CN103467237B - Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons - Google Patents
Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons Download PDFInfo
- Publication number
- CN103467237B CN103467237B CN201310419866.1A CN201310419866A CN103467237B CN 103467237 B CN103467237 B CN 103467237B CN 201310419866 A CN201310419866 A CN 201310419866A CN 103467237 B CN103467237 B CN 103467237B
- Authority
- CN
- China
- Prior art keywords
- gas
- aromatic hydrocarbons
- acid
- terephthalic acid
- benzene
- 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.)
- Active
Links
Abstract
The invention discloses a kind of method that terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons, comprise the following steps: after terephthalic acid residue drying, pulverizing, high-temperature gasification, under the effect of 450 DEG C ~ 550 DEG C and 0 ~ 2MPa, decarboxylation catalyst, carry out decarboxylic reaction, described high-temperature gasification temperature is at least 350 DEG C; The product obtained by decarboxylic reaction is cooled to 200 DEG C ~ 240 DEG C, through gas solid separation, is cooled to 20 DEG C ~ 80 DEG C further, then through gas-liquid separation, obtains gas and aromatic hydrocarbons mixed solution by being separated the gas obtained; The aromatic hydrocarbons mixed solution obtained, through rectification process, obtains benzene and the aromatic hydrocarbons mixed solution except benzene respectively.The present invention has taken into account environment protection and economic benefit, and the comprehensive utilization for PTA residue proposes a new direction, and the method can obtain the low boiling point arene such as benzene, toluene, high financial profit, energy-conserving and environment-protective.
Description
Technical field
The present invention relates to the process field of terephthalic acid residue, be specifically related to a kind of method that terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons.
Background technology
Purified terephthalic (purifiedterephthalicacid, PTA) is the important source material of textile industry and plastics industry, mainly for the production of trevira, coating, film etc.The fast development of terephthalic acid industry brings serious " three wastes " pollution problem, especially serious with the discharge of terephthalic acid residue.Containing a large amount of organic acids in terephthalic acid residue, except terephthalic acid, also have phenylformic acid, phthalic acid, m-phthalic acid, p-methylbenzoic acid, p-carboxybenzaldehyde and cobalt-manganese catalyst and other mechanical impuritys etc.Terephthalic acid residue is a difficult problem for environmental protection always, needs effective means badly and processes.
Recycling at present to chemical fibre industry terephthalic acid residue, domestic have many people to do research work.As the publication number Chinese patent literature that is CN1126730C discloses a kind of separating and purifying method of terephthaldehyde's acid waste products, by the sulfuric acid of 75% ~ 98% with 50% ~ 95% nitric acid after stirring, become nitration mixture for 1:1 ~ 9:1 joins in acid tank respectively by volume, then terephthaldehyde's acid waste products of solid is added in this nitration mixture; The slurry that above process generates is used filter screen filtration under negative pressure, and filter cake sends into washing pool after concentrating; Isolated for above process filter cake is washed with de-salted water in washing pool, generates terephthalic acid solid wet cake and deliver to moisture eliminator; Dry 20 ~ 40 minutes, obtain terephthalic acid solid finished product.
Publication number is the separation method that the Chinese patent literature of CN1012954B discloses a kind of terephthalic acid residue, according to the acid out principle of improvement Heng Geerfa, first washing process is carried out to oxidation residua, then under high temperature, salt of weak acid existence condition, selective reaction is carried out, terephthalic acid is separated with m-phthalic acid, carry out extracting with solvent again, mixed cell acid is separated with terephthalic acid, m-phthalic acid respectively.
Above-mentioned separation method is the difference utilizing aromatic acid physics and chemistry character, is separated one or more components wherein by unit operations such as extraction, fractionation and centrifugings.Because diprotic acid isomer is chemical and physical properties is extremely similar, cause separating technology complicated, cost is higher, generates a large amount of waste water in sepn process, and product purity is difficult to reach industrial requirements.
