifying state over to, the caloic exchange separation of process rectifying tower filler gas-liquid obtains content from cat head and is not less than 99% technical grade phenylformic acid.Contain impurity such as phthalic acid, terephthalic acid and p-methylbenzoic acid in the crude benzol formic acid, the vapour pressure of these impurity all is lower than phenylformic acid, thereby stays and form rectification residue in the rectifying tower.
5) with step 2) in the aqueous solution that obtains adopt storng-acid cation exchange resin to carry out ion exchange treatment to extract Co, Mn catalyzer.
Wherein, before carrying out step 1), at first to gather CTA residue sample and measure benzoic acid content, determine the concentration proportioning of CTA residue and water according to benzoic acid content in the CTA residue that records.
Wherein, water remaining behind the extraction with aqueous solution Co in the step 5), the Mn catalyzer is reclaimed recycling.
By the above-mentioned description of this invention as can be known, compare with prior art, the present invention adopts the method for dissolution process that CTA residue in the PTA production is carried out comprehensive treating process, various valuable constituents in the CTA residue fully can be extracted, not only solved the processing difficult problem of CTA residue during PTA produces, simultaneously also can create very big economic benefit, have very high popularizing value.
Embodiment
The following is three embodiment of the dissolution processing method of CTA residue in the PTA production of the present invention:
Embodiment one
At first from the CTA residue of 6000KG, get three parts of samples, the benzoic acid content that records in the CTA residue is about 25%, according to the benzoic acid content that measures CTA residue and water were made into slurry by weight 1: 4, be invested in and be heated to 95 ℃ in the dissolution kettle, behind the constant temperature 18 minutes, filtered while hot obtains nitration mixture filter cake and crude benzol formic acid hot filtrate.The nitration mixture filter cake that obtains is collected pack, and the main component of nitration mixture filter cake is terephthalic acid, m-phthalic acid and inclined to one side three benzene tricarboxylic acids, can be directly as the raw material of producing unsaturated polyester, softening agent.
The crude benzol formic acid hot filtrate that then previous step is obtained injects cooling pool and naturally cools to 35 ℃ of crystallizations 24 hours, obtains the crude benzol formic acid filter residue and the aqueous solution after the filtration.Adopt storng-acid cation exchange resin to carry out ion exchange treatment the aqueous solution and extract Co, Mn catalyzer.Remaining water reclaims recycling after extracting Co, Mn catalyzer
The crude benzol formic acid filter residue that then previous step is obtained injects the sintering still and is heated to 95 ℃, and constant temperature 30 minutes after confirming to dissolve fully, is put into a receiving plate cooling recrystallize while hot, removes the upper strata stillness of night, obtains bulk crude benzol formic acid.
The bulk crude benzol formic acid that at last previous step is obtained joins in the rectifying tower and heats, and under normal pressure water vapor is steamed earlier, and the water vapor water of generation absorbs; Treat water vapor after rolling, change phenylformic acid rectifying state over to, obtain the technical grade phenylformic acid 1025KG of content 99.10% through the caloic exchange separation of rectifying tower filler gas-liquid from cat head.
Embodiment two
At first from the CTA residue of 10000KG, get three parts of samples, the benzoic acid content that records in the CTA residue is about 20%, according to the benzoic acid content that measures CTA residue and water were made into slurry by weight 1: 3.8, be invested in and be heated to 100 ℃ in the dissolution kettle, behind the constant temperature 20 minutes, filtered while hot obtains nitration mixture filter cake and crude benzol formic acid hot filtrate.The nitration mixture filter cake that obtains is collected pack, and the main component of nitration mixture filter cake is terephthalic acid, m-phthalic acid and inclined to one side three benzene tricarboxylic acids, can be directly as the raw material of producing unsaturated polyester, softening agent.
The crude benzol formic acid hot filtrate that then previous step is obtained injects cooling pool and naturally cools to 30 ℃ of crystallizations 24 hours, obtains the crude benzol formic acid filter residue and the aqueous solution after the filtration.Adopt storng-acid cation exchange resin to carry out ion exchange treatment the aqueous solution and extract Co, Mn catalyzer.Remaining water reclaims recycling after extracting Co, Mn catalyzer
The crude benzol formic acid filter residue that then previous step is obtained injects the sintering still and is heated to 100 ℃, and constant temperature 25 minutes after confirming to dissolve fully, is put into a receiving plate cooling recrystallize while hot, removes the upper strata stillness of night, obtains bulk crude benzol formic acid.
