Method for pre-processing corn straw with supercritical carbon dioxide coupled with NaOH to enhance xylose conversion efficiency through enzymatic hydrolysis

Abstract

The invention relates to the technical field ofbiomass pre-processing and comprehensive utilization of agricultural waste, and discloses a method for pre-processing corn straw with supercritical carbon dioxide coupled with NaOH to enhance xylose conversion efficiency through enzymatic hydrolysis. The method includes the following steps: (1) adding corn straw powder in an alkali solution, and obtaining a mixed material after uniform stirring; (2) performing pre-processing on the mixed materials under supercritical CO2; (3) performing suction filtration on the pre-processed mixed material through non-woven fabrics so as to obtain filtrate and filter residues; and (4) taking dried filter residues in a trisodium citrate buffer solution, adding acid xylanase in the trisodium citrate buffer solution to perform enzymatic hydrolysis for 18-24 h so as to obtain xylose. Through the innovative application of supercritical carbon dioxide coupled with NaOH to pre-process the corn straw, the efficiency of xylose preparation through enzymatic hydrolysis can be enhanced; and the pre-processing method is simple and convenient, a strengthening reagent (NaOH) is cheap and easy to obtain, processing temperature is relatively low, energy consumption can be saved, hemi-cellulose can be kept to the great extent, and enzymatic hydrolysis efficiency can be guaranteed.

Description

technical field

[0001] The invention relates to the technical field of biomass pretreatment and comprehensive utilization of agricultural waste, in particular to a method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion to xylose. Background technique

[0002] Biomass energy, as an emerging renewable energy, is an inevitable means to solve the problems of human environment, resources and energy in the future by using it to replace petrochemical resources. Biorefinery, taking the production of bioenergy as an example, its basic process is: biomass collection, pretreatment, component separation, fermentation or chemical conversion, product recovery and comprehensive utilization of by-products. Among them, biomass pretreatment occupies an important position, and to find an efficient and convenient pretreatment method requires us to continuously conduct research and experiments. [0...

Examples

Embodiment 1

[0026] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0027] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0028] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 35 ℃;

[0029] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0030] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

Embodiment 2

[0033] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0034] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0035] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 50 ℃;

[0036] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0037] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

Embodiment 3

[0040] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0041] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0042] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 70 ℃;

[0043] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0044] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

technical field

[0001] The invention relates to the technical field of biomass pretreatment and comprehensive utilization of agricultural waste, in particular to a method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion to xylose. Background technique

[0002] Biomass energy, as an emerging renewable energy, is an inevitable means to solve the problems of human environment, resources and energy in the future by using it to replace petrochemical resources. Biorefinery, taking the production of bioenergy as an example, its basic process is: biomass collection, pretreatment, component separation, fermentation or chemical conversion, product recovery and comprehensive utilization of by-products. Among them, biomass pretreatment occupies an important position, and to find an efficient and convenient pretreatment method requires us to continuously conduct research and experiments. [0...

Examples

Embodiment 1

[0026] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0027] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0028] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 35 ℃;

[0029] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0030] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

Embodiment 2

[0033] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0034] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0035] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 50 ℃;

[0036] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0037] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

Embodiment 3

[0040] The method for pretreating corn stalks with supercritical carbon dioxide coupled with NaOH to improve the efficiency of enzymatic hydrolysis and conversion of xylose comprises the following steps:

[0041] (1) After crushing, washing and drying corn stalks to obtain corn stalk powder, take 50g of corn stalk powder and add it to 500ml of 1wt% NaOH solution, stir evenly to obtain a mixture;

[0042] (2) Put the mixture in supercritical CO 2 Pretreatment for 60 minutes under the same conditions, the pretreatment temperature is 70 ℃;

[0043] (3) Suction filter the pretreated mixture through a non-woven fabric to obtain filtrate and filter residue, use 1000ml of deionized water to wash the filter residue, put the washed filter residue into an oven at 45°C and dry for 12 hours;

[0044] (4) Get 2g dried filter residue and put it into 100ml of trisodium citrate buffer, the pH of trisodium citrate buffer is 5, and add 0.625g of acid xylanase in trisodium citrate buffer , enz...

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