CN115160383A - Method for oxidative degradation of lignin - Google Patents
Method for oxidative degradation of lignin Download PDFInfo
- Publication number
- CN115160383A CN115160383A CN202210962027.3A CN202210962027A CN115160383A CN 115160383 A CN115160383 A CN 115160383A CN 202210962027 A CN202210962027 A CN 202210962027A CN 115160383 A CN115160383 A CN 115160383A
- Authority
- CN
- China
- Prior art keywords
- lignin
- reaction
- salt
- oxidative degradation
- methylimidazole
- 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
- 229920005610 lignin Polymers 0.000 title claims abstract description 120
- 238000000034 method Methods 0.000 title claims abstract description 29
- 238000010525 oxidative degradation reaction Methods 0.000 title claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 69
- 238000006243 chemical reaction Methods 0.000 claims abstract description 61
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 45
- 239000007857 degradation product Substances 0.000 claims abstract description 29
- 238000003756 stirring Methods 0.000 claims abstract description 21
- -1 1-benzyl-3-methylimidazole sulfimide salt Chemical compound 0.000 claims abstract description 20
- 239000002608 ionic liquid Substances 0.000 claims abstract description 20
- 239000007788 liquid Substances 0.000 claims abstract description 12
- 239000011541 reaction mixture Substances 0.000 claims abstract description 12
- ZNNXXAURXKYLQY-UHFFFAOYSA-N 1-butyl-3-methyl-2h-imidazole;sulfuric acid Chemical compound OS(O)(=O)=O.CCCCN1CN(C)C=C1 ZNNXXAURXKYLQY-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 10
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 102
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 37
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 22
- 239000000203 mixture Substances 0.000 claims description 13
- 238000002390 rotary evaporation Methods 0.000 claims description 11
- 238000001291 vacuum drying Methods 0.000 claims description 11
- 238000005406 washing Methods 0.000 claims description 11
- 230000035484 reaction time Effects 0.000 claims description 10
- 238000004108 freeze drying Methods 0.000 claims description 9
- 238000010791 quenching Methods 0.000 claims description 9
- KXCVJPJCRAEILX-UHFFFAOYSA-M 1-butyl-3-methylimidazol-3-ium;hydrogen sulfate Chemical compound OS([O-])(=O)=O.CCCCN1C=C[N+](C)=C1 KXCVJPJCRAEILX-UHFFFAOYSA-M 0.000 claims description 6
- 239000003513 alkali Substances 0.000 claims description 6
- 238000000605 extraction Methods 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims 1
- 239000003054 catalyst Substances 0.000 abstract description 5
- 239000002904 solvent Substances 0.000 abstract description 5
- 230000000593 degrading effect Effects 0.000 abstract description 4
- 238000003912 environmental pollution Methods 0.000 abstract description 4
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000006731 degradation reaction Methods 0.000 abstract 1
- 238000000926 separation method Methods 0.000 abstract 1
- 239000012071 phase Substances 0.000 description 32
- 239000008346 aqueous phase Substances 0.000 description 7
- 239000008367 deionised water Substances 0.000 description 7
- 229910021641 deionized water Inorganic materials 0.000 description 7
- 238000003760 magnetic stirring Methods 0.000 description 7
- 239000003960 organic solvent Substances 0.000 description 7
- 230000000171 quenching effect Effects 0.000 description 7
- 230000001172 regenerating effect Effects 0.000 description 7
- 238000005303 weighing Methods 0.000 description 4
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 150000007522 mineralic acids Chemical class 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000002028 Biomass Substances 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 150000001491 aromatic compounds Chemical class 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 210000004027 cell Anatomy 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 210000004292 cytoskeleton Anatomy 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- ODLMAHJVESYWTB-UHFFFAOYSA-N propylbenzene Chemical group CCCC1=CC=CC=C1 ODLMAHJVESYWTB-UHFFFAOYSA-N 0.000 description 1
- YQUVCSBJEUQKSH-UHFFFAOYSA-N protochatechuic acid Natural products OC(=O)C1=CC=C(O)C(O)=C1 YQUVCSBJEUQKSH-UHFFFAOYSA-N 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- KCDXJAYRVLXPFO-UHFFFAOYSA-N syringaldehyde Chemical compound COC1=CC(C=O)=CC(OC)=C1O KCDXJAYRVLXPFO-UHFFFAOYSA-N 0.000 description 1
- COBXDAOIDYGHGK-UHFFFAOYSA-N syringaldehyde Natural products COC1=CC=C(C=O)C(OC)=C1O COBXDAOIDYGHGK-UHFFFAOYSA-N 0.000 description 1
- WKOLLVMJNQIZCI-UHFFFAOYSA-N vanillic acid Chemical compound COC1=CC(C(O)=O)=CC=C1O WKOLLVMJNQIZCI-UHFFFAOYSA-N 0.000 description 1
- TUUBOHWZSQXCSW-UHFFFAOYSA-N vanillic acid Natural products COC1=CC(O)=CC(C(O)=O)=C1 TUUBOHWZSQXCSW-UHFFFAOYSA-N 0.000 description 1
- MWOOGOJBHIARFG-UHFFFAOYSA-N vanillin Chemical compound COC1=CC(C=O)=CC=C1O MWOOGOJBHIARFG-UHFFFAOYSA-N 0.000 description 1
- FGQOOHJZONJGDT-UHFFFAOYSA-N vanillin Natural products COC1=CC(O)=CC(C=O)=C1 FGQOOHJZONJGDT-UHFFFAOYSA-N 0.000 description 1
- 235000012141 vanillin Nutrition 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07G—COMPOUNDS OF UNKNOWN CONSTITUTION
- C07G1/00—Lignin; Lignin 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
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0277—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature
- B01J31/0278—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre
- B01J31/0281—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre the nitrogen being a ring member
- B01J31/0284—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides comprising ionic liquids, as components in catalyst systems or catalysts per se, the ionic liquid compounds being used in the molten state at the respective reaction temperature containing nitrogen as cationic centre the nitrogen being a ring member of an aromatic ring, e.g. pyridinium
-
- 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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/19—Catalysts containing parts with different compositions
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Compounds Of Unknown Constitution (AREA)
Abstract
The invention belongs to the technical field of methods for degrading lignin, and particularly relates to a method for oxidatively degrading lignin. The method comprises the following steps: uniformly mixing 1-butyl-3-methylimidazole bisulfate and 1-benzyl-3-methylimidazole sulfimide salt to obtain homogeneous double-salt ionic liquid; adding lignin, double-salt ionic liquid and methanol into a reactor, uniformly stirring, carrying out lignin degradation reaction, carrying out solid-liquid separation on a reaction mixture after the reaction is finished, adding water into the obtained liquid to regenerate and separate out undegraded lignin, extracting an upper layer liquid to obtain a degradation product, recovering 1-butyl-3-methylimidazole bisulfate, and separating and recovering 1-benzyl-3-methylimidazole sulfimide salt and residual lignin in a lower layer liquid. The invention realizes the high-efficiency oxidative degradation of lignin; the ionic liquid is used as a solvent and a catalyst, so that the ionic liquid can be recycled and has no environmental pollution; simple process, environmental protection and strong industrial application prospect.
Description
Technical Field
The invention belongs to the technical field of methods for degrading lignin, and particularly relates to a method for oxidatively degrading lignin.
Background
Lignin is the main component constituting the cytoskeleton of plant cells and is the only renewable biomass resource with aromatic structure. As a main byproduct in processes such as papermaking and bioethanol, lignin is not fully utilized, and most of the lignin is burned as waste. Therefore, the high-value utilization of lignin is a problem with great economic value and profound social significance.
