论文部分内容阅读
采用Fe(NO3)3催化乙酸对玉米秸秆进行预处理,以提高水解反应的效率,考察了乙酸初始质量分数和预处理时间对玉米秸秆水解反应的影响。结果表明,Fe(NO3)3可有效提高乙酸预处理秸秆的水解率。当使用0.05 mol/L Fe(NO3)3催化5%乙酸预处理秸秆15min时,与单独乙酸预处理玉米秸秆相比,水解液中葡萄糖、木糖和阿拉伯糖的质量浓度分别提高了110%、250%和10%,同时秸秆中半纤维素和纤维素的水解率分别提高了49%和14%;与单独0.05 mol/L Fe(NO3)3预处理玉米秸秆相比,水解液中相应的各单糖质量浓度分别提高了131%、68%和61%。随乙酸初始质量分数增加,水解反应中各产物的质量浓度均逐渐增加。乙酸初始质量分数从1%增加到5%,水解玉米秸秆15 min时,水解液中葡萄糖、木糖和阿拉伯糖的质量浓度分别从8.67 g/L、11.68 g/L和3.19 g/L升高到11.86 g/L、13.78 g/L和3.23 g/L。延长预处理时间有利于秸秆的水解反应,但太长会导致玉米秸杆中半纤维素和纤维素的水解率增加变缓。当采用0.05 mol/L Fe(NO3)3催化5%乙酸时,预处理时间从15 min延长到60 min,半纤维素的水解率从74.7%逐渐升高到92.9%,而纤维素的水解率没有变化,稳定在26%。
Fe (NO3) 3 catalyzed acetic acid pretreatment of corn stalks to improve the efficiency of the hydrolysis reaction, the initial mass fraction of acetic acid and pretreatment time on the hydrolysis of corn stalks. The results showed that Fe (NO3) 3 could effectively improve the hydrolysis rate of straw pretreated with acetic acid. When 0.05 mol / L Fe (NO3) 3 was used to pretreat straw for 15 min with 5% acetic acid, the mass concentration of glucose, xylose and arabinose in the hydrolyzate increased by 110% 250% and 10%, respectively, while the hydrolysis rates of hemicellulose and cellulose in straw increased by 49% and 14%, respectively. Compared with the pretreatment of corn stalks with 0.05 mol / L Fe (NO3) 3 alone, Each monosaccharide mass concentration increased by 131%, 68% and 61%. With the initial mass fraction of acetic acid increasing, the mass concentration of each product in the hydrolysis reaction gradually increased. The initial mass fraction of acetic acid increased from 1% to 5%, and the mass concentrations of glucose, xylose and arabinose in the hydrolyzate increased from 8.67 g / L, 11.68 g / L and 3.19 g / L, respectively, at 15 min after hydrolyzing corn stalks To 11.86 g / L, 13.78 g / L and 3.23 g / L, respectively. Prolonging the pretreatment time is beneficial to the hydrolysis of straw, but too long will lead to the slow increase of the hydrolysis rate of hemicellulose and cellulose in corn stalks. When 0.05 mol / L Fe (NO3) 3 was used to catalyze 5% acetic acid, the pretreatment time was prolonged from 15 min to 60 min, the hydrolysis rate of hemicellulose increased from 74.7% to 92.9%, while the hydrolysis rate of cellulose No change, stable at 26%.