凹凸棒石（PG）负载V2O5催化剂脱除气态Hg0的研究  

Removal of vapor-phase Hg0 over a V2O5/PG catalyst

作　　者：白国梁 陶海兵 蔡思敏 秦伟 毛德棋 王钧伟 董彦杰 张先龙 BAI Guoliang;TAO Haibing;CAI Simin;QIN Wei;MAO Deqi;WANG Junwei;DONG Yanjie;ZHANG Xianlong(Anhui Key Laboratory of Functional Coordination Compounds,College of Chemistry and Chemical Engineering,Anqing Normal University, Anqing 246011;School of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei 230009)

机构地区：[1]安庆师范大学化学化工学院,光电磁功能材料安徽省重点实验室,安庆246011 [2]合肥工业大学化学与化工学院,合肥230009

出　　处：《环境科学学报》2019年第7期2369-2376,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.21203003,51404014);安徽省自然科学基金面上项目(No.1708085MB49);安徽省高校优秀青年人才支持计划重点项目(No.gxyqZD2017062)

摘　　要：利用凹凸棒石(PG)负载V2O5制得V2O5/PG催化剂并将其用于脱除烟气中的Hg0.在固定床反应器上研究了V2O5/PG催化剂脱除Hg0的性能,考察了反应温度、汞浓度、空速、烟气成分等对V2O5/PG脱除Hg0的影响,并利用傅里叶红外光谱、逐级化学提取和程序升温脱附实验分析了V2O5/PG上吸附Hg的形态.实验结果表明,V2O5/PG催化剂在120~210℃范围内、电厂烟气净化空速和所含汞浓度条件下具有良好的脱除Hg0的能力.烟气成分对V2O5/PG脱除Hg0的影响不同,O2具有显著的促进作用,而SO2和H2O具有一定的抑制作用,NO和CO2的作用不明显.O2、SO2和H2O共同存在时,促进了Hg0的脱除.傅里叶红外光谱、逐级化学提取和程序升温脱附实验的结果证实,V2O5/PG上吸附的汞存在不同形态,主要是Hg2+的化合物,表明Hg0在V2O5/PG上的脱除是吸附和催化氧化的共同作用,V2O5在V2O5/PG脱除Hg0的过程中起到了关键作用.A V2O5/PG catalyst, which was prepared by supporting V2O5 onto palygorskite (PG), was used to remove Hg0 from flue gas in a fixed-bed reactor. The effects of temperature, Hg0 concentration, space velocity and flue gas components on Hg0 removal over V2O5/PG were studied. Furthermore, the speciation of Hg adsorbed over V2O5/PG catalyst was also characterized by FT-IR, sequential chemical extraction (SCE) and temperature programmed desorption (TPD) experiments. The results showed that V2O5/PG catalyst had a high Hg0 removal capability in the temperature range of 120~210℃ within a space velocity and the Hg0 concentration in flue gas of coal combustion power plant. O2 showed a promotion effect on Hg0 removal over V2O5/PG while SO2 and H2O showed an inhibition effect, NO and CO2 showed no obvious effect. The co-effect of O2, SO2 and H2O promoted Hg0 removal by V2O5/PG. The results of FT-IR, SCE and TPD showed that there were different speciation of Hg over V2O5/PG and the main form was Hg2+ compounds. These confirmed that Hg0 removal over V2O5/PG was the co-effect of adsorption and oxidation, in which the catalytic oxidation activity of V2O5 played a critical role, i.e. oxidizing Hg0 to form Hg2+ compound.

关 键 词：汞 V2O5/PG 烟气 吸附 氧化 

分 类 号：X701.7[环境科学与工程—环境工程]