【摘要】 本文以酸性HZSM-5分子筛为催化剂,利用热重分析(TGA)和热裂解-气质联用(Py-GC/MS)等技术考察了生物质的两大组分纤维素和木质素的催化热解过程.氮气气氛下慢速热解的TGA实验表明,纤维素与Kraft木质素分别于285℃和135.7℃开始热解,纤维素热解后的残留量较少,仅为初始质量的8.6%,而Kraft木质素热解后的残留量高达61.9%.氦气气氛下的Py-GC/MS实验表明,纤维素快速热解的主要产物为左旋葡聚糖(LG)、羟基乙醛和羟基丙酮,积碳率仅为5%;Kraft木质素快速热解产物主要为含有不同取代基的酚类化合物,积碳率为50%.催化快速热解的Py-GC/MS实验表明,加入酸性HZSM-5分子筛可以使生物质热解产物实现有效的加氢脱氧,大大提高了热解油中的芳烃含量.然而由于热解过程中HZSM-5分子筛失活很快,使得积碳问题更加严重,纤维素催化热解的积碳率为61%,木质素样品更是高达85%.更多还原

【Abstract】 Catalytic fast pyrolysis of the two components of biomass,cellulose and Kraft lignin were studied with acidic HZSM-5 as the catalyst. The slow pyrolysis using TGA under N2 atmosphere indicated that the thermal degradation of cellulose and Kraft lignin started at 285 ℃ and 135.7 ℃,respectively,and the residual was 8.59%(at 700 ℃)and 61.93%(at 600 ℃),respectively. The fast pyrolysis using Py-GC/MS under He atmosphere implied that levoglucosan,glycolaldehyde and hydroxyacetone were the primary pyrolysis products of cellulose,and the char only account for 5%.Phenols were the main pyrolysis products of Kraft lignin and the char account for 50%. After Catalytic upgrading using HZSM-5,the main pyrolysis vapors transformed into arenes. However,it makes severe char formation after using HZSM-5(61% for cellulose and 85% for Kraft lignin).更多还原