基于脱硫用栲胶的电化学行为及氧化机理  

Electrochemical behavior and oxidation mechanism of tannin extract based on desulfurization use

作　　者：薛敏华[1] 王保森[1] 付泽剑 浮建军[1] 袁园[1] 张震[1] 莫友彬 曹家兴[1] 

机构地区：[1]广西大学化学化工学院,广西南宁530004 [2]广西化工研究院,广西南宁530001

出　　处：《天然气化工—C1化学与化工》2017年第1期74-78,共5页Natural Gas Chemical Industry

基　　金：国家自然科学基金(21266003);广西教育厅自然科学基金(20110733)

摘　　要：采用电化学方法,对碱性介质中栲胶E-pH关系进行线性回归分析,并考察栲胶的循环伏安曲线。结果表明:1.00~5.00g·L^(-1)氧化栲胶E-pH回归直线的斜率在pH值为7.66~9.90范围内为-29.5,初步推断其电极反应相应得失质子数/电子数为1/2;pH值为8.9原料栲胶的循环伏安曲线分析亦表明其电极反应得失质子数和电子数分别为1、2。对栲胶法脱硫中栲胶反应机理提出:脱硫贫液中栲胶主要以T(OH)O_2氧化态存在,脱硫后的富液中栲胶主要以T(OH)_2O^-还原态存在,其电极反应式为T(OH)_2O^-+H^++2e^-=T(OH)O_2。The linear-regression analysis of E-pH and the cyclic voltammograms of tannin extract were researched in alkaline medium by electrochemical method. The results show that in the oxidized tannin extract concentration range of 1.00 to 5.00g. L·^-1 and the pH range of 7.66 to 9.90, the slope of the regression straight line of E-pH was -29.5, and so the ratio of the numbers of protons and electrons of electrode reaction was deduced preliminarily as 1/2. What＇s more, the transferred numbers of protons and electrons of plant tannin acid at pH of 8.9 was determined to be 1 and 2, respectively, by cyclic voltammetry. A reaction mechanism for the tannic extract desulfurization was proposed that tannin extract existed in T（OHO2 oxidation state form in lean solution and T（OH2O reduction state form in rich solution, and the electrode reaction is T（OH2O- ＋ H＋ ＋ 2e- = T（OHO2.

关 键 词：湿法脱硫 栲胶 氧化还原电位 循环伏安 脱硫机理 

分 类 号：O646.54[理学—物理化学] TQ546.5[理学—化学]