Oxidative degradation can selectively break lignin linkage (such as aryl ether bond, C-C bond), and retain most functional groups, to generate platform-type aromatic compounds (such as vanillin, syringaldehyde and vanillic acid). However, the prior art processes have limitations and have not yet formed a complete lignin oxidative degradation process. When lignin is dissolved or swelled in a solvent, the connection points between the phenylpropane units are exposed, thereby improving the conversion efficiency. Based on this, the construction of a functionalized solvent system for dissolving lignin is one of the prerequisites for achieving efficient oxidative degradation.
As a structure, a solvent-ionic liquid can be designed, and a functional system can be constructed by modulating anions and cations, so that the functional system has a unique function (solvent or catalyst) in lignin oxidative degradation. However, the oxidative degradation process of lignin in ionic liquid still has problems to be solved: the metal or inorganic acid is used as a catalyst to improve the conversion rate and selectivity, but the metal material with limited resources is consumed or the subsequent pollution problem is caused; however, the use of only pure ionic liquids as both solvent and catalyst results in longer reaction times and less efficient processes.
Therefore, a method with high reaction efficiency and environmental friendliness is sought, lignin which is a byproduct in papermaking and bioethanol is effectively degraded to prepare phenol and aromatic aldehyde compounds, and the method has great practical significance for relieving increasingly serious environmental pollution and improving future resource structures in China.
Disclosure of Invention
The invention provides a method for oxidative degradation of lignin, which uses double-salt ionic liquid (DSILs) as a raw material and has the advantages of simple process, high reaction efficiency and environmental friendliness.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a method of oxidative degradation of lignin, the method comprising the steps of:
(1) Uniformly mixing 1-butyl-3-methylimidazole hydrogen sulfate and 1-benzyl-3-methylimidazole sulfimide salt to obtain homogeneous double-salt ionic liquid; (ii) a
(2) Adding lignin, double-salt ionic liquid and methanol into a reactor, uniformly stirring, and reacting to obtain a reaction mixture;
(3) Adding water into the reaction mixture obtained in the step (2), stirring, standing and layering;
(4) Collecting the upper-layer water phase, removing water by utilizing vacuum drying, extracting by using ethyl acetate to obtain ethyl acetate containing degradation products and 1-butyl-3-methylimidazole bisulfate, and then carrying out vacuum rotary evaporation on the ethyl acetate containing the degradation products to obtain the degradation products;
(5) Adding NaOH solution into the mixture of the lower oil phase, stirring, standing and layering to obtain an upper water phase containing lignin and a lower 1-benzyl-3-methylimidazolium sulfimide salt, adding hydrochloric acid into the upper water phase containing lignin to adjust the pH of the solution to =7, separating out the regenerated lignin, washing with water, and freeze-drying to obtain the regenerated lignin;
(6) And (3) recovering the 1-butyl-3-methylimidazole hydrogensulfate obtained in the step (4) and the 1-benzyl-3-methylimidazole sulfimide salt obtained in the step (5).
In the above technical solution, further, the lignin is alkali lignin.
In the above technical solution, further, in the step (2), the reaction conditions are: initial O 2 The pressure is 1-15MPa, the reaction temperature is 80-200 ℃, and the reaction time is 0.5-5.0h.
In the above technical solution, further, in the step (2), the mass ratio of methanol to the double-salt ionic liquid is (0.1-10): 1; the solid-liquid mass ratio of the lignin to the mixture of the double-salt ionic liquid and the methanol is 1: (10-50).
In the above technical scheme, further, after the reaction in the step (2) is finished, the reactor is placed in a cold water bath to quench the reaction.
In the above technical solution, further, in the step (4), the vacuum drying temperature is 60 ℃ and the time is 24 hours; the extraction times are 3-10 times; the temperature of the vacuum rotary evaporation was 40 ℃.
In the above technical solution, further, in the step (5), the amount of the added NaOH solution is 20 to 40 times of the amount of the mixture of the 1-benzyl-3-methylimidazolium sulfonimide salt and the regenerated lignin, and the concentration of the NaOH solution is 0.1mol/L; the concentration of the hydrochloric acid is 0.1mol/L; the number of washing times is 3-6.
Compared with the prior art, the invention has the following beneficial effects:
1. compared with single ionic liquid, the double-salt ionic liquid has higher reaction efficiency;
2. the ionic liquid has good recovery effect and can be recycled for multiple times;
3. the addition of the methanol increases the solubility of the lignin and improves the reaction efficiency;
4. the invention has simple process, and avoids environmental pollution and consumption of limited resources caused by using inorganic acid or metal as a catalyst.
In conclusion, the invention realizes the efficient oxidative degradation of lignin, and the degradation products of phenol and aromatic aldehyde compounds can be used in various life and production processes, thereby having high economic benefit. The double-salt ionic liquid system used in the invention is non-volatile, can be recycled, has no environmental pollution, and has very strong industrial application prospect.
Detailed Description
The following non-limiting examples will allow one of ordinary skill in the art to more fully understand the present invention, but are not intended to limit the invention in any way.
Example 1
(1) 1-butyl-3-methylimidazolium hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to the mass ratio of 2;
(2) Respectively weighing 3g of DSILs, 7mL of methanol and 0.5g (solid-to-liquid ratio is about 1: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3h, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving in water [ BzC ] 1 im]NTf 2 And regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃, and removing the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhering to lignin and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs to obtain upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 64.7 +/-0.7 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 2
(1) 1-butyl-3-methylimidazolium hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) 3g of DSILs, 7mL of methanol and 0.25g of alkali lignin (the solid-to-liquid ratio is about 1: 40) are respectively weighed in a 50mL polytetrafluoroethylene lining, stirred at room temperature until the alkali lignin is completely dissolved, and then the lining is placed in a stainless steel high-pressure reaction kettle, wherein the reaction conditions are as follows: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3h, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving in water [ BzC ] 1 im]NTf 2 And regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate containing degradation product and[C 4 C 1 im]HSO 4 then, carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃ to remove the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhering to lignin and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs to obtain upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion of lignin was 70.8. + -. 1.5wt%. (ii) a
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 3
(1) 1-butyl-3-methylimidazole hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) 3g of DSILs, 7mL of methanol and 1g of alkali lignin (the solid-to-liquid ratio is about 1: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3 hours, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving in water [ BzC ] 1 im]NTf 2 And regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then, carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃ to remove the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhering to lignin and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs to obtain upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 50.4 +/-0.3 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 4
(1) 1-butyl-3-methylimidazolium hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) Respectively weighing 8g of DSILs, 2mL of methanol and 0.25g (solid-to-liquid ratio is about 1: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3 hours, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL of deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, and regenerating and separating out undegraded lignin without degradingWater soluble [ BzC 1 im]NTf 2 With regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃, and removing the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhered to lignin, and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs, and collecting upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 50.4 +/-0.3 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 5
(1) 1-butyl-3-methylimidazole hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) Respectively weighing 7g of DSILs, 3mL of methanol and 0.25g (solid-to-liquid ratio is about 1: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3 hours, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving in water [ BzC ] 1 im]NTf 2 With regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting the upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃, and removing the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhered to lignin, and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs, and collecting upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 58.7 +/-1.3 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 6
