栲胶脱硫工艺中含硫副产物生成的热力学分析  

Thermodynamic Analysis of Formation of Sulfur-Containing Byproducts in Tannin Extract Desulfurization Technology

作　　者：牛艳霞[1] 凌开成[1] 盛清涛[1] 高竹青[1] 申峻[1] 

机构地区：[1]太原理工大学化学化工学院,山西太原030024

出　　处：《化肥工业》2015年第2期19-24,33,共7页Chemical Fertilizer Industry

基　　金：山西省科技攻关项目(2007032039);山西省归国留学人员资助项目(2008-27)

摘　　要：采用热力学方法研究了栲胶脱硫工艺中HS-与钒的反应机理和副反应的吉布斯自由能变。研究结果表明,脱硫液中五价钒主要是以HV2O3-7形式存在,四价钒主要是以V4O2-9形式存在。HS-与五价钒反应可瞬间生成多硫离子S2-x,然后S2-x转化为单质硫。在栲胶脱硫工艺的操作温度下,HS-和S2-x与氧气作用均可生成副产物,但S2-x比HS-活泼,更易发生副反应,且S2-x中x的值越小越活泼。在S2-x转化为副产物S2O2-3的过程中,温度越高,越有利于副反应的发生。对栲胶脱硫工艺而言,S2-x是生成副产物的活性中间产物,因此,栲胶脱硫液在进入再生系统前,应使S2-x尽可能多地转化为S8结构。The reaction mechanism of HS- with pentavalent vanadium and the Gibbs free energy change of side reaction were researched using thermodynamic method in tannin extract desulfurization technology. Study results show that in desulfurization solution the pentavalent vanadium exists mainly in the form of HV2O37^- , while the tetravalent vanadium exists mainly in the form of V4O9^2-. The reaction of HS^- with pentavalent vanadium could instantly generate polysulfide ions Sx^2-, then transformed into the elemental sulfur. At operating temperature of tannin extract desulfurization technology both HS^- and Sx^2- can react with oxygen to produce by-products. As Sx^2- is more active than HS^-, side reaction occurs more likely, moreover, the smaller the x value is, the more active the Sx^2-. In the process of Sx^2- transforming into by-products, the high temperature is favorable to side reaction. For tannin extract desulfurization technology, the polysulfide ions Sx^2- which can transformed into by- products, are active intermediate product, therefore, Sx^2- should be converted into as many S8 as possible before tannin extract desulfurization liquid entering the regeneration system.

关 键 词：栲胶 脱硫 副产物 热力学 多硫离子 

分 类 号：TQ546.5[化学工程—煤化学工程]