氧脱木素过程中氧自由基的产生及其脱木素选择性  

Formation of Oxygen Radicals and Their Selectivity Reaction with Lignin and Carbohydrates in Oxygen Delignification:A Review

作　　者：刘瑞恒[1] 付时雨[1] 詹怀宇[1] 

机构地区：[1]华南理工大学制浆造纸工程国家重点实验室,广东广州510640

出　　处：《中国造纸学报》2008年第1期90-94,共5页Transactions of China Pulp and Paper

基　　金：国家自然科学基金(批准号:20477046)资助

摘　　要：氧脱木素是一个包含有多种活性氧参与的复杂的反应过程。O2在木素、碱液以及金属离子的共同作用下逐步被还原为O2-·、HO·、H2O2等活性氧。HO·与O2-·是氧脱木素过程中两种主要自由基,在脱木素过程中发挥协同作用使得木素大分子降解并溶出。氧脱木素选择性由碳水化合物的降解程度以及木素脱除率决定。HO.的强氧化性是造成碳水化合物降解的主要原因;联苯结构、对羟基苯结构等"惰性"木素单元不易降解溶出以及LCC连接、碳水化合物的结晶结构对O2及氧自由基的阻碍作用,是限制木素脱除的主要原因。Oxygen delignification is a complex process in which several active oxygen species take part in. 02 are gradually reduced to O2^-·、HO·、H2O2 etc by the combining effect of lignin, alkaline solution and metal ions. HO· and O2^-·are the main oxygen radicals in oxygen delig- nification. They have different reaction with lignin and their synergism makes lignin degrade and even dissolve. The selectivity of oxygen del- ignification is dependent on the degradation of carbohydrates and the ratio of lignin removal. HO-has strong oxidizability and causes carbohy- drates degradation. 5-5＇diphenyl and p-hydroxybenzene stlaacture are inert and difficult to be removed; LCC compound and the crystal structure of carbohydrate are the main obstacles to lignin removal.

关 键 词：氧脱水素 羟基自由基 超氧阴离子自由基 选择性 

分 类 号：TS71[轻工技术与工程—制浆造纸工程]