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Biomass energy development and utilization of effective measures to alleviate the current energy crisis and pressure on the environment and building a sustainable energy system. Biomass hydrolysis technology for biomass conversion to sugars and further fuel alcohol fermentation Preparation of liquid fuel or other high value-added chemical raw materials. Review biomass pretreatment and acid hydrolysis process based on Yang wood chips and corn stalks as raw material, the process of acid hydrolysis process as well as the purification of the hydrolyzate. The main contents and results of the study are summarized as follows: Young sawdust concentrated sulfuric acid hydrolysis process and dilute sulfuric acid hydrolysis process, examines its influencing factors: acid mass concentration, hydrolysis time, hydrolysis temperature, the ratio of liquid to solid hydrolysis. Experimental results show that when the acid concentration of 70%, hydrolysis temperature 60 ° C, and the the hydrolysis time 2h, liquid to solid ratio of 10. Sugar conversion rate of 96.4%. When the hydrolysis temperature of 200 ° C, sulfuric acid concentration of 2.5%, the hydrolysis time 30min, the liquid to solid ratio of 10, the hydrolysis of sugar conversion rate of 64.5%. Yang sawdust concentrated acid hydrolysis kinetics of Yang sawdust, a dynamic model of concentrated sulfuric acid hydrolysis of cellulosic feedstocks. Young sawdust low temperature dilute acid hydrolysis study, the effects of hydrolysis temperature, hydrolysis time, the secondary hydrolysis time Hydrolysis. The study showed that the optimal hydrolysis conditions: temperature 95 ° C, 0.5h time. The secondary hydrolysis time is 2h, sugar conversion rate up to 61.9%. The method has the advantage of reducing the amount of sulfuric acid, reduce environmental pollution, and reduce production costs. Hydrolysis of concentrated sulfuric acid and dilute sulfuric acid hydrolysis of corn stover, corn stalks concentrated sulfuric acid hydrolysis conditions: sulfuric acid concentration of 70%, hydrolysis temperature of 55 ° C, hydrolysis time of 2h. Dilute sulfuric acid hydrolysis conditions: sulfuric acid concentration of 1%, hydrolysis temperature of 160 ° C, hydrolysis time of 60 min. Dilute sulfuric acid hydrolysis of various factors on the size of the Hydrolysis: hydrolysis temperature, hydrolysis time, the concentration of sulfate. Investigated the influence of the temperature on the corn stalk hydrolysis of cellulose and hemicellulose, the results show that, at a hydrolysis temperature of 120 ° C, mainly for hemicellulose hydrolysis, and its hydrolysis was 93.7%. Cellulose hydrolysis rate 19.7%. Dilute acid hydrolysis of corn stover can be the first stage of the two-step hydrolysis method hydrolysis temperature of 120 ° C, 1% of H2SO4 hydrolysis time 60 min. The second phase of the hydrolysis temperature of 160 ℃, hydrolysis time of 60 min, 1% of the mass concentration of sulfate, liquid-solid 10. Determination of the two-step hydrolysis of total sugar conversion rate of 87.7%. Hydrolyzate purification systems research investigated macroporous resin anion exchange resin, cation exchange resin performance. The studies show that the macroporous resin, anion exchange resin, cation exchange resin, the best working bed volume ratio: 25 times the bed volume, 25 times, 45 times of the bed volume of bed volume. The mixed resin bed on the hydrolyzate for processing, its bed volume ratio of 1:1:2. By purifying treatment can get rid of the Hydrolysate salts of 95 ~ 98%, 70% to 90% of organic color bodies.
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