Influence of potassium on the degradative solvent extraction process of biomass components cellulose, hemicelluloses and lignin
Chaoran Duan, Qintao Sun, Xianqing Zhu, Xianqing Zhu, Mian Xu, Yun Huang, Ao Xia, Xun Zhu, Xun Zhu, Qiang Liao
Abstract
Lignocellulosic biomass mainly consists of three organic components (cellulose, hemicelluloses , and lignin) and inorganic potassium . The potential influence of potassium on the degradative solvent extraction (DSE) process of the three biomass components remains unknown and requires to be elucidated. In this study, the influence of potassium species (potassium chloride [KCl] and potassium acetate [CK]) on the DSE process of biomass organic components was systematically investigated. The results showed that KCl had a greater influence than CK on the yield distribution and chemical structure of the extraction products during the DSE process of cellulose and hemicelluloses. KCl had the most significant influence on the cellulose extract yield, reducing it from 48.96 % to 23.98 %. Both KCl and CK facilitated the decarboxylation and decarbonylation reactions of cellulose and hemicelluloses, and increased the yield of CO 2 . In addition, KCl and CK inhibited the formation of light components in extracts during the DSE process of cellulose and hemicelluloses. Both KCl and CK had limited effects on the DSE process of lignin because of lignin's thermally stable structure. The presence of KCl inhibited the aromatization reactions during the formation of cellulose extracts, and this inhibitory effect was enhanced at elevated temperatures. These findings can help elucidate the complex reaction mechanisms underlying the DSE process of biomass and provide guidance for improving the yield and quality of the extraction products by regulating the potassium content or by conducting deashing pretreatments of raw biomass .