CN110981681B - Method for purifying chromatographically pure heptane - Google Patents
Method for purifying chromatographically pure heptane Download PDFInfo
- Publication number
- CN110981681B CN110981681B CN201911037724.2A CN201911037724A CN110981681B CN 110981681 B CN110981681 B CN 110981681B CN 201911037724 A CN201911037724 A CN 201911037724A CN 110981681 B CN110981681 B CN 110981681B
- Authority
- CN
- China
- Prior art keywords
- heptane
- graphene oxide
- drying
- impurities
- chromatographic
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/005—Processes comprising at least two steps in series
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/02—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
- B01J20/20—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
- B01J20/24—Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28002—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their physical properties
- B01J20/28011—Other properties, e.g. density, crush strength
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28054—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their surface properties or porosity
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/12—Purification; Separation; Use of additives by adsorption, i.e. purification or separation of hydrocarbons with the aid of solids, e.g. with ion-exchangers
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/148—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Water Supply & Treatment (AREA)
- General Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Treatment Of Liquids With Adsorbents In General (AREA)
Abstract
The invention relates to a method for purifying chromatographic n-heptane, which comprises the steps of putting an n-heptane raw material into an ultraviolet radiation reaction kettle, and utilizing ultraviolet radiation under 185nm wavelength; adsorbing and removing impurities by using a chitosan-graphene oxide composite material; dehydrating and drying by anhydrous calcium oxide; the impurities are removed by distillation and rectification to obtain the chromatographic n-heptane. The innovation of the invention is that ultraviolet rays with the wavelength of 185nm are selected to radiate an oxidant to generate hydroxyl radicals, organic impurities are oxidized and decomposed by utilizing the strong oxidizing property of the hydroxyl radicals, the oxidizing effect is good, the speed is high, the period is short, and the like, in addition, the chitosan-graphene oxide composite adsorbing material is adopted to adsorb and remove impurities, the aggregation of graphene oxide is reduced, the specific surface area is increased, the adsorption performance is greatly improved, the purity of the n-heptane product obtained by the purification process is more than 99.4%, the moisture content is less than 0.01%, and the yield is higher than 92%.
Description
Technical Field
The invention belongs to the field of chemical reagents, relates to a purification technology, and particularly relates to a method for purifying chromatographically pure heptane.
Background
N-heptane is one of the solvents widely used in modern industry, and is mainly used as a standard substance for measuring octane number, a standard substance for chromatographic analysis, an extractant for animal and vegetable oil and fat, a quick-drying rubber adhesive, a rubber solvent, cosmetics and a solvent for cleaning paint, paint and printer parts. The method is widely applied to the fields of medicine, chemical industry, high polymer materials, rubber industry, food analysis and other industries.
The heptane with pure chromatogram has high requirement on purity, and has strict requirements on moisture, acidity, evaporation residue, ultraviolet absorption and the like, and belongs to the field of high-purity reagents. With the continuous development of scientific technology, the application of the chromatographic n-heptane is more and more extensive, the quality requirement is higher and higher, in order to meet the requirements of scientific research, improve the production process level of the chromatographic n-heptane, change the monopoly phenomenon of imported reagents, specially research a purification method of the chromatographic pure heptane, change the phenomena of low content, high ultraviolet absorption, high moisture, more solid particles, low yield and the like in the existing process level, and meet the use requirements of users.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a novel method for purifying chromatographically pure heptane, and the innovation is that an oxidant is radiated by ultraviolet rays with the wavelength of 185nm to generate hydroxyl radicals, organic impurities are subjected to oxidative decomposition by utilizing the strong oxidizing property of the hydroxyl radicals, the oxidation effect is good, the speed is high, the period is short, and the like, in addition, a chitosan-graphene oxide composite adsorbing material is adopted for adsorbing and removing impurities, the graphene oxide is modified by the composite material, the aggregation of the graphene oxide is reduced, the specific surface area is increased, the adsorption performance is greatly improved, and the purity of an n-heptane product obtained by the purification process is more than 99.4 percent, and the moisture is less than 0.01 percent.