There are the problems referred to above in the Separation and Recovery based on PTA residue, someone puts forward the comprehensive utilization to PTA residue, active carbon method is prepared as the publication number Chinese patent literature that is CN1508067A discloses one oxidized dregs of terephthalic acid, by calcification, oxidation residua is made oxidation residua calcium salt, again oxidation residua calcium salt is carried out carbonization under isolated air or oxygen debt atmosphere, obtain a periporate shaped activated carbon 1, soluble metallic salt (mainly calcium carbonate) is removed again with pickling, drying, obtains final powdered carbon product.
And for example publication number is that the Chinese patent literature of CN1508167A discloses a kind of method utilizing the diprotic acid waste residues such as terephthalic acid to prepare unsaturated polyester resin, adopt containing the industrial residue containing diprotic acid such as terephthalic acid, phthalic acid, particularly terylene industrial produces the waste residue of terephthalic acid, replace or partly replace diprotic acid, particularly unsaturated polyester produced by Tetra hydro Phthalic anhydride, butene dioic acid.A kind of unsaturated dibasic acid and the catalyzer that reacts of dibasic alcohol ester of this invention development are tin protoxide, or tin salt or other stannous compound, and its addition is the significant quantity of catalyzer.
Summary of the invention
The invention provides a kind of method that terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons, the comprehensive utilization for PTA residue proposes a new direction, and the method can obtain the low boiling point arene such as benzene, toluene, high financial profit, energy-conserving and environment-protective.
Terephthalic acid residue catalytic decarboxylation prepares a method for aromatic hydrocarbons, comprises the following steps:
1), after terephthalic acid residue drying, pulverizing, high-temperature gasification, under the effect of 450 DEG C ~ 550 DEG C and 0 ~ 2MPa, decarboxylation catalyst, carry out decarboxylic reaction, described high-temperature gasification temperature is at least 350 DEG C;
2) product that decarboxylic reaction obtains is cooled to 200 DEG C ~ 240 DEG C, through gas solid separation, is cooled to 20 DEG C ~ 80 DEG C further by being separated the gas obtained, then through gas-liquid separation, obtains gas and aromatic hydrocarbons mixed solution;
3) step 2) the aromatic hydrocarbons mixed solution that obtains through rectification process, obtain benzene and the aromatic hydrocarbons mixed solution except benzene respectively.
Benzoic literization temperature (100 DEG C) is lower, has very big-difference with other binary aromatic acid, by distilling the phenylformic acid of rear refining recyclable higher degree.
As preferably, when content benzoic in described terephthalic acid residue is more than 5wt.%, terephthalic acid residue first through distillation, heating and gasifying, obtain thick phenylformic acid product again after condensation, and described heating and gasifying temperature is 260 DEG C ~ 270 DEG C; Remain non-residue after gasifying again by step 1) ~ 3) carry out.The distillation process of described terephthalic acid residue is carried out in batch fractionating tower.
As preferably, contain the inorganic salt of cobalt and manganese in step 1) in high-temperature gasification resistates, through acid dissolve, filtration, sodium bicarbonate precipitates, then obtains cobalt-manganese catalyst through being separated dried recovered.
As preferably, in step 1), decarboxylation catalyst comprises active ingredient and carrier, and active ingredient is ZnO, and carrier is Al
2o
3, ZnO and Al
2o
3mass ratio be 0.1 ~ 5.ZnO is the conductor oxidate of meta-alkalescence, and lattice energy is lower, and aromatic acid can generate carboxylate compound at ZnO chemical absorption of surface, and carboxylate salt decomposes generation aromatic hydrocarbons further.
Under above-mentioned decarboxylation catalyst effect, there is decarboxylic reaction under the high temperature conditions and generate the aromatic hydrocarbons such as benzene, toluene, biphenyl and phenylformic acid in terephthalic acid residue.