The bulk crude benzol formic acid that at last previous step is obtained joins in the rectifying tower and heats, and under normal pressure water vapor is steamed earlier, and the water vapor water of generation absorbs; Treat water vapor after rolling, change phenylformic acid rectifying state over to, obtain the technical grade phenylformic acid 1308KG of content 99.05% through the caloic exchange separation of rectifying tower filler gas-liquid from cat head.
Embodiment three
At first from the CTA residue of 5000KG, get three parts of samples, the benzoic acid content that records in the CTA residue is about 30%, according to the benzoic acid content that measures CTA residue and water were made into slurry by weight 1: 5, be invested in and be heated to 100 ℃ in the dissolution kettle, behind the constant temperature 20 minutes, filtered while hot obtains nitration mixture filter cake and crude benzol formic acid hot filtrate.The nitration mixture filter cake that obtains is collected pack, and the main component of nitration mixture filter cake is terephthalic acid, m-phthalic acid and inclined to one side three benzene tricarboxylic acids, can be directly as the raw material of producing unsaturated polyester, softening agent.
The crude benzol formic acid hot filtrate that then previous step is obtained injects cooling pool and naturally cools to 36 ℃ of crystallizations 24 hours, obtains the crude benzol formic acid filter residue and the aqueous solution after the filtration.Adopt storng-acid cation exchange resin to carry out ion exchange treatment the aqueous solution and extract Co, Mn catalyzer.Remaining water reclaims recycling after extracting Co, Mn catalyzer.
The crude benzol formic acid filter residue that then previous step is obtained injects the sintering still and is heated to 100 ℃, and constant temperature 30 minutes after confirming to dissolve fully, is put into a receiving plate cooling recrystallize while hot, removes the upper strata stillness of night, obtains bulk crude benzol formic acid.
The bulk crude benzol formic acid that at last previous step is obtained joins in the rectifying tower and heats, and under normal pressure water vapor is steamed earlier, and the water vapor water of generation absorbs; Treat water vapor after rolling, change phenylformic acid rectifying state over to, obtain the technical grade phenylformic acid 1007KG of content 99.12% through the caloic exchange separation of rectifying tower filler gas-liquid from cat head.
Above-mentioned only is several embodiment of the present invention, but design concept of the present invention is not limited thereto, and allly utilizes this design that the present invention is carried out the change of unsubstantiality, all should belong to the behavior of invading protection domain of the present invention.
Claims (6)
1, the dissolution processing method of CTA residue during PTA produces, described CTA residue mainly comprises phenylformic acid, terephthalic acid, m-phthalic acid, phthalic acid, other organic substances and Co, Mn catalyzer etc., it is characterized in that this dissolution processing method comprises the steps:
1) CTA residue and water are made into slurry, are invested in and are heated to 95～100 ℃ in the dissolution kettle, constant temperature 15～20 minutes, filtered while hot obtains nitration mixture filter cake and crude benzol formic acid hot filtrate;
2) the crude benzol formic acid hot filtrate that obtains is injected cooling pool and naturally cool to 30～40 ℃ of crystallizations, obtain the crude benzol formic acid filter residue and the aqueous solution after the filtration;
3) the crude benzol formic acid filter residue injection sintering still that obtains is heated to 95～100 ℃ and dissolves fully, put into a receiving plate cooling recrystallize and obtain bulk crude benzol formic acid;
4) the bulk crude benzol formic acid that obtains is joined in the rectifying tower heat, under normal pressure water vapor is steamed earlier, the water vapor water of generation absorbs; Treat water vapor after rolling, change phenylformic acid rectifying state over to, the caloic exchange separation of process rectifying tower filler gas-liquid obtains content from cat head and is not less than 99% technical grade phenylformic acid;
5) with step 2) in the aqueous solution that obtains adopt storng-acid cation exchange resin to carry out ion exchange treatment to extract Co, Mn catalyzer.
2, the dissolution processing method of CTA residue during PTA produces according to claim 1, it is characterized in that: the main component of described nitration mixture filter cake is terephthalic acid, m-phthalic acid and inclined to one side three benzene tricarboxylic acids, can be directly as the raw material of producing unsaturated polyester, softening agent.
3, the dissolution processing method of CTA residue during PTA produces according to claim 1, it is characterized in that: crystallisation by cooling is 24 hours described step 2).
4, the dissolution processing method of CTA residue during PTA produces according to claim 1, it is characterized in that: before carrying out step 1), at first gather CTA residue sample and measure benzoic acid content, determine the concentration proportioning of CTA residue and water according to benzoic acid content in the CTA residue that records.
5, the dissolution processing method of CTA residue is characterized in that: the crude benzol formic acid filter residue moisture 60～70% that obtains described step 2) during PTA produced according to claim 1.
6, the dissolution processing method of CTA residue during PTA produces according to claim 1 is characterized in that: water remaining behind the extraction with aqueous solution Co in the step 5), the Mn catalyzer is reclaimed recycling.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101870648A (en) * | 2010-05-28 | 2010-10-27 | 南京万博丰环保科技有限公司 | Method for recovering benzoic acid from PTA oxidation residue |
| CN102381963A (en) * | 2011-08-04 | 2012-03-21 | 绍兴县金程针纺有限公司 | Method and device for preparing benzoic acid by utilizing waste PX (paraxylene) oxidation residues |
| CN102698675A (en) * | 2012-06-20 | 2012-10-03 | 苏州龙峰钛镍设备有限公司 | Recovery tower and recovery process for benzoic acid in pure terephthalic acid (PTA) residues |
| CN102863330A (en) * | 2012-09-29 | 2013-01-09 | 仪征市茂瑞化工有限公司 | Method for separating and refining industrial benzoic acid from PTA (pure terephthalic acid) process wastewater |
| CN105693500A (en) * | 2016-01-18 | 2016-06-22 | 福建洋屿环保科技股份有限公司 | Method for recycling benzoic acid and crude terephthalic acid from PTA oxidation residues |
Family Cites Families (3)
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| CN1253942A (en) * | 1998-11-12 | 2000-05-24 | 韦士平 | Method for recovering benzoic acid from cobalt manganese residue discharged in the course of production of terephthalic acid |
| CN1332145A (en) * | 2001-08-07 | 2002-01-23 | 扬子石油化工股份有限公司 | Benzoic acid recovering process for terephthalic acid oxygenating residue |
| CN1796010A (en) * | 2004-12-29 | 2006-07-05 | 中国石化集团天津石油化工公司 | Method for synthetic using oxidation residue of para-xylene |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101870648A (en) * | 2010-05-28 | 2010-10-27 | 南京万博丰环保科技有限公司 | Method for recovering benzoic acid from PTA oxidation residue |
| CN101870648B (en) * | 2010-05-28 | 2013-11-20 | 南京万博丰环保科技有限公司 | Method for recovering benzoic acid from PTA oxidation residue |
| CN102381963A (en) * | 2011-08-04 | 2012-03-21 | 绍兴县金程针纺有限公司 | Method and device for preparing benzoic acid by utilizing waste PX (paraxylene) oxidation residues |
| CN102698675A (en) * | 2012-06-20 | 2012-10-03 | 苏州龙峰钛镍设备有限公司 | Recovery tower and recovery process for benzoic acid in pure terephthalic acid (PTA) residues |
| CN102863330A (en) * | 2012-09-29 | 2013-01-09 | 仪征市茂瑞化工有限公司 | Method for separating and refining industrial benzoic acid from PTA (pure terephthalic acid) process wastewater |
| CN105693500A (en) * | 2016-01-18 | 2016-06-22 | 福建洋屿环保科技股份有限公司 | Method for recycling benzoic acid and crude terephthalic acid from PTA oxidation residues |
| CN105693500B (en) * | 2016-01-18 | 2019-07-26 | 福建洋屿环保科技股份有限公司 | A method of recovery of benzoic acid and crude terephthalic acid from PTA oxidation residua |
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