CN102993061B - Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid - Google Patents
Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid Download PDFInfo
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- CN102993061B CN102993061B CN 201210264861 CN201210264861A CN102993061B CN 102993061 B CN102993061 B CN 102993061B CN 201210264861 CN201210264861 CN 201210264861 CN 201210264861 A CN201210264861 A CN 201210264861A CN 102993061 B CN102993061 B CN 102993061B
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- naphthalene
- disulfonic acid
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- mother liquor
- naphthalene disulfonic
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- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 239000007788 liquid Substances 0.000 title abstract description 10
- 238000004519 manufacturing process Methods 0.000 title abstract description 5
- 230000001131 transforming effect Effects 0.000 title abstract 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims abstract description 19
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 claims abstract description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 15
- 230000007062 hydrolysis Effects 0.000 claims abstract description 14
- 238000006460 hydrolysis reaction Methods 0.000 claims abstract description 14
- VILFVXYKHXVYAB-UHFFFAOYSA-N naphthalene-2,7-disulfonic acid Chemical compound C1=CC(S(O)(=O)=O)=CC2=CC(S(=O)(=O)O)=CC=C21 VILFVXYKHXVYAB-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000006243 chemical reaction Methods 0.000 claims abstract description 9
- 238000003756 stirring Methods 0.000 claims abstract description 8
- 238000012546 transfer Methods 0.000 claims abstract description 7
- 239000012452 mother liquor Substances 0.000 claims description 20
- VILFVXYKHXVYAB-UHFFFAOYSA-L naphthalene-2,7-disulfonate(2-) Chemical compound C1=CC(S([O-])(=O)=O)=CC2=CC(S(=O)(=O)[O-])=CC=C21 VILFVXYKHXVYAB-UHFFFAOYSA-L 0.000 claims description 18
- YZBGUDOBFPDWKS-UHFFFAOYSA-N 2-[4-(trifluoromethoxy)anilino]benzoic acid Chemical compound OC(=O)C1=CC=CC=C1NC1=CC=C(OC(F)(F)F)C=C1 YZBGUDOBFPDWKS-UHFFFAOYSA-N 0.000 claims description 10
- 238000009413 insulation Methods 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 4
- 230000006837 decompression Effects 0.000 claims description 4
- 239000002699 waste material Substances 0.000 abstract description 2
- 238000001816 cooling Methods 0.000 abstract 3
- 239000012295 chemical reaction liquid Substances 0.000 abstract 2
- 238000010438 heat treatment Methods 0.000 abstract 2
- 238000005086 pumping Methods 0.000 abstract 2
- 239000002912 waste gas Substances 0.000 abstract 1
- 239000002351 wastewater Substances 0.000 abstract 1
- 239000000047 product Substances 0.000 description 15
- 230000008901 benefit Effects 0.000 description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 5
- DPDMMXDBJGCCQC-UHFFFAOYSA-N [Na].[Cl] Chemical compound [Na].[Cl] DPDMMXDBJGCCQC-UHFFFAOYSA-N 0.000 description 5
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 5
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 5
- FITZJYAVATZPMJ-UHFFFAOYSA-L naphthalene-2,6-disulfonate(2-) Chemical compound C1=C(S([O-])(=O)=O)C=CC2=CC(S(=O)(=O)[O-])=CC=C21 FITZJYAVATZPMJ-UHFFFAOYSA-L 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 3
- 238000003912 environmental pollution Methods 0.000 description 3
- 239000000706 filtrate Substances 0.000 description 3
- 229910052938 sodium sulfate Inorganic materials 0.000 description 3
- 235000011152 sodium sulphate Nutrition 0.000 description 3
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 description 2
- WBZKQQHYRPRKNJ-UHFFFAOYSA-L disulfite Chemical compound [O-]S(=O)S([O-])(=O)=O WBZKQQHYRPRKNJ-UHFFFAOYSA-L 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000008247 solid mixture Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- FZUJWWOKDIGOKH-UHFFFAOYSA-N sulfuric acid hydrochloride Chemical compound Cl.OS(O)(=O)=O FZUJWWOKDIGOKH-UHFFFAOYSA-N 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a preparation method of a 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid. The method is characterized by comprising the following steps of: (I) pumping 1,6-naphthalenedisulfonic mother liquid containing 30-70% of water into a reaction kettle, and performing reduced-pressure concentration, wherein the vacuum degree is -0.08 to -0.095 Mpa, and the temperature does not exceed 180 DEG C; (II) when the water content is 14-15%, stopping heating; (III) adding naphthalene and sulfuric acid, heating to 180-190 DEG C, and preserving heat for 5 hours; (IV) after cooling to 110-120 DEG C, and transferring the reaction liquid into a transfer kettle, and after cooling down to 120 DEG C, pumping the reaction liquid into a hydrolysis kettle with water, wherein the hydrolysis temperature does not exceed 130 DEG C; (V) stirring for half an hour, cooling to 10-20 DEG C, and centrifuging to obtain 2,7-naphthalene disulfonic acid; and (VI) salifying to obtain 2,7-sodium naphthalenedisulfonate. The method disclosed by the invention has low cost, requires small investment and discharges little three wastes (wastegas, waste water and individual residue).