As preferably, in step 1), the reactant mass space velocity of decarboxylic reaction is 0.1/h ~ 2/h, more preferably 0.1/h ~ 0.6/h.Appropriate rare gas element to be passed in decarboxylic reaction, regulate the duration of contact of terephthalic acid residue and decarboxylation catalyst, prevent the formation causing carbon deposit because of overstand.Under the identical residence time, weight hourly space velocity is higher, and aromatic acid rate is lower.When mass space velocity is 2/h, PTA residue still can keep the transformation efficiency of more than 60%.
In the reaction product that the decarboxylic reaction of step 1) is obtained, mainly comprise benzene, toluene, carbonic acid gas, phenylformic acid and biphenyl etc., in process of cooling, phenylformic acid and unreacted benzene diprotic acid are first separated from gas; Carbonic acid gas and aromatic hydrocarbons gas-liquid separator, through being cooled to 20 DEG C ~ 80 DEG C further, separate by residual gas component.
Step 2) in the solid that goes out through gas solid separation again after distillation, heating and gasifying, condensation, obtain thick phenylformic acid product, described heating and gasifying temperature is 260 DEG C ~ 270 DEG C; Remain non-residue after gasifying again by step 1) ~ 3) carry out, further increase the utilization ratio of terephthalic acid residue.
In step 1), terephthalic acid residue carries out high-temperature gasification through high temperature gasifier, carries out decarboxylic reaction through decarboxylic reaction device; Step 2) in cool through Heat Exchanger in Circulating Water System, carry out gas solid separation through gas-solid separator.As preferably, the gasifier related in the technique of terephthalic acid residue catalytic decarboxylation aromatic hydrocarbons, batch fractionating tower, decarboxylic reaction device, interchanger, gas-solid separator all arrange stand-by unit, be convenient to the solid residue in each device of periodic cleaning, solid matter is avoided to block process unit or pipeline, so that decarboxylation technique can normally be run continuously.
As preferably, in step 3), the rectifying of aromatic hydrocarbons mixed solution is carried out in rectifying tower, and separation condition is: bottom temperature 100 DEG C ~ 150 DEG C, tower top temperature 80 DEG C ~ 90 DEG C.After being separated, purer benzene can being obtained from tower top, obtain other aromatic hydrocarbons mixed solution from tower reactor.
As preferably, step 2) in the product that obtains of decarboxylic reaction cool through interchanger, after interchanger heat-eliminating medium is completed heat exchange, the rectifying tower reactor heating medium again as aromatic hydrocarbon uses, can reduce energy consumption, raising efficiency of energy utilization.
The invention provides a kind of method that terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons, by the method, terephthalic acid residue decarboxylation can be obtained aromatic product and recovery of benzoic acid.Compared with prior art, tool of the present invention has the following advantages:
The present invention is that the comprehensive utilization of terephthalic acid residue proposes a new direction, achieve the high value added utilization of terephthalic acid residue, relative to the recoverying and utilizing method of other terephthalic acid residues, the present invention does not need to use a large amount of solvent and acid-alkali washing, a large amount of waste liquids can not be produced, safety and environmental protection; Adopt heterogeneous decarboxylic reaction, catalyzer and product are easily separated, and greatly simplifie last handling process, decrease energy consumption and fund input.
The present invention is a kind of method that brand-new terephthalic acid residue is recycled, and by rational Process configuration, can obtain aromatic product and recovery of benzoic acid, have good economic benefit and wide application prospect.
The selectivity of the present invention to raw material is low, is applicable to component prepared by different production technique and the different terephthalic acid residue of content, all can obtains the low boiling point arenes such as benzene, toluene and biphenyl through method of the present invention.Advantages such as having taken into account environment protection and economic benefit, had that reaction yield is high, side reaction is few, pollution that constant product quality, reaction produce is few.
Accompanying drawing explanation
Fig. 1 is the method flow schematic diagram that embodiment 1 terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons;
Fig. 2 is the method flow schematic diagram that embodiment 3 terephthalic acid residue catalytic decarboxylation prepares aromatic hydrocarbons.
