CN1201778A - Method for producing vanillin and syringaldehyde by catalytic oxidation of alkali lignin of sugercane residue - Google Patents
Method for producing vanillin and syringaldehyde by catalytic oxidation of alkali lignin of sugercane residue Download PDFInfo
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- CN1201778A CN1201778A CN 98113227 CN98113227A CN1201778A CN 1201778 A CN1201778 A CN 1201778A CN 98113227 CN98113227 CN 98113227 CN 98113227 A CN98113227 A CN 98113227A CN 1201778 A CN1201778 A CN 1201778A
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Abstract
A process for preparing lilacaldehyde and vanillin with alkali lignin of cane dregs includes such steps as use of acid to precipitate alkali lignin of cane dregs in waste pulp liquid, filtering, alkaline catalytic oxidization to generate low-molecular products including lilacaldehyde and vanillin, extracting with organic solvent and then with sodium hydrogen sulfite, distillation, aldehyde-ammonia complexing, recrystallization, sublimation and separation, and features use of Fe2O3.CuO or Cu type of natural mordenite and Fe2O3 as efficient catalyst to increase output rate and reduce alkali consumption.
Description
The invention relates to a method for preparing syringaldehyde and vanillin by catalytic oxidation of alkali lignin in pulp waste liquid bagasse.
Syringaldehyde and vanillin are important chemical raw materials and perfumes, and the production method is an important method for extracting vanillin from natural plant lignin besides organic synthesis, so that vanillin is successfully separated from lignin oxidation products of coniferous wood, and syringaldehyde and vanillin are separated from lignin oxidation products of deciduous wood (Can.Pat: 1040216; U.S. Pat: 2104701, 2399607, 3755456 and the like).
We research the method for producing syringaldehyde and vanillin by using pulp waste liquid bagasse alkali lignin, and the report of related papers is shown in the following: ca.123(14)173063 j; 123(10) 115824X. In the report of the above-mentioned papers, the chemical composition and preparation method of the high-efficiency catalyst used in the catalytic oxidation of bagasse alkali lignin have not been referred.
The invention uses bagasse alkali lignin rich in syringyl, guaiacyl and p-hydroxyphenyl as raw material, prepares syringaldehyde and vanillin by catalytic oxidation, firstly uses acid to precipitate the bagasse alkali lignin in the pulp waste liquid, filters the bagasse alkali lignin, then carries out alkaline catalytic oxidation to generate low molecular products of syringaldehyde and vanillin, and the like, extracts compounds of syringaldehyde and vanillin, and the like by organic solvent, and separates and purifies high-purity syringaldehyde and vanillin by means of sodium bisulfite aqueous solution extraction, vacuum distillation, aldehyde-ammonia complexation, recrystallization, sublimation, and the like, and is characterized in that a high-activity catalyst is adopted, and the dosage of the catalyst is 0.02-0.18g catalyst/g lignin; the method for producing a high-activity catalyst comprises: the following substances are activated by calcining for 2 hours at 410-420. (1) Activated Fe2O3·CuO
Mixing Fe (OH)3And Cu (OH)2According to Fe2O3Mixing CuO with the molecular ratio of 1: 1, and calcining; (2) activated Cu+2Natural mordenite
Treating natural mordenite with hydrochloric acid at 70-90 deg.C, and exchanging into H+Molding, and then using CuSO4Treating the solution at normal temperature, and exchanging the solution into Cu+2Type, high temperature calcination of zeolite catalysts can be exchanged for H+When the type is changed to Cu+2Performing molding; (3) activated Fe2O3
FeCL3Aqueous solution ofPrecipitating with ammonia water to obtain Fe (OH)3Calcining;