The technical problem to be solved by the invention is realized by adopting the following technical scheme:
a method for purifying chromatographic n-heptane comprises the following steps:
(1) putting a n-heptane raw material into an ultraviolet irradiation reaction kettle, irradiating by using ultraviolet rays with a wavelength of 185nm, and carrying out oxidative decomposition on impurities in the n-heptane raw material by using the strong oxidizing property of generated hydroxyl radicals;
(2) adsorbing and removing impurities by using a chitosan-graphene oxide composite material;
(3) dehydrating and drying by anhydrous calcium oxide;
(4) removing low boiling impurities by distillation;
(5) removing impurities by rectification;
(6) and rectifying to obtain the chromatographic n-heptane.
And in the step (1), the n-heptane raw material is thrown into an ultraviolet irradiation reaction kettle, a hydrogen peroxide liquid oxidant is added according to 0.3-0.5% of the mass ratio of the n-heptane raw material, and the reaction is carried out for 0.5-1.5 h by utilizing 185nm ultraviolet irradiation.
Moreover, the preparation method of the chitosan-graphene oxide composite material in the step (2) comprises the following steps: adding 20g of graphene oxide into 10L of water, performing ultrasonic dispersion for 120min, adding 10g of chitosan into 3% glacial acetic acid, stirring until the graphene oxide is dissolved, adding the graphene oxide suspension, continuing performing ultrasonic treatment on the mixed solution for 60min, adding 500mL of epoxy chloropropane, stirring at 50 ℃ for reaction for 1h, adding a certain amount of sodium hydroxide, adjusting the pH to 11, continuing stirring for reaction for 4h, centrifuging the product, repeatedly washing with water until the supernatant is neutral, centrifuging again, and performing vacuum drying on the solid product at 60 ℃ to obtain the chitosan-graphene oxide composite material.
And (3) drying the adsorbed n-heptane feed liquid by a drying column at a flow rate of 50-100 mL/min.
And (4) adding the dried n-heptane sample liquid into a distillation kettle, adding 0.05-0.3% of calcium hydride according to the mass ratio of the n-hexane sample liquid, controlling the temperature in the kettle to be 45-55 ℃ by utilizing heat conduction oil, and the top temperature of the rectification kettle to be 40-50 ℃, and removing light-component low-boiling-point impurities.
And (5) feeding the dried feed liquid into a reaction kettle for rectification, controlling the heating temperature to be 140-200 ℃, the liquid temperature in the kettle to be 100-110 ℃, the liquid outlet temperature to be 98-99 ℃, the reflux ratio to be 10: 1-5, detecting the light absorption value moisture of the sample, and adjusting the reflux ratio to be 10: 3-8 after the sample is qualified.
Moreover, the purity of the starting material, n-heptane, was about 98%.
Furthermore, the height of the drying column used in the drying process is 1.0m, the diameter is 10cm, anhydrous calcium oxide is used as a drying agent in the drying column, the drying agent accounts for 2/3 of the drying column, and the calcium oxide used is analytically pure calcium oxide.
The invention has the advantages and positive effects that:
(1) the invention adopts an ultraviolet light catalytic oxidation technology, wherein the ultraviolet light catalytic oxidation is to radiate an oxidant by using ultraviolet light under special wavelength to generate hydroxyl free radicals, and the strong oxidizing property of the hydroxyl free radicals is used for carrying out oxidative decomposition on organic impurities. The method can oxidize benzene ring impurities and double bond impurities which affect ultraviolet absorption, and has the advantages of good oxidation effect, high speed, short period and the like. Compared with the traditional oxidants such as concentrated sulfuric acid and potassium permanganate, the oxidizing technology has the advantages of small environmental pollution, high safety and good oxidizing effect, and overcomes the defects of limited oxidizability, insufficient oxidation and the like of the conventional oxidants.
(2) The invention adopts the composite adsorbing material synthesized by chitosan (chitosan) and graphene oxide by a chemical crosslinking method, and the graphene oxide has carbon atoms with single atom thickness and honeycomb structure and very high specific surface area. The aperture of the composite material modified by compounding is obviously increased, the specific surface area is obviously increased, the polarity is enhanced, and the adsorption effect on unsaturated olefin impurities and benzene impurities is obviously enhanced. Moreover, as the chitosan and the graphene oxide have a large number of free radicals of amino, hydroxyl, carboxyl and epoxy groups, the composite adsorbing material has the advantages of the two adsorbing materials, and has good adsorbing effect on unsaturated olefin impurities and carboxylic acid impurities generated by oxidation.
