CN111099991A - Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost - Google Patents
Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost Download PDFInfo
- Publication number
- CN111099991A CN111099991A CN201911414587.XA CN201911414587A CN111099991A CN 111099991 A CN111099991 A CN 111099991A CN 201911414587 A CN201911414587 A CN 201911414587A CN 111099991 A CN111099991 A CN 111099991A
- Authority
- CN
- China
- Prior art keywords
- dicarboxylic acid
- water
- crystallization
- carbon chain
- chain dicarboxylic
- 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.)
- Pending
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 144
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 title claims abstract description 124
- 238000000034 method Methods 0.000 title claims abstract description 103
- 238000007670 refining Methods 0.000 title claims abstract description 61
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims abstract description 267
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 171
- 238000002425 crystallisation Methods 0.000 claims abstract description 133
- 230000008025 crystallization Effects 0.000 claims abstract description 133
- 239000012065 filter cake Substances 0.000 claims abstract description 87
- 239000002904 solvent Substances 0.000 claims abstract description 70
- 238000001914 filtration Methods 0.000 claims abstract description 66
- 239000012452 mother liquor Substances 0.000 claims abstract description 52
- 239000000047 product Substances 0.000 claims abstract description 51
- 238000001035 drying Methods 0.000 claims abstract description 45
- 239000002994 raw material Substances 0.000 claims abstract description 24
- 239000012043 crude product Substances 0.000 claims abstract description 20
- 238000010533 azeotropic distillation Methods 0.000 claims abstract description 19
- 238000001953 recrystallisation Methods 0.000 claims abstract description 16
- 239000002253 acid Substances 0.000 claims abstract description 14
- DCKVNWZUADLDEH-UHFFFAOYSA-N sec-butyl acetate Chemical group CCC(C)OC(C)=O DCKVNWZUADLDEH-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000001816 cooling Methods 0.000 claims description 95
- 238000005406 washing Methods 0.000 claims description 92
- 238000002386 leaching Methods 0.000 claims description 69
- -1 carbon chain dicarboxylic acids Chemical class 0.000 claims description 60
- 239000000706 filtrate Substances 0.000 claims description 57
- 239000013078 crystal Substances 0.000 claims description 56
- 230000008569 process Effects 0.000 claims description 56
- 238000003756 stirring Methods 0.000 claims description 51
- 238000000926 separation method Methods 0.000 claims description 46
- 239000008367 deionised water Substances 0.000 claims description 39
- 229910021641 deionized water Inorganic materials 0.000 claims description 39
- 239000003712 decolorant Substances 0.000 claims description 35
- 239000007788 liquid Substances 0.000 claims description 31
- 239000000498 cooling water Substances 0.000 claims description 26
- 238000005185 salting out Methods 0.000 claims description 22
- 239000000463 material Substances 0.000 claims description 20
- 238000000746 purification Methods 0.000 claims description 15
- 238000000855 fermentation Methods 0.000 claims description 14
- 230000004151 fermentation Effects 0.000 claims description 14
- 239000011229 interlayer Substances 0.000 claims description 14
- 238000004519 manufacturing process Methods 0.000 claims description 14
- 238000010438 heat treatment Methods 0.000 claims description 13
- 238000004064 recycling Methods 0.000 claims description 12
- 239000002002 slurry Substances 0.000 claims description 12
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 238000004042 decolorization Methods 0.000 claims description 9
- 238000003860 storage Methods 0.000 claims description 7
- 239000010410 layer Substances 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 5
- 238000004090 dissolution Methods 0.000 claims description 4
- 238000004821 distillation Methods 0.000 claims description 4
- 230000000813 microbial effect Effects 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 3
- 238000010923 batch production Methods 0.000 claims description 2
- LHFQJLUDFHACLD-UHFFFAOYSA-N butan-2-yl acetate hydrate Chemical compound O.CCC(C)OC(C)=O LHFQJLUDFHACLD-UHFFFAOYSA-N 0.000 claims description 2
- 238000009833 condensation Methods 0.000 claims description 2
- 230000005494 condensation Effects 0.000 claims description 2
- 150000001991 dicarboxylic acids Chemical class 0.000 claims description 2
- 239000000284 extract Substances 0.000 claims description 2
- 239000012188 paraffin wax Substances 0.000 claims 1
- 239000003795 chemical substances by application Substances 0.000 abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract 1
- 229910052757 nitrogen Inorganic materials 0.000 abstract 1
- SNRUBQQJIBEYMU-UHFFFAOYSA-N Dodecane Natural products CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 19
- 239000004677 Nylon Substances 0.000 description 17
- 229920001778 nylon Polymers 0.000 description 17
- 238000001556 precipitation Methods 0.000 description 7
- 239000006227 byproduct Substances 0.000 description 6
- 230000009467 reduction Effects 0.000 description 5
- 239000012535 impurity Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 239000000853 adhesive Substances 0.000 description 3
- 230000001070 adhesive effect Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- 239000004014 plasticizer Substances 0.000 description 3
- WMRCTEPOPAZMMN-UHFFFAOYSA-N 2-undecylpropanedioic acid Chemical compound CCCCCCCCCCCC(C(O)=O)C(O)=O WMRCTEPOPAZMMN-UHFFFAOYSA-N 0.000 description 2
- 239000004831 Hot glue Substances 0.000 description 2
- 150000001335 aliphatic alkanes Chemical class 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- TVIDDXQYHWJXFK-UHFFFAOYSA-N dodecanedioic acid Chemical compound OC(=O)CCCCCCCCCCC(O)=O TVIDDXQYHWJXFK-UHFFFAOYSA-N 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- 238000005461 lubrication Methods 0.000 description 2
- 239000010413 mother solution Substances 0.000 description 2
- 238000006068 polycondensation reaction Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 241000222120 Candida <Saccharomycetales> Species 0.000 description 1
- JHWNWJKBPDFINM-UHFFFAOYSA-N Laurolactam Chemical compound O=C1CCCCCCCCCCCN1 JHWNWJKBPDFINM-UHFFFAOYSA-N 0.000 description 1
- ALHUZKCOMYUFRB-OAHLLOKOSA-N Muscone Chemical compound C[C@@H]1CCCCCCCCCCCCC(=O)C1 ALHUZKCOMYUFRB-OAHLLOKOSA-N 0.000 description 1
- 229920000571 Nylon 11 Polymers 0.000 description 1
- 229920000299 Nylon 12 Polymers 0.000 description 1
- 229920000572 Nylon 6/12 Polymers 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 125000002015 acyclic group Chemical group 0.000 description 1
- 125000004442 acylamino group Chemical group 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 125000003368 amide group Chemical group 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 150000004985 diamines Chemical class 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 229940057995 liquid paraffin Drugs 0.000 description 1
- 239000003879 lubricant additive Substances 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 230000009456 molecular mechanism Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- ALHUZKCOMYUFRB-UHFFFAOYSA-N muskone Natural products CC1CCCCCCCCCCCCC(=O)C1 ALHUZKCOMYUFRB-UHFFFAOYSA-N 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002304 perfume Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000005504 petroleum refining Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 229920006122 polyamide resin Polymers 0.000 description 1
- 229920001707 polybutylene terephthalate Polymers 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- 229920013636 polyphenyl ether polymer Polymers 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
- C07C51/44—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation by distillation
- C07C51/46—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation by distillation by azeotropic distillation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/47—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for refining and purifying long carbon chain dicarboxylic acid with high yield and low cost, which comprises the following steps of ①, wherein the raw material for refining and purifying the long chain dicarboxylic acid crude product does not need drying treatment, ② decoloration agent filter cake obtained after decoloration and filtration is washed by solvent acetic acid, ③, before the solvent is recovered, the recrystallization mother liquor is first elutriated and crystallized, the long carbon chain dicarboxylic acid product dissolved in the crystallization mother liquor is extracted again, ④, the solvent in the filtration mother liquor after elutriation and crystallization is recovered, and the method is characterized in thatThe azeotropic distillation method is adopted, and the azeotropic agent is sec-butyl acetate. The refined and purified long carbon chain dicarboxylic acid reaches the following technical indexes: more than or equal to 99.30 wt% of monoacid, more than or equal to 99.80 wt% of total acid, less than or equal to 15ppm of ash, Fe as Fe2O3Less than or equal to 1ppm, less than or equal to 15ppm of total nitrogen calculated by N element and less than or equal to 0.2 wt% of water; the refining and purifying yield of the long carbon chain dicarboxylic acid is more than or equal to 96.00 percent.
Description
Technical Field
The invention relates to a method for refining and purifying long carbon chain dicarboxylic acid with high yield and low cost. Belonging to the purification treatment of acyclic dicarboxylic acid with more than 10 carbon atoms.
Background
Long-carbon chain dicarboxylic acid (straight-chain dicarboxylic acid) with a carbon chain containing more than 10 carbon atoms is an important fine chemical product. It is used as main material for synthesizing polyamide resin, polyester resin, hot melt adhesive, perfume, weather resisting plasticizer, lubricant additive, paint, liquid crystal, etc.
The main industrial applications include the artificial synthesis of muscone; coil adhesives used at 100 ℃ for a long time; hot-melt adhesive for shaping clothes; not only can be used for manufacturing a high-temperature-resistant lubricant, but also can be used for manufacturing a lubricant which can realize effective lubrication at a low temperature of minus 45 ℃; the high-performance paint prepared from the long carbon chain dibasic acid has the characteristics of bright color, good wear resistance, high impact strength, strong adhesive force, good flexibility, long-time ultraviolet irradiation resistance and the like. It is suitable for use as paint for sedan, luxurious furniture, national defense tent, military combat and transport means. The long carbon chain dibasic acid can also synthesize the plasticizer with excellent cold resistance, and the plastic film manufactured by adding the plasticizer can be used for a long time in a cold environment.
Nylon is a kind of high molecular compound whose molecular main chain contains amide group (-NHCO-). The nylon molecular structure contains a large amount of acylamino, and the tail end of a macromolecule is amino or carboxyl, so that the nylon is a crystalline polymer which has strong polarity, can form hydrogen bonds among molecules and has certain reaction activity. The nylon is one of five engineering plastics (nylon, polyformaldehyde, polycarbonate, polyphenyl ether and polybutylene terephthalate) with the largest consumption, the largest variety, the widest application and the oldest qualification,
the molecular mechanism of long-chain nylon endows the long-chain nylon with good comprehensive performance, the strength is higher than that of metal, the mechanical performance, the heat resistance, the wear resistance, the chemical resistance, the flame retardance and the self-lubrication are excellent, the friction coefficient is low, the processing is easy, and the long-chain nylon can be processed into various plastic products, also can be drawn into fibers, and also can be processed into films, coatings, adhesives and the like. The method is widely applied to the fields of automobiles, electronics, electrics, machinery, communication, military, aerospace and the like.
Long carbon chain nylon synthesized by using long carbon chain dicarboxylic acid as a raw material and performing polycondensation reaction between a polycondensation monomer and diamine mainly comprises nylon 11, nylon 12, nylon 612, nylon 1111, nylon 1112, nylon 1212, nylon 1213, nylon 1314, nylon 1414, nylon 512, nylon 614 and the like.
The long carbon chain dicarboxylic acid does not exist in the nature, is mainly prepared by an organic synthesis method and a biological fermentation method, and has the advantages of long process route, high cost, low yield, potential safety hazard and environmental pollution.
The biological fermentation method mainly comprises the following steps of11～C18Normal alkane is used as a raw material, and is fermented by candida to convert monoalkyl into long-chain dibasic acid, and then the long-chain dibasic acid is obtained by crude purification and refining. The n-alkane is distilled from petroleum refining and contains C11～C18The component (A) is a by-product obtained by degreasing petroleum by adopting a urea process, and is commonly called liquid paraffin. Therefore, the long-chain dicarboxylic acid produced by the method has the advantages of wide raw material source, simple production process, small investment and low production cost. Therefore, most of the long carbon chain dibasic acids sold in the market at present are products produced by a biological fermentation method.
The purity and appearance of the product are seriously affected because the fermentation product contains a small amount of impurities such as mycoprotein, pigment, iron ion compounds and the like. Therefore, the refining and purifying process is a crucial link for preparing the long carbon chain dicarboxylic acid by microbial fermentation.
The long carbon chain dicarboxylic acid produced by the microbial fermentation method is purified and refined by recrystallization mainly by a solvent method. The solvent mainly adopts acetic acid, methanol and the like. Tests and production practices show that acetic acid is superior to other organic solvents in refining time, refining solvent consumption and purity of crystallized products.
In the prior art, a long-chain dicarboxylic acid crude product prepared by a fermentation method is used as a raw material, acetic acid is used as a solvent, the long-chain dicarboxylic acid product is prepared by recrystallization refining and purifying, decoloring, filtering, cooling, crystallizing, centrifuging, washing a filter cake and drying, and after a crystallization mother liquor is subjected to solvent recovery, an obtained heavy component is repeatedly recycled and reused as a refining and purifying raw material. Or as a raw material for preparing mixed long carbon chain dicarboxylic acid.
The prior art has the following defects:
1. in the prior art, a crude product with the water content of 20-25 wt% is used as a refined raw material. The drying equipment is saved, the operation steps are simplified, and the production cost is reduced. However, the water carried by the crude raw material reduces the solubility of the refined and purified long carbon chain dicarboxylic acid in an acetic acid solvent, so that part of the long carbon chain dicarboxylic acid crystals enter a filter cake along with activated carbon, the dicarboxylic acid loss is caused, and the refining and purifying yield of the dicarboxylic acid is reduced.
2. After the crystallization mother liquor is subjected to solvent recovery, the obtained heavy component is used as a refined purification raw material to be repeatedly recovered and reused, so that other mixed dibasic acid and other impurities generated in the fermentation process are accumulated, and the quality of the long carbon chain dicarboxylic acid product is influenced.
3. And recovering the solvent from the crystallization mother liquor, and using the obtained heavy component as a raw material for preparing the mixed long carbon chain dicarboxylic acid. Leading the main product of the target dicarboxylic acid dissolved in the crystallization mother liquor to be produced and sold as a long carbon chain mixed dicarboxylic acid by-product. The grade and the economic benefit of the target long carbon chain dicarboxylic acid main product contained in the product are reduced. Meanwhile, the yield of the refined target long carbon chain dicarboxylic acid main product is reduced.
The main component in the crystallization mother liquor is solvent acetic acid, long carbon chain dicarboxylic acid which can not be crystallized and still dissolved in the mother liquor, and a small amount of water and other impurities. Usually, the mixed long-chain dicarboxylic acid is contained in an amount of about 4 to 6 wt%, wherein the purified long-chain dicarboxylic acid (also referred to as a main product or a target product) accounts for about 90 to 95% of the total mass of the mixed long-chain dicarboxylic acid dissolved in the crystallization mother liquor, and the mixed long-chain dicarboxylic acid by-produced in addition to the target product long-chain dicarboxylic acid accounts for about 5 to 10% of the total mass of the long-chain dicarboxylic acid dissolved in the crystallization mother liquor.
4. In the prior art, a conventional distillation method is adopted for recovering a solvent in a mother solution, the mother solution at the bottom of a distillation kettle is continuously concentrated, thickened and deteriorated along with the rise of the temperature, part of materials are carbonized, and the color is darkened. In addition to the reduction of the recovery yield of the by-products, the difficulty of the subsequent decoloring purification treatment process is increased, or even the quality of the by-products is adversely affected.