the invention provides a method for preparing syringaldehyde and vanillin by catalytic oxidation of bagasse alkali lignin, which comprises the following steps: firstly, extracting the bagasse alkaline lignin from the pulp waste liquid, acidifying the bagasse pulp waste liquid to pH3.5-4.0 by using 10-12% hydrochloric acid, then preserving the heat at 48-52 ℃ for 50 minutes, and filtering by using a plate-and-frame filter press to obtain a bagasse alkaline lignin wet filter cake which can be directly used for alkaline oxidation or dried at the temperature of below 60 ℃ until the water content is below 10% for storage and standby application; preparation of syringaldehyde and vanillin by catalytic oxidation of bagasse alkali lignin
The oxidation reaction is carried out in an autoclave, the catalyst prepared in the step (1) or (2) or (3) is selected, the reaction medium is an alkali solution such as a sodium hydroxide aqueous solution, the concentration is 1.6-2.4mol/L, the lignin concentration is 40-105g/L, the reaction temperature is 155-170%, the reaction pressure is 1.0-1.75MPa (gauge pressure), the reaction time is 50-110min, and the air flow is 1.0-4.0L/L solution min; the optimal conditions are that the concentration of NaOH is 2mol/L, the lignin concentration is 78g/L, the reaction temperature is 165 ℃, the reaction pressure is 1.5MPa (gauge pressure), the reaction time is 90min, and the air flow is 2.0-3.0L/L solution/min (the bagasse alkali lignin is calculated by extracting lignin by dioxane). Acidifying the oxidation product with hydrochloric acid to pH3.8-4.0, extracting with chloroform or benzene, and separating and purifying syringaldehyde and vanillin with the extractive solution. (III) separation and purification of syringaldehyde and vanillin
Evaporating the oxidation product extractive solution to dryness, dissolving with n-butanol, extracting aldehyde compounds with saturated sodium bisulfite aqueous solution, acidifying the extractive solution with sulfuric acid to pH2-3, extracting with chloroform to obtain syringaldehyde and vanillin mixture, evaporating to dryness, dissolving with methanol,
adding ammonia water, standing, filtering, precipitating to obtain syringaldehyde ammonia complex, acidifying the complex with acid to pH of 2.8-3.2 to obtain syringaldehyde crystal, and recrystallizing to obtain refined syringaldehyde; acidifying the filtrate, evaporating to remove methanol, separating out vanillin, distilling, and sublimating to obtain refined vanillin.
The method for preparing syringaldehyde and vanillin provided by the invention adopts the efficient catalyst, so that the yield of lignin oxidation products is high, the alkali consumption is low, and the method is suitable for recycling bagasse alkaline pulping waste liquid.
Example (b): preparation of bagasse alkali lignin alkaline oxidation high-activity catalysts a few high-activity catalysts were prepared by the following methods: (1) catalyst A
Natural mordenite powder is exchanged into H at 90 DEG C+Type, normal temperature exchanged to Cu+2Type, 410-420 ℃ for 2 hours. (4) Catalyst D
Natural mordenite powder is exchanged into H at 90 DEG C+Type, 410-+2And (4) molding. (5) Catalyst E
Exchanging natural mordenite powder into H at 70 DEG C+Type, normal temperature exchanged to Cu+2Type, 410-420 ℃ for 2 hours. (6) Catalyst F
FeCl is added3Preparing an aqueous solution, and then generating Fe (OH) by using ammonia water3Precipitation, then Fe (OH)3Calcining at 410-420 ℃ for 2 hours to obtain Fe2O3。
Taking the zeolite powder in a sieve fraction smaller than 80 meshes. Zeolite powder exchanged to H with 1.5M HCl+10% of CuSO for molding4Exchange of aqueous solution to Cu+2And (4) molding. The conversion exchange of the zeolite is carried out on a column.<II>Extraction of bagasse alkali lignin
25kg of bagasse pulp black liquor of the southern Guangdong sea sugar refinery is taken, the black liquor is acidified to the pH value of below 4 by using 12% hydrochloric acid, then the temperatureis kept at 45 ℃ for 50 minutes, and the black liquor is filtered by a plate-and-frame filter press to obtain 12kg of wet lignin precipitate. The results of the wet lignin assay are listed in table 1.
