Hg^0 removal from flue gas over different zeolites modified by Fe Cl_3  

作　　者：Hao Qi Wenqing Xu Jian Wang Li Tong Tingyu Zhu 

机构地区：[1]Beijing Engineering Research Center of Process Pollution Control, Institute of Process Engineering, Chinese Academy of Sciences [2]University of Chinese Academy of Sciences

出　　处：《Journal of Environmental Sciences》2015年第2期110-117,共8页环境科学学报（英文版）

基　　金：supported by the National Basic Research Program (973) of China (No. 2013CB430005);the National Natural Science Foundation of China (No. 21007073);the National Hi-Tech Research and Development Program (863) of China (Nos. 2013AA065404, 2013AA065501)

摘　　要：The elemental mercury removal abilities of three different zeolites（Na A, Na X, HZSM-5）impregnated with iron（Ⅲ） chloride were studied on a lab-scale fixed-bed reactor. X-ray diffraction, nitrogen adsorption porosimetry, