为了提高玉米秸秆稀硫酸预处理效果，对影响稀硫酸预处理玉米秸秆的因素如温度、时间、稀硫酸质量浓度、固液比进行了单因素实验，确定了影响参数．对实验参数采用响应曲面法对稀硫酸预处理的工艺参数进行了优化处理，使用Design Expert 8.05b软件对实验进行拟合，得到二元多次回归方程：Y ＝31.17＋4.25 X1＋1.23 X2＋0.61 X3－0.96 X1 X2－0.22 X1 X3－0.16 X2 X3－6.29 X21－2.86 X22－4.57 X23，由此得到最佳制备工艺条件为温度121.59℃，处理时间60.84min、稀硫酸的质量分数1.07％．在此条件下还原糖的得率为31．98％．在计算的最佳工艺条件下经过电子扫描显微镜（SEM ）观察发现，秸秆表面出现很多形如蜂窝状的空隙．通过红外光谱发现，木质素和半纤维素的吸收峰强度降低；通过X‐射线衍射（X RD ）表征发现稀硫酸处理60min时结晶度变化不大，说明秸秆在硫酸作用下发生了降解反应，实验获得还原糖得率为32.6％，理论和实验处理结果吻合．%In order to improve the effect of pretreating corn stover with dilute sulfuric acid each factor , including temperature ,time ,sulfuric acid concentration ,the ratio between solid and liquid ,was deter‐mined .These experimental factors were optimizated using response surface .The three factors calcula‐tion was made by Design Expert 8.05b software .The equation was obtained as follows Y=31.17+4. 25 X1 +1. 23 X2 +0. 61 X3 -0. 96 X1 X2 -0. 22 X1 X3 -0. 16 X2 X3 -6. 29 X21 -2. 86 X22 -4. 57 X23 .T he optimal condition is obtained as follow s:temperature of 121. 59℃ ,time of 60. 84min and dilute sulfuric acid concentration of 1.07% .Under the optimal condition ,the SEM results indicated that on corn stover surfaces appear many holes and some look like honeycomb voids .Infrared spectroscopy showed that the absorption peak intensity of lignin and hemicellulose reduced .XRD indicated that the corn stover degradated in sulfuric acid because crystallinity changed little after dilute sulfuric acid treatment . The reducing sugar yield is 31.98% theoretically and 32.6% experimentally ,which corresponds with each other .
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