TABLE 1 test results of lignin filter cake of bagasse from southern sea sugar refinery
| Wet lignin filter cake water (%) | 77-78 |
| Acid precipitation solid ash (%) | 10.3 |
| Acid precipitation solid lignin (%) | 77.3 |
Wherein, the content of bagasse alkali lignin is determined by a dioxane extraction method, and each kg of extracted lignin needs to consume 1.8kg of 36 percent HCl.<III>Catalytic oxidation of bagasse alkali lignin (1) 2g of the acid precipitate of the dried bagasse alkali lignin (containing 62.8% of dioxane extracted lignin) from Dongguan sugar refinery was weighed and dissolved in 30ml of NaOH of 2mol concentration, and placed in a 0.1L reaction autoclave, and appropriate amount of CuSO was added to each autoclave4And the high activity catalysts A, B, C, D, E and F prepared in the example (I), and the like, then compressed air is introduced, the ventilation amount is 1.0-3.0L/L solution min, and the reaction is carried out for 90min underthe conditions that the gauge pressure is 1.0MPa and the temperature is 160-. Cooling the kettle, taking out the mixture, acidifying with HCl to pH4, extracting the acidic substance with 240ml chloroform for 6 times, concentrating the extractive solution, and analyzing the content of low molecular products such as vanillin and syringaldehyde with gas chromatography. Table 3 shows the milligrams of vanillin (V) and syringaldehyde (S) obtained by oxidation of absolute dry bagasse alkali lignin acid precipitate per gram under different catalyst conditions.
The data in Table 2 show that a plurality of catalysts have better catalysis effect on the alkaline oxidation of bagasse alkali lignin, and the catalysts prepared in the first step of the invention are all better than CuSO4Has high catalytic activity.
TABLE 2 amount of V and S obtained by oxidation of oven-dried bagasse alkali lignin acid precipitate per gram of Dongguan sugar refinery
| Catalyst and process for preparing same | Amount of catalyst used (mg) | Amount of oxidized product (mg) | ||
| V | S | V+S | ||
| Air (a) | / | 13.4 | 40.5 | 53.9 |
| CuSO4·5H2O | 50 | 16.9 | 42.5 | 59.4 |
| A | 50 | 20.8 | 44.7 | 65.5 |
| B | 50 | 24.6 | 47.7 | 72.3 |
| C | 200 | 23.4 | 46.6 | 70.0 |
| D | 200 | 21.9 | 50.0 | 71.9 |
| E | 200 | 21.4 | 46.1 | 67.5 |
| F | 50 | 20.8 | 46.9 | 67.7 |
(2) The experiment adopts a 0.5L autoclave reactor, and 0.78g of CuSO is weighed each time4·5H2O is used as a catalyst, and the following reaction conditions are established: the solution per liter contains 78g of bagasse alkali lignin (lignin extracted by dioxane) of the south China sea sugar refinery, the concentration of a medium NaOH is 2mol/L, the volume is 300ml, the gauge pressure of a reactor is 1.5MPa, the reaction temperature is 165 ℃, and the reaction time is 90min as a reference condition. The reaction time, reaction pressure, reaction temperature, reactant concentration and reaction medium NaOH concentration were varied respectively, and the yield changes of vanillin and syringaldehyde, which are oxidation products, were examined, and the results are shown in Table 3. The reaction is aerated with 2.0-3.0L/L solution/min.