(1) 1-butyl-3-methylimidazolium hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) Respectively weighing 5g of DSILs, 5mL of methanol and 0.25g (solid-to-liquid ratio is about 1: initial O 2 The pressure is 1.15MPa,The reaction temperature is 150 ℃, the reaction time is 3 hours, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving in water [ BzC ] 1 im]NTf 2 And regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃, and removing the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhering to lignin and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs to obtain upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 70.7 +/-0.9 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Example 7
(1) 1-butyl-3-methylimidazolium hydrogen sulfate ([ C ] 4 C 1 im]HSO 4 ) And 1-benzyl-3-methylimidazolium sulfonimide salt ([ BzC) 1 im]NTf 2 ) Uniformly mixing according to a mass ratio of 2;
(2) Separately, 4g of DSILs, 6mL of methanol and 0.25g (about 1/1Stirring the ethylene lining at room temperature until alkali lignin is completely dissolved, and then putting the lining into a stainless steel high-pressure reaction kettle, wherein the reaction conditions are as follows: initial O 2 The pressure is 1.15MPa, the reaction temperature is 150 ℃, the reaction time is 3 hours, the magnetic stirring speed of the reaction kettle is 600rpm, and after the reaction is finished, the reaction kettle is immediately placed in a cold water bath for quenching reaction;
(3) Adding 80mL of deionized water into the reaction mixture, stirring for 20min, standing for 20min until obvious layering occurs, regenerating and separating out undegraded lignin, and dissolving the undegraded lignin in water-insoluble [ BzC ] 1 im]NTf 2 And regenerated lignin in the lower layer, [ C ] 4 C 1 im]HSO 4 Dissolved in water (upper layer);
(4) Collecting the upper water phase, vacuum drying to remove water (60 deg.C, 24 hr), and continuously extracting with Ethyl Acetate (EA) for 5 times to obtain ethyl acetate and [ C ] containing degradation product 4 C 1 im]HSO 4 Then, carrying out vacuum rotary evaporation on ethyl acetate containing the degradation product at 40 ℃ to remove the organic solvent to obtain the degradation product;
(5) The lower oil phase is [ BzC 1 im]NTf 2 In admixture with regenerated lignin, due to [ BzC 1 im]NTf 2 Easily adhering to lignin and difficult to separate and recover, adding 40mL NaOH solution (0.1 mol/L) into the lower oil phase mixture, stirring for 20min, standing for 20min until obvious layering occurs to obtain upper water phase containing lignin and lower [ BzC ] layer 1 im]NTf 2 Adding 0.1mol/L hydrochloric acid into the upper aqueous phase containing lignin to adjust the pH of the solution to be =7, separating out regenerated lignin, washing with water for 6 times, and freeze-drying to obtain regenerated lignin; the conversion rate of the lignin is 64.7 +/-0.7 wt%;
(6) Recovering [ C ] obtained in step (4) 4 C 1 im]HSO 4 And [ BzC ] obtained in the step (5) 1 im]NTf 2 。
Examples 8 to 14
The steps and materials of examples 8 to 14, etc. were the same as those of example 2 except that [ C ] was used 4 C 1 im]HSO 4 And [ BzC 1 im]NTf 2 The mass ratio of (a) is different, see the parameters listed in the table below.
TABLE 1
Examples 15 to 21
The procedures and materials, etc. of examples 15-21 were the same as in example 2, except for the parameters listed in the following table.
TABLE 2
Claims (8)
1. A method for oxidative degradation of lignin, comprising the steps of:
(1) Uniformly mixing 1-butyl-3-methylimidazole bisulfate and 1-benzyl-3-methylimidazole sulfimide salt to obtain homogeneous double-salt ionic liquid;
(2) Adding lignin, double-salt ionic liquid and methanol into a reactor, uniformly stirring, and reacting to obtain a reaction mixture;
(3) Adding water into the reaction mixture obtained in the step (2), stirring, standing and layering;
(4) Collecting the upper-layer water phase, removing water by utilizing vacuum drying, extracting by using ethyl acetate to obtain ethyl acetate containing degradation products and 1-butyl-3-methylimidazole bisulfate, and then carrying out vacuum rotary evaporation on the ethyl acetate containing the degradation products to obtain the degradation products;
(5) Adding NaOH solution into the mixture of the lower oil phase, stirring, standing and layering to obtain an upper water phase containing lignin and a lower 1-benzyl-3-methylimidazolium sulfimide salt, adding hydrochloric acid into the upper water phase containing lignin to adjust the pH of the solution to =7, separating out the regenerated lignin, washing with water, and freeze-drying to obtain the regenerated lignin;
(6) And (5) recovering the 1-butyl-3-methylimidazole bisulfate obtained in the step (4) and the 1-benzyl-3-methylimidazole sulfimide salt obtained in the step (5).
