Optimization Of Combined Dilute Sulfuric Acid And LAT Pretreatment For Enzymatic Hydrolysis Of Corn Stover

The China’s corn crop is enormous，in this paper corn stover will be pretreated by LAT(LiquidAmonia Pretreatment), soaking in dilute sulfuric acid pretreatment and combined both to analyze theeffect of enzymatic degeatibility. Pretreatment conditions including moisture contents, temperature,time residence, ammonia loading, concentration of dilute sulfuric acid, soaking time and ratio ofsolid to liquid were varied to maximize hydrolysis yields. The experimental results are as following.(1)Optimized condition for LAT pretreatment of corn stover is:mosture content80%,temperature130℃, resident time10min. In this condition, the conversion of glucan and xylan ofcorn stover after pretreated and enzymatic hydrolysis is86.53%and84.31%, while the conversion ofuntreated corn stover is42.23%and40.50%. The conversion of glucan and xylan of pretreated cornstover has promoted by96.90%and96.57%. After mass balance, we can figure out that there will be313.2g glucose and184.6g xylan out of1000g corn stover.(2)The optimal condition of soaking in dilute sulfuric acid is as followed: concentration ofdilute sulfuric acid1.47%, solid-to-liquid ratio1:10, soaking time2h, under which comes the bestconversion of glucan and xylan. The conversion of glucan and xylan is78.38%and73.63%.303.1gglucan and177.9g xylan can be get from every1000g corn stover as mass balanced.(3)To optimize the condition of soaking in dilute sulfuric acid combined with LAT, theconditions are set as following: moisture content80%, temperature130℃, ammonia loading1.0andresident time is30min. After certain pretreatment that conducted to corn stover, it is expected toobtain384.1g glucose and189.6g xylose from1000g corn stover.(4)LAT after soaking in dilute sulfuric acid enhance delignification enzymatic hydrolysis yieldsof both glucose and xylose and acid-insoluble lignin removal was36.33%without regarding weightloss.