TABLE 3 amount of V and S obtained by oxidation of alkali lignin per gram of bagasse from southern sea sugar refinery
Blank reaction conditions without catalyst were the same as the baseline reaction conditions described above.
| Oxidation conditions | Oxide yield (mg) | |||
| V | S | V+S | ||
| Reference oxidation conditions | 35.0 | 59.5 | 94.5 | |
| Change in reaction temperature ℃ | 155 | 27.8 | 46.2 | 74.0 |
| 170 | 27.9 | 47.7 | 75.6 | |
| Change of reaction time min | 50 | 30.6 | 53.6 | 84.2 |
| 110 | 28.2 | 43.1 | 71.3 | |
| Reaction medium NaOH Variation in concentration (M) | 1.6 | 21.4 | 36.8 | 58.2 |
| 2.4 | 32.4 | 53.1 | 85.5 | |
| Change in reaction pressure (MPa) | 1.00 | 19.6 | 36.7 | 56.3 |
| 1.75 | 29.5 | 43.8 | 73.3 | |
| Change in lignin concentration (g/L) | 65 | 27.2 | 45.2 | 72.4 |
| 103 | 17.6 | 30.0 | 47.6 | |
| Catalyst-free | 17.6 | 28.8 | 46.4 | |
The data in Table 3 show that the results are best for the reference reaction conditions established in this experiment. And (IV) separating and purifying syringaldehyde and vanillin, and (1) evaporating the bagasse alkali lignin alkaline oxide chloroform extract under reduced pressure to dryness. Chromatographic analysis meter
The solid content of the extract contains 27.4 percent of vanillin and 47.3 percent of syringaldehyde. Taking 100g of the solid matter, namely,
dissolving in 1L n-butanol, acidifying the solution with 50% sulfuric acid to pH3, and saturating with 4L
And extracting the solution with sodium bisulfite aqueous solution for 4 times, and vigorously shaking for 20min during extraction. Drawer
The extract is acidified to pH2-3 with 50% sulfuric acid and then extracted 6 times with 600ml chloroform
Taking the aldehyde compound. Evaporating the extract under reduced pressure to dry to obtain extract containing vanillin 30.1% and lilac
Aldehyde 52.1% 90.5g of a brown crystalline aldehyde mixture. (2) Distilling 90.5g of aldehyde compound obtained in experiment (1) under 133.3-266.6Pa and at a temperature lower than 175 ℃ to obtain 75.8g of distillate, wherein the distillate contains 31.7% of vanillin and 57.9% of syringaldehyde according to chromatographic analysis results. (3) Dissolving 75.8g of distillate containing vanillin and syringaldehyde obtained in the step (2) in 750m 190% of methanol
To the alcohol aqueous solution, 52ml of ammonia water (29% NH) was slowly dropped under stirring3) After standing, use
The precipitate obtained was filtered through a G5 glass funnel and washed twice with 120ml of 90% aqueous methanol to obtain syringaldehyde ammonia complex.
Soaking syringaldehyde ammonia complex in 300ml 30% methanol water solution, cooling with ice water bath, acidifying the mixture with 50% sulfuric acid under stirring to pH3, standing, and adding G5Filtering with a glass funnel, and washing twice with 100ml of distilled water to obtain syringaldehyde crystals. The syringaldehyde crystals were dissolved in 100ml of 90% methanol aqueous solution, and the methanol was slowly distilled off under reduced pressure to a methanol concentration of less than 30%, thereby recrystallizing syringaldehyde. Filtering off mother liquor, and adding P2O5Drying to obtain 30.5 g syringaldehyde crystals with the purity of 99.4 percent. (4) Mixing the filtrate and washing solution of syringaldehyde separated in experiment (3), acidifying with 50% sulfuric acid to pH4, evaporating under reduced pressure to remove methanol to reduce methanol concentration to below 45%, and standing to separate out vanillin as oily substance. After the oil was separated, the vanillin precipitate was distilled under a pressure of 133.3-266.6Pa and at a temperature below 160 deg.C, and the resulting fraction was sublimed to obtain 17.1 g vanillin having a purity of 98.3%.
Claims (4)
1. A method for preparing syringaldehyde and vanillin by catalytic oxidation of bagasse alkali lignin comprises the steps of precipitating and filtering the bagasse alkali lignin in paper pulp waste liquid by hydrochloric acid, carrying out catalytic oxidation on the obtained product to generate low molecular products such as syringaldehyde and vanillin, extracting the product by using an organic solvent, and separating and purifying the product by the steps of sodium bisulfite extraction, distillation, aldehyde-ammonia complexation, recrystallization and sublimation, wherein the method is characterized in that the alkali oxidation of the alkali lignin adopts a high-activity catalyst, and the dosage of the catalyst is 0.02-0.18g of catalyst per g of lignin; the preparation method of the catalyst comprises the following steps: the following substances are activated by calcining for 2 hours at 410-420.
1) Activated Fe2O3CuO Fe (OH)3And Cu (OH)2According to Fe2O3Mixing CuO and CuO at the molecular ratio of 1: 1, and calcining;
2) activated Cu+2Treating natural mordenite with hydrochloric acid at 70-90 deg.C, and exchanging into H+Molding, and then using CuSO4Treating the solution at normal temperature, and exchanging the solution into Cu+2Molding, by calcining;
3) activated Fe2O3FeCl3Aqueous solution, precipitation with aqueous ammonia, yielding Fe (OH)3And then calcining.
2. A method according to claim 1, characterized in that the acidification of the spent pulp liquor is carried out by acidification with 10-12% hydrochloric acid to a pH of 3.5-4.0 and aging at 48-52 ℃ for 50 minutes.
3. The method of claim 1, wherein the Cu is activated+2The calcination activation of natural mordenite can be exchanged into H+When the type is changed to Cu+2And (4) performing after molding.
4. The method as claimed in claim 1, wherein the concentration of the catalytic oxidation reaction medium NaOH aqueous solution of bagasse alkali lignin is 1.6-2.4mol/L, the concentration of lignin is 40-105g/L, the oxidation temperature is 155-170 ℃, the reaction pressure is 1.0-1.75MPa, the amount of air is 1.0-4.0L/L solution min, and the reaction time is 50-110 min.
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| Application Number | Priority Date | Filing Date | Title |
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| CN98113227A CN1060464C (en) | 1998-05-29 | 1998-05-29 | Method for producing vanillin and syringaldehyde by catalytic oxidation of alkali lignin of sugercane residue |
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| CN98113227A CN1060464C (en) | 1998-05-29 | 1998-05-29 | Method for producing vanillin and syringaldehyde by catalytic oxidation of alkali lignin of sugercane residue |
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| CN1201778A true CN1201778A (en) | 1998-12-16 |
| CN1060464C CN1060464C (en) | 2001-01-10 |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1127468C (en) * | 2000-09-14 | 2003-11-12 | 华南农业大学 | Process for synthesizing vanillin from alkali lignin by green chemical method |
| CN102115432A (en) * | 2010-12-30 | 2011-07-06 | 江南大学 | Method for preparing and separating p-hydroxybenzaldehyde, vanillin and syringaldehyde from lignin |
| CN102146025A (en) * | 2011-01-31 | 2011-08-10 | 江南大学 | Method for preparing syringaldehyde by oxidative degradation of lignin |
| CN102875343A (en) * | 2012-10-31 | 2013-01-16 | 南京林业大学 | Method for preparing aromatic aldehyde compound by catalyzing and degrading lignin with loaded solid acid |
| CN104910341A (en) * | 2015-06-24 | 2015-09-16 | 湖南师范大学 | Method for preparing lignin phenolic resin adhesive by treating papermaking waste liquid with microwave-CuO |