2. The method of oxidative degradation of lignin according to claim 1, wherein said lignin is alkali lignin.
3. The method for oxidative degradation of lignin according to claim 1, wherein in the step (1), the mass ratio of 1-butyl-3-methylimidazolium hydrogen sulfate to 1-benzyl-3-methylimidazolium sulfonimide salt is (0.1-10): 1.
4. the method for oxidative degradation of lignin according to claim 1, wherein in the step (2), the reaction conditions are: initial O 2 The pressure is 1-15MPa, the reaction temperature is 80-200 ℃, and the reaction time is 0.5-5.0h.
5. The method for oxidative degradation of lignin according to claim 1, wherein in the step (2), the mass ratio of methanol to double-salt ionic liquid is (0.1-10): 1;
the solid-liquid mass ratio of the lignin to the mixture of the double-salt ionic liquid and the methanol is 1: (10-50).
6. The method for oxidative degradation of lignin according to claim 1, wherein after the reaction of step (2), the reactor is placed in a cold water bath to quench the reaction.
7. The method for oxidative degradation of lignin according to claim 1, wherein in the step (4), the vacuum drying temperature is 60 ℃ and the time is 24h;
the extraction times are 3-10 times;
the temperature of the vacuum rotary evaporation was 40 ℃.
8. The method for oxidative degradation of lignin according to claim 1, wherein in the step (5), naOH solution is added in an amount of 20-40 times of the mass of the mixture of 1-benzyl-3-methylimidazolinide salt and regenerated lignin, and the concentration of NaOH solution is 0.1mol/L;
the concentration of the hydrochloric acid is 0.1mol/L;
the number of washing times is 3-6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210962027.3A CN115160383A (en) | 2022-08-11 | 2022-08-11 | Method for oxidative degradation of lignin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210962027.3A CN115160383A (en) | 2022-08-11 | 2022-08-11 | Method for oxidative degradation of lignin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115160383A true CN115160383A (en) | 2022-10-11 |
Family
ID=83478778
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210962027.3A Pending CN115160383A (en) | 2022-08-11 | 2022-08-11 | Method for oxidative degradation of lignin |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115160383A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101712698A (en) * | 2009-11-25 | 2010-05-26 | 大连工业大学 | Ionic liquid based method for extracting lignin by two-liquid-phase system |
| CN103467750A (en) * | 2013-07-29 | 2013-12-25 | 北京林业大学 | Degradation method for lignin |
| JP2015003955A (en) * | 2013-06-19 | 2015-01-08 | 独立行政法人産業技術総合研究所 | Method of decomposing lignin |
| CN105316375A (en) * | 2014-07-23 | 2016-02-10 | 中国科学院大连化学物理研究所 | Method used for pretreatment of biomass with protic/nonprotic type composite ionic liquid |
| CN106752100A (en) * | 2016-10-21 | 2017-05-31 | 青阳县金山粉业有限公司 | Modified morphology controllable nano-calcium carbonate powder of a kind of compound alkali lignin APEO activating agent and preparation method thereof |
| US20200181058A1 (en) * | 2017-08-31 | 2020-06-11 | South China University Of Technology | Method for Preparing P-Hydroxycinnamate by Using Ionic Liquid for Catalytic Lignin Depolymerization |
| CN113999269A (en) * | 2021-12-09 | 2022-02-01 | 中国矿业大学 | Method for promoting extraction of lignin in straws and catalytic preparation of levulinic acid and ethyl ester thereof by using ammonium-based Bronsted acidic ionic liquid |
-
2022
- 2022-08-11 CN CN202210962027.3A patent/CN115160383A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101712698A (en) * | 2009-11-25 | 2010-05-26 | 大连工业大学 | Ionic liquid based method for extracting lignin by two-liquid-phase system |
| JP2015003955A (en) * | 2013-06-19 | 2015-01-08 | 独立行政法人産業技術総合研究所 | Method of decomposing lignin |
| CN103467750A (en) * | 2013-07-29 | 2013-12-25 | 北京林业大学 | Degradation method for lignin |