Description
Technical field
The invention belongs to chemical field, particularly a kind of 1,6-naphthalene disulfonic acid product mother liquid that utilizes transforms the preparation method who produces 2,7-naphthalene disulfonate product.
Background technology
The technology of producing 2,7-naphthalene disulfonate at present is as follows:
1, with 1,6-naphthalene disulfonic acid mother liquor concentrating under reduced pressure;
2, in concentrated solution, add sulfuric acid, refined naphthalene, catalyst reaction;
3, reacting liquid temperature is dropped to below 100 ℃, add sodium-chlor and sodium sulfate and stir, keep the system negative pressure, remove hydrogenchloride wherein;
4, liquid-solid mixture insulation is filtered, obtain thick 2,6-naphthalene disulfonate solid and filtrate I;
What 5, will obtain is thick 2, and 6-naphthalene disulfonate solid obtains smart 2,6-naphthalene disulfonate solid and filtrate II with metabisulfite solution insulation washing;
6, add water after filtrate I, II are merged, the sodium-chlor crystallization obtains 2,7-naphthalene disulfonate product.
Find that following some weak point is arranged after the test by line correlation that existing technology research is gone forward side by side:
One, in its technology the 3rd goes on foot, because temperature is near 100 ℃, in adding sodium-chlor and sodium sulfate salification process, can produce a large amount of hydrogenchloride, the effect of negative-pressure operation is that a large amount of hydrogen chloride gas enter air, causes serious topsoil, and another part hydrogenchloride also can cause heavy corrosion to equipment.
Its two, obtain 2, the 6-naphthalene disulfonate owing to reasons such as markets, existing is not developed derived product, is not have industrial utilization to be worth substantially, just as " solid giving up ".
Its three, its technology in the 5th step with metabisulfite solution insulation washing 2,6-naphthalene disulfonate, will certainly increase the mother liquor discharge capacity.
They are four years old, can find out from its technological process, contain a large amount of sodium sulfate, sodium-chlor, 2 in the mother liquor of decontaminated water treatment plant, 7-naphthalene disulfonate, 2, other impurity such as 6-naphthalene disulfonate and sulfuric acid hydrochloric acid, and the mother liquor amount is bigger, difficult treatment, cost is higher, and both unfavorable environmental protection cause very large economy pressure to enterprise again.
Summary of the invention
At above-mentioned the deficiencies in the prior art, the purpose of this invention is to provide a kind of 1,6-naphthalene disulfonic acid product mother liquid that utilizes and transform the preparation method who produces 2,7-naphthalene disulfonate product, little, the energy-conserving and environment-protective of this method environmental pollution.
Technical scheme of the present invention is: a kind of 1,6-naphthalene disulfonic acid mother liquor that utilizes transforms the preparation method who produces 2,7-naphthalene disulfonate product, and it is characterized in that: this method comprises the steps:
Step 1: will contain 1 of 30%-70% moisture, 6-naphthalene disulfonic acid mother liquor suction reactor, concentrating under reduced pressure, vacuum tightness is-0.08--0.095Mpa that temperature is no more than 180 ℃;
Step 2: when moisture during at 14-15%, stop to heat;
Step 3: add naphthalene and sulfuric acid, be heated to 180-190 ℃ after insulation 5 hours;
Step 4: change reaction solution over to the transfer still when being cooled to 110-120 ℃, be cooled to be extracted into after 120 ℃ in the hydrolysis kettle that water is housed, hydrolysis temperature must not be above 130 ℃;
Step 5: stir half an hour, be cooled to 10-20 ℃ after, centrifugal 2,7-naphthalene disulfonic acid;
Step 6: salify gets 2,7-naphthalene disulfonate.