(3) The invention provides a novel method for purifying chromatographically pure heptane, which is innovative in that an oxidant is radiated by ultraviolet rays with the wavelength of 185nm to generate hydroxyl radicals, organic impurities are subjected to oxidative decomposition by utilizing the strong oxidizing property of the hydroxyl radicals, the oxidation effect is good, the speed is high, the period is short, and the like, in addition, a chitosan-graphene oxide composite adsorption material is adopted for adsorption and impurity removal, the graphene oxide is modified by the composite material, the aggregation of the graphene oxide is reduced, the specific surface area is increased, the adsorption performance is greatly improved, the purity of an n-heptane product obtained by the purification process is more than 99.4%, the moisture is less than 0.01%, and the yield is more than 92%.
Detailed Description
The present invention is further illustrated by the following specific examples, which are intended to be illustrative, not limiting and are not intended to limit the scope of the invention.
Example 1
A method for purifying chromatographically pure heptane comprises the following steps:
1) and (3) oxidation: and (3) pumping the adsorbed n-heptane sample liquid into an ultraviolet irradiation reaction kettle, adding a hydrogen peroxide liquid oxidant according to 0.3-0.5% of the mass ratio of the n-heptane raw material, and carrying out ultraviolet irradiation reaction for 0.5-1.5 h.
2) Adsorption: and (3) adding the oxidized n-heptane sample liquid into the chitosan-graphene oxide composite material for adsorption and impurity removal, and controlling the adsorption speed to be 100-500 mL/min.
3) And (3) drying: and (3) drying the n-heptane feed liquid adsorbed in the step by a drying column at the flow speed of 50-100 mL/min.
4) And (3) distillation: the dried normal heptane sample liquid is injected into a distillation kettle, 0.05 to 0.3 percent of calcium hydride is added according to the mass ratio of the normal hexane sample liquid, the temperature in the kettle is controlled to be 45 to 55 ℃ by utilizing heat conduction oil, and the top temperature of the distillation kettle is controlled to be 40 to 50 ℃; removing light component low boiling point impurities.
5) And (3) rectification: and (3) putting the dried feed liquid into a reaction kettle for rectification, controlling the heating temperature to be 140-200 ℃, the liquid temperature in the kettle to be 100-110 ℃, the liquid outlet temperature to be 98-99 ℃, the reflux ratio to be 10: 1-5, detecting the light absorption value moisture of the sample, adjusting the reflux ratio to be 10: 3-8 after the product is qualified, and finally obtaining the chromatographically pure heptane product.
6) Filling nitrogen and filling: the automatic nitrogen filling is realized by adopting an automatic filling machine to obtain 4L of products, the purity of the obtained products is 99.3%, the moisture content is 0.006%, the purity and the moisture content meet the index requirements of chromatographically pure heptane, the customer requirements of chromatographically pure heptane can be met, and various detection results of the products are shown in table 1.
Table 1: detection results of various indexes of n-heptane
Example 2
A method for purifying chromatographically pure heptane comprises the following steps:
1) and (3) oxidation: and (3) pumping the adsorbed n-heptane sample liquid into an ultraviolet irradiation reaction kettle, adding a hydrogen peroxide liquid oxidant according to 0.3-0.5% of the mass ratio of the n-heptane raw material, and carrying out ultraviolet irradiation reaction for 1.0-1.5 h.
2) Adsorption: and (3) adding the oxidized n-heptane sample liquid into the chitosan-graphene oxide composite material for adsorption and impurity removal.
3) And (3) drying: and (3) drying the n-heptane feed liquid adsorbed in the step by a drying column at a flow rate of 50-100 mL/min.
4) And (3) distillation: the dried normal heptane sample liquid is injected into a distillation kettle, 0.05 to 0.3 percent of calcium hydride is added according to the mass ratio of the normal hexane sample liquid, the temperature in the kettle is controlled to be 45 to 55 ℃ by utilizing heat conduction oil, and the top temperature of the distillation kettle is controlled to be 40 to 50 ℃; removing light component low boiling point impurities.