Like all chemical products, the improvement of the refining and purifying yield and the reduction of the production cost are the constant subjects of the long carbon chain dicarboxylic acid refining and purifying industry. It would be desirable to provide a purification process for long carbon chain dicarboxylic acids with high yield and low cost.
Disclosure of Invention
The invention aims to avoid the defects in the prior art and provides the method for refining and purifying the long carbon chain dicarboxylic acid, which has high product yield, lower refining cost and high purity.
The object of the invention can be achieved by the following measures:
the invention relates to a refining and purifying method of long carbon chain dicarboxylic acid with high yield and low cost, which takes a long carbon chain dicarboxylic acid crude product prepared by a fermentation method as a raw material, adopts acetic acid as a solvent, and prepares the long carbon chain dicarboxylic acid product through recrystallization, refining and purifying, decoloring, filtering, cooling, crystallizing, centrifugal separation, filter cake washing and drying process, and heavy components obtained after recrystallization mother liquor recovers the solvent are mixed with the long carbon chain dicarboxylic acid crude product to be recycled as a refining and purifying raw material, and is characterized in that:
①, the raw material long carbon chain dicarboxylic acid crude product for refining and purification directly enters the subsequent decolorization process without drying treatment;
②, washing the decolorant filter cake obtained after decoloration and filtration with a solvent acetic acid, and combining the obtained decolorant filter cake washing liquid and the decolorant filtration filtrate to enter a subsequent cooling crystallization process so as to recover long carbon chain dicarboxylic acid carried in the decolorant activated carbon;
③, before recovering the solvent, the recrystallization mother liquor firstly elutes and crystallizes, and then extracts the long carbon chain dicarboxylic acid product dissolved in the crystallization mother liquor again, wherein the elutriation crystallization is to add deionized water into the crystallization mother liquor to crystallize and separate out the long carbon chain dicarboxylic acid product dissolved in the acetic acid solvent, then the filtration and the separation are carried out, the obtained long carbon chain dicarboxylic acid crystal is combined with the crystal obtained by the first recrystallization, and the combined crystal and the crystal enter the subsequent leaching and drying processes to jointly prepare the long carbon chain dicarboxylic acid product;
④ recovering solvent from the filtered mother liquid after water separation and crystallization, recovering and utilizing by azeotropic distillation, separating water from acetic acid by azeotropic distillation process, using the separated water as water for water separation and crystallization in characteristic ③, and recycling the separated solvent acetic acid as solvent in the process of long carbon chain dicarboxylic acid refining and purification.
The invention has the technical characteristics that ② decolorant filter cakes obtained after decoloration and filtration are washed by solvent acetic acid, the obtained decolorant filter cake washing liquid and decolorant filtration filtrate are combined to enter the subsequent cooling and crystallization process, and long carbon chain dicarboxylic acid carried in decolorant active carbon is successfully recovered, thus making technical contribution to improving the purification yield of refined and purified long carbon chain dicarboxylic acid, simultaneously solving the technical problems that in the prior art, the water carried by crude raw materials reduces the solubility of the refined and purified long carbon chain dicarboxylic acid in the acetic acid solvent, causing partial long carbon chain dicarboxylic acid raw materials to enter the filter cakes along with the active carbon, causing the loss of the long carbon chain dicarboxylic acid, thereby reducing the refining and purifying yield of the refined and purified long carbon chain dicarboxylic acid, leading the raw materials for refining and purifying the long carbon chain dicarboxylic acid crude products not to need to be dried, and directly entering the subsequent decoloration process,
the invention is characterized in that ③ recrystallization mother liquor is firstly crystallized by water precipitation and then the long carbon chain dicarboxylic acid product dissolved in the crystallization mother liquor is extracted again before the solvent is recovered, thereby solving the technical problem that the target dicarboxylic acid main product dissolved in the crystallization mother liquor is totally produced and sold as a long carbon chain mixed dicarboxylic acid byproduct in the prior art.
The invention has the technical characteristics that ④ solvent in the filtered mother liquor after the elutriation and crystallization is recovered and utilized by adopting an azeotropic distillation method, an entrainer adopts sec-butyl acetate, water and acetic acid are separated by an azeotropic distillation process, the separated water is used as feed water for the elutriation and crystallization in the characteristic ③ and is recycled, and the separated solvent acetic acid is used as the solvent for recycling in the refining and purifying process of the long carbon chain dicarboxylic acid.
The object of the invention is also achieved by the following measures:
the invention discloses a refining and purifying method of long carbon chain dicarboxylic acid with high yield and low cost, wherein the long carbon chain dicarboxylic acid is C11～C18A straight chain saturated dicarboxylic acid.
The invention relates to a method for refining and purifying long carbon chain dicarboxylic acid with high yield and low cost, wherein ① item of crude long carbon chain dicarboxylic acid to be refined takes long carbon chain normal alkane as a raw material, fermentation liquor prepared by microbial fermentation is filtered, decolored, acidified, crystallized and filtered to obtain filter cake crystals, the water content of the filter cake crystals is less than or equal to 20 wt%, and the filter cake crystals are directly used as refining raw materials without drying.
The invention discloses a method for refining and purifying long carbon chain dicarboxylic acid with high yield and low cost, wherein ②, a decolorant filter cake obtained after decoloration and filtration is washed by solvent acetic acid, and the washing is carried out by using industrial acetic acid with the solvent acetic acid content of more than or equal to 95 wt% or recycling acetic acid, which is a preferable technical scheme.
The method for refining and purifying the long carbon chain dicarboxylic acid with high yield and low cost is characterized in that a decolorizer filter cake obtained after the decolorization and filtration in item ② is washed by solvent acetic acid, and the solvent acetic acid for washing is hot acetic acid with the temperature of 80-95 ℃, and is a preferable technical scheme.
The invention relates to a refining and purifying method of long carbon chain dicarboxylic acid with high yield and low cost, wherein ③ the elutriation and crystallization process comprises the steps of firstly adding deionized water into crystallization mother liquor under stirring, controlling the volume ratio of the mother liquor to the deionized water to be 1: 0.5-1, elutriating and crystallizing for 30-60 minutes under stirring to crystallize and separate out a long carbon chain dicarboxylic acid product dissolved in an acetic acid solvent, then filtering and separating by using a plate and frame filter press, combining the long carbon chain dicarboxylic acid crystal with the filter cake content of 65-80 wt% obtained in the filter press with the crystal obtained by the first recrystallization, and carrying out subsequent leaching and drying steps to jointly prepare a main long carbon chain dicarboxylic acid product.
According to the method for refining and purifying the long carbon chain dicarboxylic acid, which is high in yield and low in cost, in the elutriation and crystallization process of item ③, deionized water added into crystallization mother liquor is water-phase leaching filtrate generated in the water-phase leaching step in the long carbon chain dicarboxylic acid refining and purifying process, and the method is a preferable technical scheme.
The invention relates to a long carbon chain dicarboxylic acid refining and purifying method with high yield and low cost, which is characterized in that solvent in filtered mother liquor after water precipitation and crystallization in item ④ is recovered, and the operation method of the azeotropic distillation process is as follows:
the method comprises the steps of enabling filtered mother liquor after water separation crystallization treatment to enter an azeotropic distillation system, enabling an entrainer to be sec-butyl acetate preferably, collecting sec-butyl acetate-water azeotrope from the top of a distillation process tower at 85-95 ℃ in a gas phase mode, enabling the azeotrope to enter a phase splitter for layering after condensation, collecting a lower-layer water phase as water for water separation crystallization feeding in ① for recycling, enabling an upper-layer sec-butyl acetate phase to flow back to an azeotropic distillation kettle to participate in azeotropic distillation continuously, enabling the temperature of the upper-layer sec-butyl acetate phase to be controlled at 110-125 ℃ to collect acetic acid, collecting the acetic acid with the content being more than or equal to 95 wt% after cooling and heating, enabling the acetic acid to be used as an acetic acid solvent for recycling at a long-carbon-chain binary acid crude product dissolution and decoloration working section, and controlling the material temperature of the azeotropic distillation kettle.