Advantageous effect of the present invention is: this method has taken full advantage of above-mentioned 1, sulfuric acid in the 6-naphthalene disulfonic acid mother liquor and a large amount of naphthene sulfonic acid, prepare 2 by intramolecular rearrangement, the 7-naphthalene disulfonate, with present production 2, the technology of 7-naphthalene disulfonate is compared, low, the less investment of this method production cost, three waste discharge is few, has reduced environmental pollution, has improved economic benefit.
Embodiment
Below in conjunction with specific embodiment the present invention is further described:
Embodiment one
A kind of 1,6-naphthalene disulfonic acid product mother liquid that utilizes transforms the novel method of producing 2,7-naphthalene disulfonate product, comprises the steps:
1, with 2600kg1,6-naphthalene disulfonic acid mother liquor suction reactor, water is steamed in decompression, and vacuum tightness is-0.08Mpa.
2, when being warmed up to 170 ℃, detecting moisture is 14.3%, stops to steam water.
3, add 440kg naphthalene and 770kg sulfuric acid, insulation is 5 hours when being heated to 180 ℃.
4, reaction solution is changed over to the transfer still, be cooled to be extracted into after 110 ℃ in the hydrolysis kettle that 1000kg water is housed, hydrolysis temperature must not be above 130 ℃.
5, hydrolyzed solution is cooled to 10 ℃ of centrifugal 2,7-naphthalene disulfonic acids that get after stirring half an hour, and output is 800kg, and purity is 93%.
6, salify gets 2,7-naphthalene disulfonate 480Kg, and purity is 98.5%.
Example example two
A kind of 1,6-naphthalene disulfonic acid product mother liquid that utilizes transforms the novel method of producing 2,7-naphthalene disulfonate product, comprises the steps:
1, with 2600kg1,6-naphthalene disulfonic acid mother liquor suction reactor, water is steamed in decompression, and vacuum tightness is-0.095Mpa.
2, when being warmed up to 180 ℃, detecting moisture is 14.8%, stops to steam water.
3, add 440kg naphthalene and 770kg sulfuric acid, be heated to 183 ℃ after insulation 5 hours.
4, reaction solution is changed over to the transfer still, be cooled to be extracted into after 110 ℃ in the hydrolysis kettle that 1000kg water is housed, hydrolysis temperature must not be above 130 ℃.
5, hydrolyzed solution is cooled to 15 ℃ of centrifugal 2,7-naphthalene disulfonic acids that get after stirring half an hour, and output is 830kg, and purity is 93.1%.
6, salify gets 2,7-naphthalene disulfonate 500Kg, and purity is 98.6%.
Embodiment recited above is described preferred implementation of the present invention; be not that the spirit and scope of the present invention are limited; under the prerequisite that does not break away from design concept of the present invention; common engineering technical personnel make technical scheme of the present invention in this area various modification and improvement; all should fall into protection scope of the present invention; the technology contents that the present invention asks for protection all is documented in claims.
The present invention is to 1, the comprehensive utilization of 6-naphthalene disulfonic acid product mother liquid, taken full advantage of 1, a large amount of sulfuric acid and sulfonated bodies in the 6-naphthalene disulfonic acid mother liquor, when reducing production costs, digest the mother liquor that produces in 1, the 6-naphthalene disulfonic acid process of producing product in a large number, not only have favorable economic benefit, aspect energy-conserving and environment-protective, also received the good social benefit simultaneously.
Compare with existing technology, the present invention has following advantage:
1, the HCI of Chan Shenging is few.Should reduce more than 70%, reason is as follows: the one, and the salify temperature is low, between 70-80 ℃, and existing technology salify in the time of 100 ℃; The 2nd, this method is carried out salify after 2,7-naphthalene disulfonic acid separates, and sodium-chlor is not only with 2 when salify and have technology, and single sulfonic acid reaction, sulfuric acid wherein that 6-naphthalene disulfonic acid, 2,7-naphthalene disulfonic acid reach wherein also can act on a large amount of hydrogenchloride of generation.
2, this method does not produce 2,6-naphthalene disulfonate.This method directly obtains 2,7-naphthalene disulfonic acid and then salify by separating, and can not produce 2,6-naphthalene disulfonate, and that existing technology can produce in salification process is a large amount of 2, and the 6-naphthalene disulfonate owing to there is not industrial utilization to be worth, just as solid useless, causes environmental pollution.
3, mother liquor is few.This method obtain 2, the 6-naphthalene disulfonic acid can further transform and obtain 2,7-naphthalene disulfonate (existing public technology).Mother liquor behind the salify can be applied mechanically repeatedly and carry out salify simultaneously, has significantly reduced the mother liquor quantity discharged.
