文献类型：期刊文献

中文题名：稻草NH_4OH-KOH蒸煮反应历程和动力学研究

英文题名：STUDY ON REACTION MECHANISM AND KINETICS OF NH_4OH-KOHPULPING OF RICE STRAW

作者：黄国林[1];邹丽霞[2];陈中胜[2];张成芳[1]

机构：[1]华东理工大学化工工艺所,上海200237;[2]东华理工学院应用化学系,江西抚州344000

年份：2003

卷号：23

期号：1

起止页码：1

中文期刊名：林产化学与工业

外文期刊名：Chemistry and Industry of Forest Products

收录：CSTPCD;;EI(收录号：2003297554007);Scopus;CSCD:【CSCD_E2011_2012】；

语种：中文

中文关键词：稻草;NH4OH-KOH蒸煮;脱木质素

外文关键词：rice straw; NH_4OH-KOH pulping; delignification

摘要：　在合适的蒸煮工艺条件下,研究了稻草NH4OH KOH法制浆的反应历程和反应动力学。反应历程研究表明,脱木质素过程分为开始升温至100℃的大量脱木质素、100～155℃下保温45min补充脱木质素和155℃下保温45min以后的残余脱木质素3个阶段;脱硅过程分为开始升温至100℃的大量脱硅、100～155℃下整个保温的少量脱硅两个阶段,硅的脱除易于木质素的脱除。动力学研究表明,脱木质素反应对残余木质素呈表观一级,对[OH-]呈0.3级,反应活化能为35.60kJ/mol;脱硅反应对残余硅呈表观一级,对[OH-]呈0.6级,反应活化能为30.91kJ/mol。
Reaction mechanism and kinetics of NH4OHKOH pulping of rice straw were studied by pulping experiments carried out under stable and welldefined conditions.Results of study showed that three distinct delignification stages occurred during this pulping process,namely,the initial delignification stages from beginning of cooking to 100 ℃,the bulk delignification stage from 100 to 155 ℃ for 45 min and the residual delignification stage at 155 ℃ for 45 min to the cooking end.There were two silica removal stages,namely,the first stage from the beginning of cooking to 100 ℃ and the second stage from 100 ℃ to the cooking end.It was approved by experiment that removal of silica was helpful for removal of lignin.During pulping process,hydroxyls of lignin reacted with KOH and NH4OH one after another,which resulted in degradation of lignin into small molecules and dissolution in alkali solution to form ammoniacal lignin.Delignification of the initial delignification stage was found to be of pseudo first order with respect to residual lignin.Activation energy of delignification reaction was 35.60 kJ/mol.Silica removal during the first silica removal stage was found to be of pseudo first order with respect to residual silica.Activation energy of silica removal reaction was 30.91 kJ/mol.