The method for refining and purifying the long carbon chain dicarboxylic acid with high yield and low cost is characterized by comprising the following operation steps:
first step, dissolving and decolorizing
At room temperature, putting a crude long carbon chain dicarboxylic acid crude product with the water content of less than or equal to 20 wt%, acetic acid and activated carbon into a decoloring reaction kettle, heating the materials in the decoloring reaction kettle to 90-95 ℃ under stirring, preserving the temperature for 10-30 minutes, filtering, performing solid-liquid separation, and feeding the filtrate into a crystallization kettle for crystallization; washing a decolorant filter cake obtained after decoloration and filtration by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 80-95 ℃, sending the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover long carbon chain dicarboxylic acid carried in decolorant activated carbon;
second, cooling and crystallizing
Putting the filtrate decolored in the first step into a crystallization kettle, and carrying out gradient cooling crystallization under stirring:
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, and cooling the decolorized filtrate from step ① to 75-80 ℃;
② two-stage cooling and induced crystallization
Stirring, naturally cooling to 71-75 ℃, adding long carbon chain dibasic acid to induce seed crystal, and then continuously naturally cooling to 68-70 ℃;
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, and cooling the temperature of the crystallization feed liquid to 20-30 ℃ until the crystallization is complete;
④, centrifuging and filtering;
centrifuging and filtering the completely crystallized material from item ③, washing the filter cake, and separating out the crystal from the mother liquor;
third step, water precipitation crystallization
Putting the mother liquor generated by centrifugal filtration in the second step ④ into a water precipitation crystallization kettle, adding deionized water under stirring, or adding water phase leaching filtrate generated in the water phase leaching process in the fourth step ②, wherein the addition amount of the water phase leaching filtrate is controlled to be 1: 0.5-1, heating to 85-95 ℃ under stirring, then cooling to 25-30 ℃, performing water precipitation crystallization for 30-60 minutes, crystallizing and separating out a long carbon chain dicarboxylic acid product dissolved in an acetic acid solvent, then performing filtration and separation by using a plate and frame filter press, mixing the long carbon chain dicarboxylic acid crystal with the filter cake content of 65-80 wt% obtained in the filter press with the crystal obtained by cooling and crystallization in the second step, and performing subsequent washing and drying steps together to obtain a long carbon chain dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Crystallizing the long carbon chain dicarboxylic acid after the centrifugal separation in the second step and the third step, leaching in a centrifugal machine by using a small amount of acetic acid, wherein the leaching amount of the acetic acid is 5-100% of that of the acetic acid for dissolution and decoloration in the first step; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Washing the filter cake in the centrifuge with deionized water or room temperature water washing filtrate generated in the subsequent ③ items, centrifuging and spin-drying again, and washing the filter cake with room temperature water;
③ washing with water at room temperature, and centrifuging
The filter cake from item ② is made into slurry by deionized water and then is sent into a water washing tank, the deionized water accounts for 70-120 percent of the mass of acetic acid used in the dissolving and decoloring step in the first step, the mixture is stirred and washed for 30 minutes in the water washing tank, centrifugal filtration is carried out, solid-liquid separation is carried out, the filter cake is ready for drying, the room-temperature water washing filtrate is sent into a room-temperature water washing filtrate storage tank and is ready for being used as water for water phase leaching in item ② in the fourth step of next batch production for recycling;
⑤ drying
And (3) drying the filter cake from the ③ item to obtain refined long carbon chain dicarboxylic acid, wherein the refined and purified long carbon chain dicarboxylic acid achieves the following technical indexes:
the refining and purifying yield of the long carbon chain dicarboxylic acid is more than or equal to 96.00 percent.
Compared with the prior art, the technical scheme disclosed by the method for refining and purifying the long carbon chain dicarboxylic acid with high yield and low cost can produce the following positive effects:
1. provides a refining and purifying method of long carbon chain dicarboxylic acid with high product yield, lower refining cost and high purity.
2. The method avoids the defects that in the prior art, after the crystallization mother liquor is subjected to solvent recovery, the obtained heavy component is repeatedly recycled and reused as a refined and purified raw material, so that the accumulation of other mixed dibasic acid and other impurities generated in the fermentation process affects the quality of the long-carbon-chain dicarboxylic acid product.
3. Washing the decolorant filter cake obtained after decoloration and filtration with a solvent acetic acid, combining the obtained decolorant filter cake washing liquid and the decolorant filtration filtrate, and entering a subsequent cooling and crystallization process, thereby successfully recovering the long carbon chain dicarboxylic acid carried in the decolorant activated carbon. The technical scheme that the raw material long-chain dibasic acid crude product for refining and purification directly enters the subsequent decoloring technological process without drying treatment is implemented, and the problem that the dicarboxylic acid loss is caused by the fact that long-carbon-chain dibasic acid crystals enter a filter cake along with activated carbon in the prior art, and thus the dicarboxylic acid refining and purification yield is reduced is solved.
4. Before the solvent is recovered from the recrystallization mother liquor, the recrystallization mother liquor is first water-separated for crystallization, and the long carbon chain dicarboxylic acid product dissolved in the crystallization mother liquor is extracted again. Solves the technical problem that the target dicarboxylic acid main product dissolved in the crystallization mother liquor is completely produced and sold as the long carbon chain mixed dicarboxylic acid by-product in the prior art.
5. The method comprises the steps of recovering a solvent in a filtered mother liquor after water separation crystallization, recycling the solvent by adopting an azeotropic distillation method, selecting sec-butyl acetate as an entrainer, separating water from acetic acid through an azeotropic distillation process, using the separated water as water for water separation crystallization feeding in characteristic ③, recycling the water, and using the separated solvent acetic acid as the solvent in a refining and purifying process of long carbon chain dicarboxylic acid.
6. The refined and purified long carbon chain dicarboxylic acid reaches the following technical indexes:
the refining and purifying yield of the long carbon chain dicarboxylic acid is more than or equal to 96.00 percent.
Detailed Description
The invention will be further described in detail with reference to the following examples:
example 1 a method for refining and purifying dodecanedicarboxylic acid with high yield and low cost according to the present invention comprises the following steps:
first step, dissolving and decolorizing
Putting 1000Kg of a crude product of the dodecanedicarboxylic acid with the mass percentage of 80 percent, 2000L of 95wt percent industrial acetic acid and 6Kg of activated carbon into a decoloring reaction kettle at room temperature, heating the materials in the decoloring kettle to 95 ℃ under stirring, preserving the temperature for 20 minutes, filtering, performing solid-liquid separation, and sending the filtrate into a crystallization kettle for crystallization; and (3) washing a decolorant filter cake obtained after decoloring and filtering by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 80 ℃, feeding the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover the dodecyl dicarboxylic acid carried in the decolorant activated carbon.
Second, cooling and crystallizing
And (3) putting the filtrate subjected to the first-step decolorization into a crystallization kettle, stirring, and performing gradient cooling crystallization.
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, cooling the decolorized filtrate from the first step to 78 ℃, and closing the cooling water.
② two-stage cooling and induced crystallization
Naturally cooling to 75 ℃ under stirring, adding dodecyl dicarboxylic acid with the purity of more than 99.8 percent as seed crystal, controlling the stirring speed to be 40r/min, rebounding the temperature in the crystallization kettle to be 77 ℃, and then gradually reducing. The temperature naturally dropped to 68 ℃.
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, controlling the cooling speed from slow to fast, and finally cooling to 25 ℃ until the crystallization is complete.
The whole cooling crystallization time is controlled to be 6-8 hours.
④, centrifuging and filtering;
the completely crystallized material from item ③ above was centrifuged, the cake was rinsed, and the mother liquor was crystallized by water precipitation.
Third step, water precipitation crystallization
Putting the mother liquor generated by the centrifugal filtration in the second step ④ into a water precipitation crystallization kettle, adding 2000L of deionized water, stirring, heating to 85 ℃, then cooling to 25 ℃, performing water precipitation crystallization for 30-60 minutes to separate out the crystals of the dodecyl dicarboxylic acid product dissolved in the acetic acid solvent, filtering and separating by using a plate and frame filter press, mixing the 102.28Kg of filter cake obtained in the filter press with the crystals obtained by the temperature reduction crystallization in the second step, and performing subsequent washing and drying steps to jointly prepare the dodecyl dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Merging the dodecyl dicarboxylic acid crystals after the centrifugal separation in the second step and the third step, leaching in a centrifuge by 200L of 98 wt% acetic acid, and centrifuging for 15 minutes after leaching; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Leaching a filter cake in a centrifuge by 2000L of deionized water, centrifuging and drying for 15 minutes, and washing the filter cake at room temperature; sending the water-phase leaching filtrate generated in the water-phase leaching process into a water-phase leaching filtrate storage tank for use in place of deionized water in the third step of a water separation crystallization process;
③ washing with water at room temperature, and centrifuging
Making 1200L of deionized water into slurry from ② filter cakes, sending the slurry into a water washing tank, adding 800L of deionized water into the water washing tank, stirring and washing for 30 minutes, performing centrifugal filtration, performing solid-liquid separation, and drying the filter cakes;
⑤ drying
And drying the filter cake from ③ items to obtain 768Kg of refined dodecyl dicarboxylic acid, wherein the refined and purified dodecyl dicarboxylic acid achieves the following technical indexes:
the refining and purifying yield of the dodecyl dicarboxylic acid is 96.00 percent.
Example 2. the refining and purifying method of dodecanedioic acid of the invention with high yield and low cost comprises the following steps:
first step, dissolving and decolorizing
At room temperature, 940Kg of a crude dodecyl dicarboxylic acid product with the mass percentage of 80.8 percent of dodecyl dicarboxylic acid, 200L of a centrifugate generated in the process of washing ① acetic acid by using crystals in the step 4 of the embodiment 1, 1800L of 95wt percent of industrial acetic acid and 6Kg of active carbon are put into a decoloring reaction kettle, materials in the decoloring kettle are heated to 90 ℃ under stirring, the temperature is kept for 30 minutes, the materials are filtered, solid-liquid separation is carried out, filtrate is sent into a crystallization kettle for crystallization, a decoloring agent filter cake obtained after decoloring and filtering is washed by hot acetic acid with the content of more than or equal to 95wt percent and the temperature of 95 ℃, the obtained decoloring agent filter cake washing liquid is also sent into the crystallization kettle, and the decoloring agent filter cake washing liquid and the decolored filtrate complete the subsequent cooling and crystallizing process together to recover the dodecyl dicarboxylic acid carried in the.
Second, cooling and crystallizing
And (3) putting the filtrate subjected to the first-step decolorization into a crystallization kettle, stirring, and performing gradient cooling crystallization.
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, cooling the decolorized filtrate from the first step to 77 ℃, and closing the cooling water.
② two-stage cooling and induced crystallization
Naturally cooling to 73 ℃ under stirring, adding dodecyl dicarboxylic acid with the purity of more than 99.8 percent as seed crystal, controlling the stirring speed to be 40r/min, rebounding the temperature in the crystallization kettle to be 75 ℃, and then gradually reducing. The temperature naturally drops to 70 ℃.
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, controlling the cooling speed from slow to fast, and finally cooling to 30 ℃ until the crystallization is complete.
The whole cooling crystallization time is controlled to be 6-8 hours.
④, centrifuging and filtering;
the completely crystallized material from item ③ above was centrifuged, the cake was rinsed, and the mother liquor was crystallized by water precipitation.
Third step, water precipitation crystallization
Putting the mother liquor generated by centrifugal filtration in the second step ④ into a water precipitation crystallization kettle, adding 2000L of water phase leaching filtrate generated in the water phase leaching process in the fourth step ② in the embodiment 1, heating to 95 ℃ under stirring, then cooling to 30 ℃ for water precipitation crystallization for 30-60 minutes to separate out crystals of a dodecyl dicarboxylic acid product dissolved in an acetic acid solvent, filtering and separating by adopting a plate and frame filter press, combining a filter cake obtained in the filter press, which is 98Kg of dodecyl dicarboxylic acid crystals, with the crystals obtained by cooling and crystallization in the second step, and performing subsequent washing and drying steps to jointly prepare a dodecyl dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Merging the dodecyl dicarboxylic acid crystals after the centrifugal separation in the second step and the third step, leaching in a centrifuge by using 300L of 98 wt% acetic acid, and centrifuging for 15 minutes after leaching; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Washing a filter cake in a centrifuge by 2000L of room-temperature water washing filtrate generated in the fourth step ③ in example 1, centrifuging and spin-drying for 15 minutes, washing the filter cake by room-temperature water, sending water-phase washing filtrate generated in the water-phase washing process into a water-phase washing filtrate storage tank, and using the water-phase washing filtrate in the third step of a water separation crystallization process to replace deionized water;
③ washing with water at room temperature, and centrifuging
Making 1200L of deionized water into slurry from ② filter cakes, sending the slurry into a water washing tank, adding 800L of deionized water into the water washing tank, stirring and washing for 30 minutes, performing centrifugal filtration, performing solid-liquid separation, and drying the filter cakes;
⑤ drying
The filter cake from ③ is dried to obtain 730.66Kg of refined dodecyl dicarboxylic acid, and the refined and purified dodecyl dicarboxylic acid reaches the following technical indexes:
the refining and purifying yield of the dodecyl dicarboxylic acid is 96.20 percent.
Example 3. the refining and purifying method of tetradecyl dicarboxylic acid with high yield and low cost of the present invention comprises the following steps:
first step, dissolving and decolorizing
At room temperature, 805Kg of tetradecyl dicarboxylic acid crude product with 82.0 percent of tetradecyl dicarboxylic acid by mass, 2000L of 95 percent industrial acetic acid by mass and 6Kg of activated carbon are put into a decoloring reaction kettle, materials in the decoloring kettle are heated to 92 ℃ under stirring, the temperature is kept for 10 minutes, filtration and solid-liquid separation are carried out, and filtrate is sent into a crystallization kettle for crystallization; and (3) washing a decolorant filter cake obtained after decoloring and filtering by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 90 ℃, feeding the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover tetradecyl dicarboxylic acid carried in decolorant activated carbon.
Second, cooling and crystallizing
And (3) putting the filtrate subjected to the first-step decolorization into a crystallization kettle, stirring, and performing gradient cooling crystallization.
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, cooling the decolorized filtrate from the first step to 77 ℃, and closing the cooling water.
② two-stage cooling and induced crystallization
Naturally cooling to 71 ℃ under stirring, adding tetradecyl dicarboxylic acid with the purity of more than 99.8 percent as seed crystal, controlling the stirring speed at 40r/min, rebounding the temperature in the crystallization kettle to 72-73 ℃, and then gradually reducing. The temperature naturally dropped to 69 ℃.
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, controlling the cooling speed from slow to fast, and finally cooling to 27 ℃ until the crystallization is complete.
The whole cooling crystallization time is controlled to be 6-8 hours.
④, centrifuging and filtering;
the completely crystallized material from item ③ above was centrifuged, the cake was rinsed, and the mother liquor was crystallized by water precipitation.