Claims (3)
1. one kind is utilized 1,6-naphthalene disulfonic acid mother liquor to transform the preparation method who produces 2,7-naphthalene disulfonate product, and it is characterized in that: this method comprises the steps:
Step 1: will contain 1 of 30%-70% moisture, 6-naphthalene disulfonic acid mother liquor suction reactor, concentrating under reduced pressure, vacuum tightness is-0.08--0.095Mpa that temperature is no more than 180 ℃;
Step 2: when moisture during at 14-15%, stop to heat;
Step 3: add naphthalene and sulfuric acid, be heated to 180-190 ℃ after insulation 5 hours;
Step 4: change reaction solution over to the transfer still when being cooled to 110-120 ℃, be cooled to be extracted into after 120 ℃ in the hydrolysis kettle that water is housed, hydrolysis temperature must not be above 130 ℃;
Step 5: stir half an hour, be cooled to 10-20 ℃ after, centrifugal 2,7-naphthalene disulfonic acid;
Step 6: salify gets 2,7-naphthalene disulfonate.
2. a kind of 1,6-naphthalene disulfonic acid mother liquor that utilizes according to claim 1 transforms the preparation method who produces 2,7-naphthalene disulfonate product, and it is characterized in that: this method comprises the steps:
Step 1: with 2600kg1,6-naphthalene disulfonic acid mother liquor suction reactor, decompression is heated, and vacuum tightness is-0.08Mpa.
Step 2: when being warmed up to 170 ℃, detecting moisture is 14.3%, stops to heat;
Step 3: add 440kg naphthalene and 770kg sulfuric acid, insulation is 5 hours when being heated to 180 ℃;
Step 4: change reaction solution over to the transfer still, be cooled to be extracted into after 110 ℃ in the hydrolysis kettle that 1000kg water is housed, hydrolysis temperature must not be above 130 ℃;
Step 5: hydrolyzed solution is cooled to 10 ℃ of centrifugal 2,7-naphthalene disulfonic acids that get after stirring half an hour, and output is 800kg, and purity is 93%;
Step 6: salify gets 2,7-naphthalene disulfonate 480Kg, and purity is 98.5%.
3. a kind of 1,6-naphthalene disulfonic acid mother liquor that utilizes according to claim 1 transforms the preparation method who produces 2,7-naphthalene disulfonate product, and it is characterized in that: this method comprises the steps:
Step 1: with 2600kg1,6-naphthalene disulfonic acid mother liquor suction reactor, decompression is heated, and vacuum tightness is-0.095Mpa;
Step 2: when being warmed up to 180 ℃, detecting moisture is 14.8%, stops to heat;
Step 3: add 440kg naphthalene and 770kg sulfuric acid, be heated to 183 ℃ after insulation 5 hours;
Step 4: change reaction solution over to the transfer still, be cooled to be extracted into after 110 ℃ in the hydrolysis kettle that 1000kg water is housed, hydrolysis temperature must not be above 130 ℃;
Step 5: hydrolyzed solution is cooled to 15 ℃ of centrifugal 2,7-naphthalene disulfonic acids that get after stirring half an hour, and output is 830kg, and purity is 93.1%;
Step 6: salify gets 2,7-naphthalene disulfonate 500Kg, and purity is 98.6%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210264861 CN102993061B (en) | 2012-07-30 | 2012-07-30 | Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201210264861 CN102993061B (en) | 2012-07-30 | 2012-07-30 | Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid |
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| Publication Number | Publication Date |
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| CN102993061A CN102993061A (en) | 2013-03-27 |
| CN102993061B true CN102993061B (en) | 2013-09-18 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105777589A (en) * | 2016-03-31 | 2016-07-20 | 常州大学 | Synthesis method of 4-isopropyl-2,5-sodium dimethylbenzenesulfonate |
| CN106748899B (en) * | 2016-12-23 | 2018-11-02 | 平顶山奥思达科技有限公司 | Naphthalene disulfonic acid and preparation process thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS5677254A (en) * | 1979-11-27 | 1981-06-25 | Sugai Kagaku Kogyo Kk | Preparation of naphthalene-2,7-disulfonic acid |
| JPS63225352A (en) * | 1987-03-12 | 1988-09-20 | Kawasaki Steel Corp | Production of 2,7-naphthalenedisulfonic acid |
| CN101412686A (en) * | 2008-11-12 | 2009-04-22 | 扬州大学 | Method for preparing 2,7-naphthalenedisulfonate with reaction mother liquor for producing 1,6-naphthalene disulfonic acid |
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