Embodiment
Embodiment 1
| Component | Oxidation residua |
| Terephthalic acid | 30.3% |
| M-phthalic acid | 35.4% |
| Phthalic acid | 0.66% |
| Phenylformic acid | 30.5% |
| P-methylbenzoic acid | 1.07% |
| P-tolyl aldehyde | 0.32% |
| Alkali insolubles | 1.01% |
| Ash content | 0.74% |
1) oxidized dregs of terephthalic acid of drying being heated to about 260 DEG C makes phenylformic acid gasify, and each component concentration of PTA oxidation residua as shown above, obtains thick phenylformic acid product after the product condensation after gasification.Reclaiming in PTA residue and obtaining phenylformic acid is 26.47wt.%;
2) the non-gasification substance that obtains of step 1) or unclassified stores drying and crushing, be delivered to high temperature gasifier through feeding-in solid body machine and gasify more than 350 DEG C.Resistates in gasifier is mainly containing inorganic salt and ash contents such as cobalt manganese, and with acid dissolve, filter, sodium bicarbonate precipitates, and is then separated dried recovered cobalt-manganese catalyst;
3) by step 2) vapour that obtains passes into filling decarboxylation catalyst (30wt.%ZnO, 5wt.%Cr
2o
3, 65wt.%Al
2o
3) reactor, reactor feed gas is 0.5/h at mass space velocity, carries out decarboxylic reaction under 500 DEG C and normal pressure.
4) the reacted product of step 3) is cooled to 200 DEG C, realizes gas and be separated with solid after gas-solid separator.PTA residue transforms substantially completely, only has a small amount of solid phenylformic acid to isolate.
5) gas that step 4) obtains is cooled to 30 DEG C further, by gas-liquid separator, realizes being separated of gas and aromatic hydrocarbons.
Except benzene, only contain a small amount of toluene and biphenyl etc. in aromatic hydrocarbons, can not carry out refining and directly sell as product.In liquid product, the purity of benzene reaches more than 95%, and the yield of benzene is close to 70%.
Embodiment 2
Adopt the oxidized dregs of terephthalic acid with embodiment 1 same composition and content, decarboxylation reaction conditions is: temperature 550 DEG C, pressure are 2MPa, and other processing condition are constant.
Reclaim in PTA residue and obtain phenylformic acid 26.47wt.%, the product after decarboxylic reaction is cooled to 200 DEG C, realizes gas and be separated with solid after gas-solid separator.Remaining PTA residue has 89% conversion, isolates the solid mixture of phenylformic acid and benzene diprotic acid, and wherein phenylformic acid is about containing 16%.Again the phenylformic acid in solid mixture is reclaimed.
Except benzene, only contain a small amount of toluene and biphenyl etc. in aromatic hydrocarbons, the purity of benzene reaches more than 95%, and the yield of benzene is close to 57%.
Embodiment 3
| Component | Rinsing residue |
| Terephthalic acid | 76.6% |
| M-phthalic acid | 0.01% |
| Phthalic acid | 0.01% |
| Phenylformic acid | 0.85% |
| P-methylbenzoic acid | 20.52% |
| P-tolyl aldehyde | 0.46% |
| Alkali insolubles | 0.75% |
| Ash content | 0.80% |
1) by the terephthalic acid rinsing residue drying and crushing of drying, each component concentration of PTA oxidation residua as shown above, is delivered to high temperature gasifier through feeding-in solid body machine and gasifies more than 350 DEG C.Resistates in gasifier is mainly containing inorganic salt and ash contents such as cobalt manganese, and with acid dissolve, filter, sodium bicarbonate precipitates, and is then separated dried recovered cobalt-manganese catalyst;
2) vapour that step 1) obtains is passed into filling decarboxylation catalyst (30wt.%ZnO, 5wt.%Cr
2o
3, 65wt.%Al
2o
3) reactor, reactor feed gas mass space velocity be 0.6/h, carry out decarboxylic reaction under 500 DEG C and normal pressure.