Third step, water precipitation crystallization
Putting the mother liquor generated by the centrifugal filtration of the second step ④ into a water precipitation crystallization kettle, adding 2000L of deionized water, heating to 90 ℃ under stirring, then cooling to 27 ℃ for water precipitation crystallization for 30-60 minutes to separate out the tetradecyl dicarboxylic acid product dissolved in the acetic acid solvent, filtering and separating by using a plate and frame filter press, wherein the filter cake obtained in the filter press is 79.5Kg of tetradecyl dicarboxylic acid crystal, and combining with the crystal obtained by the cooling crystallization of the second step, and then performing subsequent washing and drying steps together to obtain a tetradecyl dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Mixing the tetradecyl dicarboxylic acid crystals after centrifugal separation in the second step and the third step, leaching in a centrifuge by 200L of 98 wt% acetic acid, and centrifuging for 15 minutes after leaching; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Leaching a filter cake in a centrifuge by 2000L of deionized water, centrifuging and drying for 15 minutes, and washing the filter cake at room temperature; sending the water-phase leaching filtrate generated in the water-phase leaching process into a water-phase leaching filtrate storage tank for use in place of deionized water in the third step of a water separation crystallization process;
③ washing with water at room temperature, and centrifuging
Making 1200L of deionized water into slurry from ② filter cakes, sending the slurry into a water washing tank, adding 800L of deionized water into the water washing tank, stirring and washing for 30 minutes, performing centrifugal filtration, performing solid-liquid separation, and drying the filter cakes;
⑤ drying
And drying the filter cake from ③ items to obtain 635Kg of refined tetradecyl dicarboxylic acid, wherein the refined tetradecyl dicarboxylic acid reaches the following technical indexes:
the refining and purifying yield of the tetradecyl dicarboxylic acid is 96.20 percent.
Example 4. the present invention provides a method for refining and purifying tridecyl dicarboxylic acid with high yield and low cost, which comprises the following steps:
first step, dissolving and decolorizing
At room temperature, putting 800Kg of tridecyl dicarboxylic acid crude product with the tridecyl dicarboxylic acid content of 85 percent by mass, 2000L of 95 wt% industrial acetic acid and 6Kg of activated carbon into a decoloring reaction kettle, stirring, heating the materials in the decoloring kettle to 93 ℃, preserving the temperature for 15 minutes, filtering, performing solid-liquid separation, and sending the filtrate into a crystallization kettle for crystallization; and (3) washing a decolorant filter cake obtained after decoloring and filtering by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 85 ℃, feeding the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover tridecyl dicarboxylic acid carried in the decolorant activated carbon.
Second, cooling and crystallizing
And (3) putting the filtrate subjected to the first-step decolorization into a crystallization kettle, stirring, and performing gradient cooling crystallization.
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, cooling the decolorized filtrate from the first step to 80 ℃, and closing the cooling water.
② two-stage cooling and induced crystallization
And naturally cooling to 72 ℃ under stirring, adding tridecyl dicarboxylic acid with the purity of more than 99.8 percent as seed crystal, controlling the stirring speed to be 40r/min, rebounding the temperature in the crystallization kettle to 74 ℃, and then gradually reducing. The temperature naturally dropped to 68 ℃.
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, controlling the cooling speed from slow to fast, and finally cooling to 28 ℃ until the crystallization is complete.
The whole cooling crystallization time is controlled to be 6-8 hours.
④, centrifuging and filtering;
the completely crystallized material from item ③ above was centrifuged, the cake was rinsed, and the mother liquor was crystallized by water precipitation.
Third step, water precipitation crystallization
Putting the mother liquor generated by the centrifugal filtration of the second step ④ into a water separation crystallization kettle, adding 2000L of deionized water, stirring, heating to 88 ℃, then cooling to 28 ℃, performing water separation crystallization for 30-60 minutes to separate out the tridecyl dicarboxylic acid product dissolved in the acetic acid solvent, filtering and separating by using a plate-and-frame filter press, mixing the tridecyl dicarboxylic acid crystal 86.8Kg with the crystal obtained by the temperature reduction crystallization of the second step, and performing subsequent washing and drying steps together to obtain the tridecyl dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Combining the tridecyl dicarboxylic acid crystals after the centrifugal separation in the second step and the third step, leaching in a centrifuge by using 300L of 98 wt% acetic acid, and centrifuging for 15 minutes after leaching; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Leaching a filter cake in a centrifuge by 2000L of deionized water, centrifuging and drying for 15 minutes, and washing the filter cake at room temperature; sending the water-phase leaching filtrate generated in the water-phase leaching process into a water-phase leaching filtrate storage tank for use in place of deionized water in the third step of a water separation crystallization process;
③ washing with water at room temperature, and centrifuging
Making 1200L of deionized water into slurry from ② filter cakes, sending the slurry into a water washing tank, adding 800L of deionized water into the water washing tank, stirring and washing for 30 minutes, performing centrifugal filtration, performing solid-liquid separation, and drying the filter cakes;
⑤ drying
The filter cake from ③ is dried to obtain 654Kg of refined tridecyl dicarboxylic acid, which reaches the following technical indexes:
the refining and purifying yield of the tridecyl dicarboxylic acid is 96.18 percent.
Example 5. the refining and purifying method of undecyl dicarboxylic acid with high yield and low cost of the invention comprises the following steps:
first step, dissolving and decolorizing
At room temperature, 975Kg of undecyl dicarboxylic acid crude product with the weight percentage of 80% of undecyl dicarboxylic acid, 2000L of 95 wt% of industrial acetic acid and 6Kg of activated carbon are put into a decoloring reaction kettle, materials in the decoloring kettle are heated to 94 ℃ under stirring, the temperature is kept for 25 minutes, filtering and solid-liquid separation are carried out, and filtrate is sent into a crystallization kettle for crystallization; and (3) washing a decolorant filter cake obtained after decoloring and filtering by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 93 ℃, feeding the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover the undecyl dicarboxylic acid carried in the decolorant activated carbon.
Second, cooling and crystallizing
And (3) putting the filtrate subjected to the first-step decolorization into a crystallization kettle, stirring, and performing gradient cooling crystallization.
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, cooling the decolorized filtrate from the first step to 76 ℃, and closing the cooling water.
② two-stage cooling and induced crystallization
Naturally cooling to 74 ℃ under stirring, adding undecyl dicarboxylic acid with the purity of more than 99.8 percent as seed crystal, controlling the stirring speed to be 40r/min, rebounding the temperature in the crystallization kettle to 76 ℃, and then gradually reducing. The temperature naturally drops to 70 ℃.
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, controlling the cooling speed from slow to fast, and finally cooling to 25 ℃ until the crystallization is complete.
The whole cooling crystallization time is controlled to be 6-8 hours.
④, centrifuging and filtering;
the completely crystallized material from item ③ above was centrifuged, the cake was rinsed, and the mother liquor was crystallized by water precipitation.
Third step, water precipitation crystallization
Putting the mother liquor generated by the centrifugal filtration of the second step ④ into a water precipitation crystallization kettle, adding 2000L of deionized water, stirring, heating to 92 ℃, then cooling to 25 ℃, performing water precipitation crystallization for 30-60 minutes to separate out crystals of the undecyl dicarboxylic acid product dissolved in the acetic acid solvent, filtering and separating by using a plate and frame filter press, combining the filter cake obtained in the filter press with 106.2Kg of undecyl dicarboxylic acid crystals and the crystals obtained by the temperature reduction crystallization of the second step, and performing subsequent washing and drying steps together to obtain a main undecyl dicarboxylic acid product;
the fourth step, crystal washing
① acetic acid Leaching
Merging the undecyl dicarboxylic acid crystals after the centrifugal separation in the second step and the third step, leaching in a centrifugal machine by using 200L of 98 wt% acetic acid, and centrifuging for 15 minutes after leaching; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Leaching a filter cake in a centrifuge by 2000L of deionized water, centrifuging and drying for 15 minutes, and washing the filter cake at room temperature; sending the water-phase leaching filtrate generated in the water-phase leaching process into a water-phase leaching filtrate storage tank for use in place of deionized water in the third step of a water separation crystallization process;
③ washing with water at room temperature, and centrifuging
Making 1200L of deionized water into slurry from ② filter cakes, sending the slurry into a water washing tank, adding 800L of deionized water into the water washing tank, stirring and washing for 30 minutes, performing centrifugal filtration, performing solid-liquid separation, and drying the filter cakes;
⑤ drying
The filter cake from ③ is dried to obtain 751Kg of refined undecyl dicarboxylic acid, and the refined and purified undecyl dicarboxylic acid reaches the following technical indexes:
the refining and purifying yield of the undecyl dicarboxylic acid is 96.28 percent.
