高温碱性H_2O_2体系中羟自由基的研究  

A Study on the Hydroxyl Radicals in High Temperature Alkali Hydrogen Peroxide System

作　　者：张曾[1] 黄干强[1] 潘光建[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,广州510640

出　　处：《中国造纸》2005年第11期5-9,共5页China Pulp & Paper

基　　金：国家自然科学基金(20276023)资助项目;广东省自然科学基金(04020024)资助项目

摘　　要：利用二甲基亚砜(DMSO)作为捕集剂对高温碱性H2O2体系中羟自由基的产生及浓度进行了分析。研究结果表明,DMSO可以有效地应用于不同温度体系中羟自由基的捕集,捕集反应的产物为甲基亚磺酸(MSA);在碱性条件下引发H2O2分解产生羟自由基的起点温度在70℃左右,随着温度上升,羟自由基浓度增加,但当温度超过130℃后,羟自由基浓度不再有明显增加;随H2O2分解时间的延长、H2O2用量的增加以及选择一定的NaOH浓度,都使羟自由基的浓度增加。The hydroxyl radicals in high temperature alkali hydrogen peroxide system were studied. Dimethyl sulfoxide （DMSO） was used as the trap- ping agent for determining the production and concentration of the radicals. The results show that dimethyl sulfoxide can be efficiently applied to capture hydroxyl radicals in different temperature system. The methane sulfinic acid （MSA） produced can react with the diazonium salt, Fast Blue BB salt, to produce diazosulfone which can be determined with spectrophotometry at the maximal absorbance of 415nm. The investigations in the range of 60℃ to 140℃ indicate that hydrogen peroxide starts to decompose and produces hydroxyl radicals under alkaline condition at the temperatm＇e around 70℃. The concentration of hydroxyl radicals goes up with the temperature increasing. However the concentration no longer increases obviously and the maximal decomposition of hydrogen peroxide may be reached when temperature is above 130℃. The yield of hydroxyl radical is gradually raised with the increase of retention time under high temperature. The decomposition reaction mostly finishes within 10min under 120℃. The radical concentration also increases with the raise of hydrogen peroxide charge and at certain concentration of sodium hydroxide.

关 键 词：羟自由基 过氧化氢 高温 二甲基亚砜 分光光度法 

分 类 号：TS713[轻工技术与工程—制浆造纸工程]