5) And (3) rectification: and (3) putting the dried feed liquid into a reaction kettle for rectification, controlling the heating temperature to be 140-200 ℃, the temperature of the liquid in the kettle to be 100-110 ℃, the temperature of the liquid outlet to be 98-99 ℃, and the reflux ratio to be 10: 1-5, detecting the light absorption value and the moisture of the sample, adjusting the reflux ratio to be 10: 3-8 after the product is qualified, and finally obtaining the chromatographically pure heptane product.
6) Filling nitrogen and filling: the automatic nitrogen filling is realized by adopting an automatic filling machine to obtain 500mL of product, the purity of the obtained product is 99.5%, the moisture content is 0.008%, the purity meets the index requirement of the chromatogram pure heptane, the customer requirement of the chromatogram pure heptane can be met, and each detection result of the product is shown in Table 2.
Table 2: detection results of various indexes of n-heptane
Although the embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that: various substitutions, alterations and modifications are possible without departing from the spirit and scope of this disclosure and appended claims, and accordingly, the scope of this disclosure is not limited to the embodiments disclosed.
Claims (5)
1. A method for purifying chromatographic n-heptane, which is characterized in that: the method comprises the following steps:
(1) putting a n-heptane raw material into an ultraviolet irradiation reaction kettle, irradiating by using ultraviolet rays with a wavelength of 185nm, and carrying out oxidative decomposition on impurities in the n-heptane raw material by using the strong oxidizing property of generated hydroxyl radicals;
(2) adsorbing and removing impurities by using a chitosan-graphene oxide composite material;
(3) dehydrating and drying by anhydrous calcium oxide;
(4) removing low boiling impurities by distillation;
(5) removing impurities by rectification;
(6) rectifying to obtain the chromatographic n-heptane,
in the step (1), the n-heptane raw material is injected into an ultraviolet irradiation reaction kettle, hydrogen peroxide liquid oxidant is added according to the mass ratio of 0.3-0.5% of the n-heptane raw material, 185nm ultraviolet light is used for irradiation reaction for 0.5-1.5 h,
the preparation method of the chitosan-graphene oxide composite material in the step (2) comprises the following steps: adding 20g of graphene oxide into 10L of water, performing ultrasonic dispersion for 120min, adding 10g of chitosan into 3% glacial acetic acid, stirring until the graphene oxide is dissolved, adding the graphene oxide suspension, continuing performing ultrasonic treatment on the mixed solution for 60min, adding 500mL of epoxy chloropropane, performing stirring reaction at 50 ℃ for 1h, adding a certain amount of sodium hydroxide, adjusting the pH =11, continuing stirring reaction for 4h, centrifuging the product, repeatedly washing the product with water until the supernatant is neutral, performing centrifugation again, and performing vacuum drying on the solid product at 60 ℃ to obtain the chitosan-graphene oxide composite material,
and (4) pouring the dried normal heptane sample liquid into a distillation kettle, adding 0.05-0.3% of calcium hydride according to the mass ratio of the normal heptane sample liquid, and removing light-component low-boiling-point impurities by controlling the temperature in the kettle to be 45-55 ℃ and the top temperature of the distillation kettle to be 40-50 ℃ by utilizing heat conduction oil.
2. A process for the purification of chromatographic n-heptane as claimed in claim 1, characterized in that: and (3) drying the adsorbed n-heptane feed liquid by a drying column at a flow rate of 50-100 mL/min.
3. A process for the purification of chromatographic n-heptane as claimed in claim 1, characterized in that: and (5) feeding the dried feed liquid into a reaction kettle for rectification, controlling the heating temperature to be 140-200 ℃, the liquid temperature in the kettle to be 100-110 ℃, the liquid outlet temperature to be 98-99 ℃, the reflux ratio to be 10: 1-5, detecting the light absorption value and the moisture of the sample, and adjusting the reflux ratio to be 10: 3-8 after the sample is qualified.
4. A process for the purification of chromatographic n-heptane as claimed in claim 1, characterized in that: the purity of the raw material n-heptane is 98%.
5. A process for the purification of chromatographic n-heptane as claimed in claim 2, characterized in that: the height of the drying column used in the drying process is 1.0m, the diameter of the drying column is 10cm, anhydrous calcium oxide is used as a drying agent in the drying column, the drying agent accounts for 2/3 of the drying column, and the calcium oxide used is analytically pure calcium oxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911037724.2A CN110981681B (en) | 2019-10-29 | 2019-10-29 | Method for purifying chromatographically pure heptane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911037724.2A CN110981681B (en) | 2019-10-29 | 2019-10-29 | Method for purifying chromatographically pure heptane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110981681A CN110981681A (en) | 2020-04-10 |
| CN110981681B true CN110981681B (en) | 2022-09-27 |
Family
ID=70082483
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911037724.2A Active CN110981681B (en) | 2019-10-29 | 2019-10-29 | Method for purifying chromatographically pure heptane |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110981681B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115515918A (en) * | 2020-05-15 | 2022-12-23 | 株式会社德山 | Method for purifying organic compound and method for producing organic compound |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105085139A (en) * | 2014-05-16 | 2015-11-25 | 上海星可高纯溶剂有限公司 | Purification method of high-purity organic solvent n-heptane |
-
2019
- 2019-10-29 CN CN201911037724.2A patent/CN110981681B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105085139A (en) * | 2014-05-16 | 2015-11-25 | 上海星可高纯溶剂有限公司 | Purification method of high-purity organic solvent n-heptane |
Non-Patent Citations (2)
| Title |
|---|
| 氧化石墨烯／壳聚糖复合材料的制备及吸附研究进展;第23期;《材料导报》;20140531;第28卷(第23期);第60-63页 * |
| 磁性壳聚糖/氧化石墨烯吸附材料的制备及其对Pb（Ⅱ）的吸附;常会等;《冶金分析》;20181115;第38卷(第11期);第34-42页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110981681A (en) | 2020-04-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110183574B (en) | Phenylboronic acid-based polymer carrier and application thereof in selective adsorption of saccharides | |
| CN109569516B (en) | Mixed adsorbent and application thereof, and polyunsaturated fatty acid treatment method and device | |
| CN101570468B (en) | Method for preparing pesticide residue grade chromatographic ethanol | |
| CN1785990A (en) | Method of preparing tea polyphenol by resin adsorption method | |
| CN107501045B (en) | Method for separating and purifying butanetriol from fermentation liquor by using macroporous adsorption resin | |
| CN102060663A (en) | Method for preparing chromatographic pure isopropanol | |
| CN110981681B (en) | Method for purifying chromatographically pure heptane | |
| CN110981712B (en) | Method for purifying chromatographically pure acetone | |
| CN104058994A (en) | High-purity acetonitrile and method and device for preparing high-purity acetonitrile | |
| CN103030516A (en) | Purification method of coking xylene | |
| CN107304213B (en) | Method and equipment for processing poppy extract | |
| WO2022028319A1 (en) | Method for refining bio-based crude ethylene glycol | |
| CN105085138A (en) | Purification method of high-purity organic solvent n-hexane | |
| CN105085149A (en) | Purification method of high-purity organic solvent cyclohexane | |
| CN104744196A (en) | Purifying method of high-purity organic solvent n-hexane | |
| CN101143904A (en) | Method for preparing high-purity arabinogalactan | |
| KR101571511B1 (en) | Method for producing highly pure anhydrosugar alcohols with improved yield by using purification product of waste generated from crystallization procedure | |
| CN110668919B (en) | Method for purifying chromatographically pure methanol | |
| CN105085139B (en) | The method of purification of organic solvent normal heptane | |
| CN116179625A (en) | Preparation method of glucurolactone | |
| CN116354795A (en) | Purification method of chromatographic pure isopropanol | |
| CN113801134B (en) | Production process for simultaneously producing bilobalide, ginkgetin, ginkgolic polysaccharide and shikimic acid | |
| CN116891398A (en) | Purification method of chromatographic pure hexane | |
| CN110613739A (en) | Method for separating flavonoid compounds in cotton rose based on high-speed countercurrent chromatography | |
| CN102040475B (en) | Method for purifying 1,3-propylene glycol |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |