ABSTRACT

Microwave irradiation is an effective pretreatment method for lignocellulosic biomass. Microwave-assisted inorganic salt (MAIS) pretreatment was employed to treat Napier grass (Pakchong 1) (Pennisetum purpureum) under different conditions to break down lignin from cellulose and hemicellulose in plant cell walls. Lignin and hemicellulose content were investigated under different NaCl concentrations (0.0, 1.0, and 2.0 M), and microwave irradiation was performed at 300, 450, and 800 W at three treatment times (2, 5, and 8 min). The results indicate that under pretreatment conditions of 1.0 M NaCl and 300 W for 2 min, hemicellulose content decreased by 7.93%, cellulose increased from 32.96% to 39.69% (untreated and pretreated, respectively), and lignin content decreased to 20.56%. The predicted lignin residue from the model was 13.85%, and 2 M of NaCl at 600 W for 8 min were determined to be the optimal conditions. Sample morphology following pretreatment was analyzed using scanning electron microscopy. MAIS was found to be effective and efficient for removing hemicellulose and lignin residue.

摘要

微波辐照是一种有效的木质纤维素生物质预处理方法。采用微波辅助无机盐 (MAIS) 预处理在不同条件下处理龙皮草 (Pakchong 1) ( Pennisetum purpureum )，以分解植物细胞壁中纤维素和半纤维素中的木质素。研究了不同 NaCl 浓度（0.0、1.0 和 2.0 M）下的木质素和半纤维素含量，并在三个处理时间（2、5 和 8 分钟）下以 300、450 和 800 W 进行微波照射。结果表明，在 1.0 M NaCl 和 300 W 预处理条件下 2 min，半纤维素含量降低了 7.93%，纤维素从32.96% 至 39.69%（分别为未处理和预处理），木质素含量降至 20.56%。模型预测的木质素残留量为 13.85%，2 M NaCl 在 600 W 下 8 分钟被确定为最佳条件。使用扫描电子显微镜分析预处理后的样品形态。MAIS 被发现可有效去除半纤维素和木质素残留物。