Claims (9)
1. A high-cost low long carbon chain dicarboxylic acid refining purification method of yield, regard long carbon chain dicarboxylic acid crude product that the fermentation process prepares as raw materials, use acetic acid as the solvent, refine and purify through recrystallization, through decolorizing and filtering, cooling crystallization, centrifugal separation, filter cake washing, oven dry the technological process and make long carbon chain dicarboxylic acid product, after the recrystallization mother liquor retrieves the solvent, the heavy component got, mix with long carbon chain dicarboxylic acid crude product, as refine and purify raw materials and recycle repeatedly, characterized by that:
①, the raw material long carbon chain dicarboxylic acid crude product for refining and purification directly enters the subsequent decolorization process without drying treatment;
②, washing the decolorant filter cake obtained after decoloration and filtration with a solvent acetic acid, and combining the obtained decolorant filter cake washing liquid and the decolorant filtration filtrate to enter a subsequent cooling crystallization process so as to recover long carbon chain dicarboxylic acid carried in the decolorant activated carbon;
③, before recovering the solvent, the recrystallization mother liquor firstly elutes and crystallizes, and then extracts the long carbon chain dicarboxylic acid product dissolved in the crystallization mother liquor again, wherein the elutriation crystallization is to add deionized water into the crystallization mother liquor to crystallize and separate out the long carbon chain dicarboxylic acid product dissolved in the acetic acid solvent, then the filtration and the separation are carried out, the obtained long carbon chain dicarboxylic acid crystal is combined with the crystal obtained by the first recrystallization, and the combined crystal and the crystal enter the subsequent leaching and drying processes to jointly prepare the long carbon chain dicarboxylic acid product;
④ recovering solvent from the filtered mother liquid after water separation and crystallization, recovering and utilizing by azeotropic distillation, separating water from acetic acid by azeotropic distillation process, using the separated water as water for water separation and crystallization in characteristic ③, and recycling the separated solvent acetic acid as solvent in the process of long carbon chain dicarboxylic acid refining and purification.
2. A process for the purification of long carbon chain dicarboxylic acids with high yield and low cost according to claim 1, wherein said long carbon chain dicarboxylic acid is C11～C18A straight chain saturated dicarboxylic acid.
3. The method according to claim 1, wherein ① said crude product of long carbon chain dicarboxylic acid is prepared from long carbon chain normal paraffin by microbial fermentation, filtering, decolorizing, acidifying, crystallizing, and filtering to obtain cake crystal with water content of 20 wt% or less, and can be directly used as refining material without drying.
4. The method according to claim 1, wherein the decolorizer cake obtained by the decolorizing and filtering of item ② is washed with acetic acid as a solvent, and the washing is carried out with industrial acetic acid containing acetic acid as a solvent in an amount of 95 wt% or more or recovered acetic acid.
5. The method for refining and purifying long-carbon-chain dicarboxylic acid with high yield and low cost according to claim 1, wherein a decolorizer filter cake obtained after the decolorization and filtration in item ② is washed with a solvent acetic acid, and the solvent acetic acid for washing is hot acetic acid with the temperature of 80-95 ℃.
6. The method for refining and purifying the long-carbon-chain dicarboxylic acid with high yield and low cost according to claim 1 is characterized in that ③ items of the water precipitation crystallization process include the steps of firstly adding deionized water into crystallization mother liquor under stirring, controlling the volume ratio of the mother liquor to the deionized water to be 1: 0.5-1, conducting water precipitation crystallization for 30-60 minutes under stirring to crystallize and separate out a long-carbon-chain dicarboxylic acid product dissolved in an acetic acid solvent, then conducting filtering separation by using a plate and frame filter press, combining the long-carbon-chain dicarboxylic acid crystal with the content of 65-80 wt% obtained in the filter press with the crystal obtained in the first recrystallization, and conducting subsequent leaching and drying steps to jointly obtain the long-carbon-chain dicarboxylic acid main product.
7. The method according to claim 1 or claim 6, wherein the deionized water added to the mother liquid during the water precipitation crystallization process in item ③ is the water phase leaching filtrate generated in the water phase leaching step in the long carbon chain dicarboxylic acid refining purification process.
8. The method according to claim 1, wherein the azeotropic distillation process is carried out by recovering the solvent from the filtered mother liquor after the water separation and crystallization in item ④:
the method comprises the steps of enabling filtered mother liquor after water separation crystallization treatment to enter an azeotropic distillation system, enabling an entrainer to be sec-butyl acetate preferably, collecting sec-butyl acetate-water azeotrope from the top of a distillation process tower at 85-95 ℃ in a gas phase mode, enabling the azeotrope to enter a phase splitter for layering after condensation, collecting a lower-layer water phase as water for water separation crystallization feeding in ① for recycling, enabling an upper-layer sec-butyl acetate phase to flow back to an azeotropic distillation kettle to participate in azeotropic distillation continuously, enabling the temperature of the upper-layer sec-butyl acetate phase to be controlled at 110-125 ℃ to collect acetic acid, collecting the acetic acid with the content being more than or equal to 95 wt% after cooling and heating, enabling the acetic acid to be used as an acetic acid solvent for recycling at a long-carbon-chain binary acid crude product dissolution and decoloration working section, and controlling the material temperature of the azeotropic distillation kettle.
9. The method for purifying a long carbon chain dicarboxylic acid with high yield and low cost according to claim 1, which comprises the following steps:
first step, dissolving and decolorizing
At room temperature, putting a crude long carbon chain dicarboxylic acid crude product with the water content of less than or equal to 20 wt%, acetic acid and activated carbon into a decoloring reaction kettle, heating the materials in the decoloring reaction kettle to 90-95 ℃ under stirring, preserving the temperature for 10-30 minutes, filtering, performing solid-liquid separation, and feeding the filtrate into a crystallization kettle for crystallization; washing a decolorant filter cake obtained after decoloration and filtration by using hot acetic acid with the content of more than or equal to 95 wt% and the temperature of 80-95 ℃, sending the obtained decolorant filter cake washing liquid into a crystallization kettle, and completing a subsequent cooling crystallization process together with the decolored filtrate so as to recover long carbon chain dicarboxylic acid carried in decolorant activated carbon;
second, cooling and crystallizing
Putting the filtrate decolored in the first step into a crystallization kettle, and carrying out gradient cooling crystallization under stirring:
① first stage cooling
In a crystallization kettle, stirring, starting an interlayer cooling water, and cooling the decolorized filtrate from step ① to 75-80 ℃;
② two-stage cooling and induced crystallization
Stirring, naturally cooling to 71-75 ℃, adding long carbon chain dibasic acid to induce seed crystal, and then continuously naturally cooling to 68-70 ℃;
③ three-stage cooling
Opening the interlayer cooling water, adjusting the flow rate of the cooling water, and cooling the temperature of the crystallization feed liquid to 20-30 ℃ until the crystallization is complete;
④, centrifuging and filtering;
centrifuging and filtering the completely crystallized material from item ③, washing the filter cake, and separating out the crystal from the mother liquor;
third step, water precipitation crystallization
Putting the mother liquor generated by centrifugal filtration in the second step ④ into a water precipitation crystallization kettle, adding deionized water under stirring, or adding water phase leaching filtrate generated in the water phase leaching process in the fourth step ②, wherein the addition amount of the water phase leaching filtrate is controlled to be 1: 0.5-1, heating to 85-95 ℃ under stirring, then cooling to 25-30 ℃, performing water precipitation crystallization for 30-60 minutes, crystallizing and separating out a long carbon chain dicarboxylic acid product dissolved in an acetic acid solvent, then performing filtration and separation by using a plate and frame filter press, mixing the long carbon chain dicarboxylic acid crystal with the filter cake content of 65-80 wt% obtained in the filter press with the crystal obtained by cooling and crystallization in the second step, and performing subsequent washing and drying steps together to obtain a long carbon chain dicarboxylic acid main product;
the fourth step, crystal washing
① acetic acid Leaching
Crystallizing the long carbon chain dicarboxylic acid after the centrifugal separation in the second step and the third step, leaching in a centrifugal machine by using a small amount of acetic acid, wherein the leaching amount of the acetic acid is 5-100% of that of the acetic acid for dissolution and decoloration in the first step; centrifugate produced in the leaching process is used as a solvent in the next batch feeding step of the production cycle; the filter cake after being dried is left in a centrifuge for preparing water phase for leaching;
② rinsing with water phase
Washing the filter cake in the centrifuge with deionized water or room temperature water washing filtrate generated in the subsequent ③ items, centrifuging and spin-drying again, and washing the filter cake with room temperature water;
③ washing with water at room temperature, and centrifuging
The filter cake from item ② is made into slurry by deionized water and then is sent into a water washing tank, the deionized water accounts for 70-120 percent of the mass of acetic acid used in the dissolving and decoloring step in the first step, the mixture is stirred and washed for 30 minutes in the water washing tank, centrifugal filtration is carried out, solid-liquid separation is carried out, the filter cake is ready for drying, the room-temperature water washing filtrate is sent into a room-temperature water washing filtrate storage tank and is ready for being used as water for water phase leaching in item ② in the fourth step of next batch production for recycling;
⑤ drying
And (3) drying the filter cake from the ③ item to obtain refined long carbon chain dicarboxylic acid, wherein the refined and purified long carbon chain dicarboxylic acid achieves the following technical indexes:
the refining and purifying yield of the long carbon chain dicarboxylic acid is more than or equal to 96.00 percent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414587.XA CN111099991A (en) | 2019-12-31 | 2019-12-31 | Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414587.XA CN111099991A (en) | 2019-12-31 | 2019-12-31 | Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111099991A true CN111099991A (en) | 2020-05-05 |
Family
ID=70425969
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911414587.XA Pending CN111099991A (en) | 2019-12-31 | 2019-12-31 | Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111099991A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112321418A (en) * | 2020-11-24 | 2021-02-05 | 淮安清江石油化工有限责任公司 | Refining method of long-chain dibasic acid |
| CN114438139A (en) * | 2020-10-31 | 2022-05-06 | 中国石油化工股份有限公司 | Method and device for preparing long-chain dicarboxylic acid |
| CN114507129A (en) * | 2020-10-28 | 2022-05-17 | 中国石油化工股份有限公司 | Refining method of organic acid in fermentation liquor |
| CN114685260A (en) * | 2020-12-29 | 2022-07-01 | 中国石油化工股份有限公司 | Method for purifying long-chain dicarboxylic acid |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103570525A (en) * | 2012-07-25 | 2014-02-12 | 中国石油化工股份有限公司 | Method for refining long-chain dibasic acid |
| CN104496793A (en) * | 2014-12-26 | 2015-04-08 | 淄博广通化工有限责任公司 | Method for refining long-carbon chain dicarboxylic acid |
| CN106588641A (en) * | 2016-12-20 | 2017-04-26 | 宁夏启元药业有限公司 | Method for reclaiming primary crystallized mother liquor of gulonic acid |
| CN108003015A (en) * | 2017-12-23 | 2018-05-08 | 淄博广通化工有限责任公司 | The process for refining and purifying of Long carbon chain dicarboxylic acids |
-
2019
- 2019-12-31 CN CN201911414587.XA patent/CN111099991A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103570525A (en) * | 2012-07-25 | 2014-02-12 | 中国石油化工股份有限公司 | Method for refining long-chain dibasic acid |
| CN104496793A (en) * | 2014-12-26 | 2015-04-08 | 淄博广通化工有限责任公司 | Method for refining long-carbon chain dicarboxylic acid |
| CN106588641A (en) * | 2016-12-20 | 2017-04-26 | 宁夏启元药业有限公司 | Method for reclaiming primary crystallized mother liquor of gulonic acid |
| CN108003015A (en) * | 2017-12-23 | 2018-05-08 | 淄博广通化工有限责任公司 | The process for refining and purifying of Long carbon chain dicarboxylic acids |
Non-Patent Citations (1)
| Title |
|---|
| 丁启圣主编: "《新型实用过滤技术 第4版》", 冶金工业出版社, pages: 69 - 70 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114507129A (en) * | 2020-10-28 | 2022-05-17 | 中国石油化工股份有限公司 | Refining method of organic acid in fermentation liquor |
| CN114438139A (en) * | 2020-10-31 | 2022-05-06 | 中国石油化工股份有限公司 | Method and device for preparing long-chain dicarboxylic acid |
| CN114438139B (en) * | 2020-10-31 | 2023-07-28 | 中国石油化工股份有限公司 | Method and device for preparing long-chain dibasic acid |
| CN112321418A (en) * | 2020-11-24 | 2021-02-05 | 淮安清江石油化工有限责任公司 | Refining method of long-chain dibasic acid |
| CN114685260A (en) * | 2020-12-29 | 2022-07-01 | 中国石油化工股份有限公司 | Method for purifying long-chain dicarboxylic acid |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111099991A (en) | Refining and purifying method for long carbon chain dicarboxylic acid with high yield and low cost | |
| CN104529741B (en) | The method of purification of Long carbon chain di-carboxylic acid | |
| CN111039777A (en) | Refining and purifying method of dodecyl dicarboxylic acid with high yield and low cost | |
| CN108003015A (en) | The process for refining and purifying of Long carbon chain dicarboxylic acids | |
| CN109535478B (en) | Method for recycling PA6 copolymerization modified PET polyester waste | |
| CN104496793A (en) | Method for refining long-carbon chain dicarboxylic acid | |
| CN111087298A (en) | Mixed long carbon chain dicarboxylic acid and preparation method thereof | |
| CN108101775A (en) | The process for refining and purifying of heneicosanedioic acid | |
| CN111099990B (en) | Recycling method of long carbon chain dicarboxylic acid refined crystallization mother liquor | |
| CN111171103B (en) | Method for extracting oryzanol by multiple solvents | |
| DE102014213637A1 (en) | Process and apparatus for concentration and crystallization of fermentable carboxylic acids | |
| CN111039776A (en) | High-purity mixed long carbon chain dicarboxylic acid and preparation method thereof | |
| CN109942411A (en) | Long-chain biatomic acid continuous crystallisation process | |
| CN105712887B (en) | A kind of production method of long-chain nylon salt | |
| CN108084015A (en) | The process for refining and purifying of dodecanedioic acid | |
| CN104844440B (en) | A kind of refining methd of long-chain mixed dibasic acid | |
| CN107250093B (en) | Method for producing succinic acid from fermentation broth using nanofiltration purification of recovered mother liquor | |
| CN108003014A (en) | The process for refining and purifying of tridecandioic acid | |
| CN111116352B (en) | Recycling method of dodecyl dicarboxylic acid refined crystallization mother liquor | |
| CN105712888B (en) | A kind of preparation method of long-chain nylon salt | |
| CN113773192B (en) | Method for purifying dodecyl dicarboxylic acid by mixed extractant | |
| CN108147962A (en) | The process for refining and purifying of tetracosandioic acid | |
| CN114805035B (en) | Method for purifying 4,4' -biphenol | |
| CN116199601B (en) | Refining and purifying process of high-content chlorothalonil | |
| CN111032623A (en) | Process for purifying long-chain amino acid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200505 |
|
| RJ01 | Rejection of invention patent application after publication |