| CN105189858A (en) * | 2013-03-21 | 2015-12-23 | 日本烟草产业株式会社 | Production method for black liquor and production method for liquid containing flavoring component |
| WO2018058219A1 (en) * | 2016-09-30 | 2018-04-05 | Oxitec Participação E Gestão De Ativos Não Financeiros Ltda. | Process for treating dregs, treated dregs, use thereof, process for vulcanizing rubber, and vulcanized rubber |
| CN114570375A (en) * | 2022-03-10 | 2022-06-03 | 中国农业大学 | Hydrotalcite-based catalyst, preparation method thereof and application of hydrotalcite-based catalyst in efficient catalytic preparation of vanillin |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3755456A (en) * | 1970-11-10 | 1973-08-28 | Sterling Drug Inc | Aldehyde separation process |
| CA1040216A (en) * | 1975-09-11 | 1978-10-10 | Harry B. Marshall | Production of syringealdehyde and/or vanillin from hardwood waste pulping liquors |
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1998
- 1998-05-29 CN CN98113227A patent/CN1060464C/en not_active Expired - Fee Related
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| CN1127468C (en) * | 2000-09-14 | 2003-11-12 | 华南农业大学 | Process for synthesizing vanillin from alkali lignin by green chemical method |
| CN102115432A (en) * | 2010-12-30 | 2011-07-06 | 江南大学 | Method for preparing and separating p-hydroxybenzaldehyde, vanillin and syringaldehyde from lignin |
| CN102146025A (en) * | 2011-01-31 | 2011-08-10 | 江南大学 | Method for preparing syringaldehyde by oxidative degradation of lignin |
| CN102146025B (en) * | 2011-01-31 | 2013-06-05 | 江南大学 | Method for preparing syringaldehyde by oxidative degradation of lignin |
| CN102875343A (en) * | 2012-10-31 | 2013-01-16 | 南京林业大学 | Method for preparing aromatic aldehyde compound by catalyzing and degrading lignin with loaded solid acid |
| CN102875343B (en) * | 2012-10-31 | 2015-04-08 | 南京林业大学 | Method for preparing aromatic aldehyde compound by catalyzing and degrading lignin with loaded solid acid |
| US10851494B2 (en) | 2013-03-21 | 2020-12-01 | Japan Tobacco Inc. | Method for preparing black liquor and method for preparing flavor component-containing liquid |
| CN105189858A (en) * | 2013-03-21 | 2015-12-23 | 日本烟草产业株式会社 | Production method for black liquor and production method for liquid containing flavoring component |
| CN104910341A (en) * | 2015-06-24 | 2015-09-16 | 湖南师范大学 | Method for preparing lignin phenolic resin adhesive by treating papermaking waste liquid with microwave-CuO |
| CN110382608A (en) * | 2016-09-30 | 2019-10-25 | 奥克斯技术参与管理非金融资产有限公司 | Handle method, processed green mud, its purposes, the method for vulcanized rubber and the vulcanized rubber of green mud |
| WO2018058219A1 (en) * | 2016-09-30 | 2018-04-05 | Oxitec Participação E Gestão De Ativos Não Financeiros Ltda. | Process for treating dregs, treated dregs, use thereof, process for vulcanizing rubber, and vulcanized rubber |
| US11306436B2 (en) | 2016-09-30 | 2022-04-19 | OXITEC Participaçäo e Gesto de Ativos näo Financeiros Ltda. | Process for treating dregs, treated dregs, use thereof, process for vulcanizing rubber, and vulcanized rubber |
| CN110382608B (en) * | 2016-09-30 | 2022-05-03 | 奥克斯技术参与管理非金融资产有限公司 | Method for treating green mud, treated green mud, use thereof, method for vulcanizing rubber and vulcanized rubber |
| US11767636B2 (en) | 2016-09-30 | 2023-09-26 | Oxitec Participação E Gestão De Ativos Não Financeiros Ltda. | Process for treating dregs, treated dregs, use thereof, process for vulcanizing rubber, and vulcanized rubber |
| CN114570375A (en) * | 2022-03-10 | 2022-06-03 | 中国农业大学 | Hydrotalcite-based catalyst, preparation method thereof and application of hydrotalcite-based catalyst in efficient catalytic preparation of vanillin |
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