Preparation process of pulping prehydrolysis liquid based on advanced oxidation-nanofiltration technology

Abstract

The invention provides a preparation process of high-fermentability pulping prehydrolysis liquid based on an advanced oxidation method and a nanofiltration membrane filtering technology, aiming at solving the problem of detoxifying lignocellulose hydrolysis liquid in the prior art. The preparation process comprises the following steps: (1) preparing the pulping prehydrolysis liquid; (2) concentrating and removing sediment; (3) carrying out advanced oxidation treatment; and (4) carrying out nanofiltration treatment. The preparation process takes the prehydrolysis liquid generated by a production process of chemical mechanical pulp and dissolved pulp of a pulping papermaking industry as a treatment object; firstly, an advanced oxidation reagent is used for degrading an organic inhibitor molecule; and secondly, residual micro-molecular inhibitors in the prehydrolysis liquid are removed by using a nanofiltration membrane filtering method. The advanced oxidation and the nanofiltration membrane filtering are mutually combined to form a remarkable synergistic effect; and fermentable sugar in the prehydrolysis liquid can be kept and the micro-molecular aromatic inhibitors also can be removed. The lignocellulose hydrolysis liquid prepared by the method can be used as a fermentation carbon source and used for fermenting to produce single-cell proteins or prepare high-additional-value compounds.

Description

technical field [0001] The invention belongs to the field of bio-energy and pulping and papermaking, and in particular relates to a preparation process of a lignocellulose pulping prehydrolyzate, in particular to a method for preparing lignocellulose pulping with high-efficiency fermentation capacity by using an advanced oxidation method and an electrodialysis method Process method of prehydrolyzate. Background technique [0002] Due to the shortage of high-quality pulp and paper raw materials, the continuous increase in the price of traditional resources, the rise in labor costs and the enormous pressure brought about by global competition, traditional pulp and paper enterprises are currently facing unprecedented difficulties. The old business model of simply converting lignocellulose into pulp and paper products is no longer suitable for the existing market. Combining the pulp and paper industry with biomass refining, pre-hydrolyzing plant fiber resources before pulping c...

AI Technical Summary

Problems solved by technology

①Rotary evaporation can reduce the concentration of low-boiling organic substances in the hydrolyzate, such as acetic acid, furfural and aldehyde vanillin, etc., but new inhibitors will be produced at high temperature, resulting in a decrease in fermentation efficiency

②The application is extraction of volatile organic solvents such as ether and ethyl acetate. The hydrolyzate can remove most of the inhibitors, but it has the disadvantages of difficult recovery of organic solvents and residual organic solvents.

③ Activated carbon has strong adsorption characteristics, but the adsorption of inhibitors by activated carbon is affected by the properties of the inhibitors, the pH of the prehydrolyzed solution, the pretreatment temperature, time and the concentration of activated carbon, and the degree of removal of inhibitors is limited

④Ion exchange resin adsorption has a significant effect on the removal of weakly acidic inhibitors, but the removal effect on furfural inhibitors is limited, and this method will remove a large amount of fermentable sugars while removing inhibitors, resulting in the loss of fermentation products. Yield is greatly reduced

⑤Membrane separation can remove inhibitors such as furfural, hydroxymethylfurfural, and acetic acid in the hydrolyzate, but cannot effectively remove small molecule phenolic compounds with molecular weights similar to glucose and xylose

Although the membrane filtration method reported in this patent can remove microbial inhibitors with molecular weights smaller than hexose and pentose, such as acetic acid, formic acid, furfural, and hydroxymethylfurfural, the applicant's previous research (Sunetal, Bioresourcetechnology, 2012,) found that the nanofiltration membrane The removal efficiency of phenolic compound inhibitors in lignocellulose hydrolyzate with molecular weight greater than or close to pentose is very low, which also leads to the obvious inhibition of microbial growth and fermentation by biomass hydrolyzate after nanofiltration

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