3) step 2) reacted product is cooled to 240 DEG C, and after gas-solid separator, realize gas be separated with solid.PTA residue transformation efficiency is 95.3%, and the phenylformic acid containing 32wt.% in solid, is back to the process of step 1);
4) gas that step 3) obtains is cooled to 60 DEG C further, by gas-liquid separator, realizes being separated of gas and aromatic hydrocarbons.Aromatic hydrocarbons is separated further by rectifying tower, and tower top can obtain purer benzene, and tower reactor can obtain toluene slightly.Wherein the yield of benzene is 63.4%, and the yield of crude cresylic acid is 83.4%.
Claims (1)
1. terephthalic acid residue catalytic decarboxylation prepares a method for aromatic hydrocarbons, it is characterized in that, comprises the following steps:
1) oxidized dregs of terephthalic acid of drying being heated to 260 DEG C makes phenylformic acid gasify, and obtains thick phenylformic acid product after the product condensation after gasification; Reclaiming in purified terephthalic residue and obtaining phenylformic acid is 26.47wt.%;
Each component concentration of described purified terephthalic oxidation residua is as follows:
2) step 1) the non-gasification substance that obtains or unclassified stores drying and crushing, be delivered to high temperature gasifier through feeding-in solid body machine and gasify more than 350 DEG C; Resistates in gasifier is mainly containing cobalt manganese inorganic salt and ash content, and with acid dissolve, filter, sodium bicarbonate precipitates, and is then separated dried recovered cobalt-manganese catalyst;
3) by step 2) vapour that obtains passes into the reactor of filling decarboxylation catalyst, and reactor feed gas is 0.5/h at mass space velocity, carries out decarboxylic reaction under 500 DEG C and normal pressure;
Described decarboxylation catalyst consist of 30wt.%ZnO, 5wt.%Cr
2o
3, 65wt.%Al
2o
3;
4) step 3) reacted product is cooled to 200 DEG C, and after gas-solid separator, realize gas be separated with solid; Purified terephthalic residue transforms substantially completely, only has a small amount of solid phenylformic acid to isolate;
5) step 4) gas that obtains is cooled to 30 DEG C further, by gas-liquid separator, realizes being separated of gas and aromatic hydrocarbons;
Except benzene, only contain a small amount of toluene and biphenyl in aromatic hydrocarbons, can not carry out refining directly as product sale, in liquid product, the purity of benzene reaches more than 95%, the yield 70% of benzene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310419866.1A CN103467237B (en) | 2013-09-13 | 2013-09-13 | Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310419866.1A CN103467237B (en) | 2013-09-13 | 2013-09-13 | Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103467237A CN103467237A (en) | 2013-12-25 |
| CN103467237B true CN103467237B (en) | 2016-03-30 |
Family
ID=49792320
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310419866.1A Active CN103467237B (en) | 2013-09-13 | 2013-09-13 | Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103467237B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109694319A (en) * | 2017-10-23 | 2019-04-30 | 杭州双安科技有限公司 | A kind of device and method for handling the solid waste containing organic acid |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB735300A (en) * | 1952-04-16 | 1955-08-17 | Ici Ltd | Improvements in and relating to the production of aromatic hydrocarbons and derivatives thereof |
| US4266084A (en) * | 1979-10-19 | 1981-05-05 | Standard Oil Company (Indiana) | Non-catalytic pyrolysis of residues from aromatic carboxylic acid manufacture |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6143130A (en) * | 1984-08-07 | 1986-03-01 | Nippon Shokubai Kagaku Kogyo Co Ltd | Production of 1,2,3,4-tetrafluorobenzene |
