大麻芯秆烧碱-蒽醌法制浆脱木质素反应历程

Delignification Mechanism of Hemp Core Soda-AQ pulping

关键词:  大麻芯秆  脱木质素历程  木质素结构

Key Words:hemp core  delignification mechanism  lignin structure

摘要:以大麻芯秆为研究对象，通过红外（IR）和13C-NMR对大麻芯秆木质素的结构进行了研究。研究了大麻芯秆烧碱-蒽醌法蒸煮脱木质素历程。根据木质素含量和碳水化合物含量的变化规律归纳出脱木质素历程的3个阶段：初期脱木质素阶段，温度升至145℃之前，木质素脱除率在32%左右；大量脱木质素阶段，从145℃到165℃保温60 min，木质素脱除率近90%；补充脱木质素阶段，从165℃保温60 min后到蒸煮末期。通过红外（IR）和13C-NMR对碱木质素的跟踪检测，对蒸煮各阶段中木质素结构的变化进行了分析。

Abstract:The lignin of hemp core was isolated and analyzed by FT-IR and 13C-NMR. The results showed that the lignin structure of hemp core was similar to those of hardwoods. Then, delignification mechanism of hemp core Soda-AQ pulping was studied. The results showed that the delignification of Soda-AQ cooking could be divided into 3 stages: the initial delignification stage, which was from temperature beginning rising to 145℃, and its delignification rate was about 32%; the bulk delignification stage, which was the temperature from 145℃ to 165℃ and at this temperature for 60min, the total delignification rate closed to 90%; the supplementary delignification stage, which was from the end of bulk delignification stage to the end of cooking. And, in order to study the change of lignin structure in the cooking process, the alkali lignin structure was analyzed by FT-IR and 13C-NMR.