| CN105316375A (en) * | 2014-07-23 | 2016-02-10 | 中国科学院大连化学物理研究所 | Method used for pretreatment of biomass with protic/nonprotic type composite ionic liquid |
| CN106752100A (en) * | 2016-10-21 | 2017-05-31 | 青阳县金山粉业有限公司 | Modified morphology controllable nano-calcium carbonate powder of a kind of compound alkali lignin APEO activating agent and preparation method thereof |
| US20200181058A1 (en) * | 2017-08-31 | 2020-06-11 | South China University Of Technology | Method for Preparing P-Hydroxycinnamate by Using Ionic Liquid for Catalytic Lignin Depolymerization |
| CN113999269A (en) * | 2021-12-09 | 2022-02-01 | 中国矿业大学 | Method for promoting extraction of lignin in straws and catalytic preparation of levulinic acid and ethyl ester thereof by using ammonium-based Bronsted acidic ionic liquid |
Non-Patent Citations (2)
| Title |
|---|
| YINGYING YANG等: "Free radical reaction promoted by ionic liquid: a route for metal-free oxidation depolymerization of lignin model compound and lignin", 《ROYAL SOCIETY OF CHEMISTRY》 * |
| 康莹: "离子液体体系中木质素转化及机理研究", 《中国博士学位论文全文数据库工程科技Ⅰ辑（月刊）》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112973701B (en) | Iron-sodium carbon material catalyst and preparation method and application thereof | |
| CN101774730B (en) | Intermediate waste water treatment method of quinacridone pigment and modified macroporous absorbent resin used by method | |
| CN102321681B (en) | Method and device for preparing gallic acid | |
| US20220395818A1 (en) | Carbon-based solid acid catalyst, preparation method of catalyst, and application to hydrothermal conversion of biomass | |
| CN106362804A (en) | Magnetic carbon-based solid acid catalyst as well as preparation method and application thereof | |
| CN114272932B (en) | Nickel-cerium biochar catalyst and preparation method and application thereof | |
| CN110004756B (en) | Method for separating components of wood fiber biomass | |
| Xu et al. | Review on the oxidative catalysis methods of converting lignin into vanillin | |
| CN109675550B (en) | Molybdenum-boron/sepiolite catalyst and preparation method and application thereof | |
| CN111892490A (en) | Ce4+Method for preparing beta-menadione and its derivative menadione sodium bisulfite as oxidant | |
| CN113289692B (en) | Magnetic biomass solid catalyst and preparation and application thereof | |
| CN107556168A (en) | A kind of depolymerization method of lignin | |
| CN113880888A (en) | Method for efficiently catalyzing, transferring and hydro-depolymerizing lignin under mild conditions | |
| CN115160383A (en) | Method for oxidative degradation of lignin | |
| CN101792611A (en) | Integrated method for catalyzing condensation reaction of bromamine acid by using solid acid and degrading waste water produced by condensation reaction | |
| CN108250049B (en) | Synthesis method of bisphenol fluorene | |
| CN104177447A (en) | Method for preparing phenolic chemicals by catalyzing degradation of lignin with carbon-based solid acid | |
| CN115232176A (en) | Method for extracting lignin by using ternary eutectic solvent | |
| CN102010369A (en) | Method for continuously preparing 2,2,4-trimethyl-1,2-dihydride quinoline | |
| CN109369367B (en) | Method for preparing 4- (3-hydroxyphenyl) -4-oxobutyric acid from lignin | |
| CN113430022A (en) | Method for preparing sodium polystyrene sulfonate by sulfonating waste polystyrene and application of sodium polystyrene sulfonate in coal water slurry | |
| CN107840774B (en) | Method for preparing small-molecule organic compound by catalyzing lignin degradation with solid acid | |
| CN112500296A (en) | Amantadine hydrochloride and preparation method thereof | |
| CN218596229U (en) | Device for extracting butyl glycolate from organic wastewater | |
| CN103910766A (en) | Preparation method for poplar acetic acid lignin through separation and purification |
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 |