| DD276683A1 (en) * | 1988-11-02 | 1990-03-07 | Petrolchemisches Kombinat | METHOD FOR PRODUCING A BENZOESAEURE PHTHALSAFE ANHYDRIDE MIXTURE FROM THE RESOURCE OF TEREPHTHALIC ACID MANUFACTURE |
| US5003103A (en) * | 1989-11-20 | 1991-03-26 | Occidental Chemical Corporation | Preparation of 2-choloro-4,5-difluorobenzoic acid from 4,5-difluorophthalic anhydride of 4,5-difluorophthalic acid |
| JPH08243394A (en) * | 1995-03-09 | 1996-09-24 | Arakawa Chem Ind Co Ltd | Catalyst for selectively reducing ester position of aromatic carboxylic ester, and production of the same and aromatic alcohol compound |
| KR101930087B1 (en) * | 2011-07-26 | 2018-12-18 | 에스케이이노베이션 주식회사 | A method for producing aromatic hydrocarbon from byproducts of aromatic carboxylic acids and/or their alkyl esters preparation processes |
-
2013
- 2013-09-13 CN CN201310419866.1A patent/CN103467237B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB735300A (en) * | 1952-04-16 | 1955-08-17 | Ici Ltd | Improvements in and relating to the production of aromatic hydrocarbons and derivatives thereof |
| US4266084A (en) * | 1979-10-19 | 1981-05-05 | Standard Oil Company (Indiana) | Non-catalytic pyrolysis of residues from aromatic carboxylic acid manufacture |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103467237A (en) | 2013-12-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3170290B2 (en) | Method for producing light oil from waste plastic containing phthalic polyester and / or polyvinyl chloride | |
| CN100393677C (en) | Process for extracting 1-methylnaphthalene and 2-methylnaphthalene from tar | |
| CN101255107A (en) | Resourceful treatment method of purified terephthalic acid waste residue | |
| CN101362692A (en) | Technology method for producing isopropyl trifluoroacetate and apparatus | |
| CN101898952A (en) | Method and device for treating low-concentration acetic acid wastewater | |
| CN108017109B (en) | Method for recycling BDO waste liquid | |
| CN103467237B (en) | Terephthalic acid residue catalytic decarboxylation prepares the method for aromatic hydrocarbons | |
| CN114436806A (en) | Method for preparing disodium terephthalate and high-purity hydrogen by one-step low-temperature conversion of PET polyester waste plastic | |
| CN102381776B (en) | Catalytic hydrogenation desorption method for oxygenated compound in Fischer-Tropsch synthesized water phase and application thereof | |
| KR20090028173A (en) | Method for emulsifying waste matter | |
| JP2002212571A (en) | Method for thermal cracking of waste plastic | |
| JP2007145885A (en) | Dye-extraction depolymerization method of dyed polyester fiber | |
| CN106316753A (en) | Separation and purification technology of 2-methylnaphthalene | |
| CN105111074B (en) | A kind of alkali decrement waste water solid residue esterification recoverying and utilizing method | |
| KR101552868B1 (en) | Method for chemical recycling of pet wastes | |
| CN102775538A (en) | Production method of polyvinyl alcohol | |
| CN105561620A (en) | Water-containing high-boiling point solvent recovery process and apparatus thereof | |
| Sato et al. | Chemical recycling process of poly (ethylene terephthalate) in high-temperature liquid water | |
| US3149920A (en) | Production of sulfur | |
| CN104030912A (en) | Environment-friendly method for preparing binary acid by recycling cyclohexane oxidation byproducts | |
| JPS6019756B2 (en) | Method for recovering maleic anhydride from distillation residue | |
| TWI783048B (en) | Catalyst regeneration method, and carbonate production method | |
| CN104629083B (en) | A kind of processing method that regeneration is carried out to multiple cloth waste plastics | |
| CN104072371A (en) | Preparation method of dimethyl phthalate (DMP) | |
| CN108624354A (en) | A kind of method of organic by-products in Treatment of Cyclohexanone production process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |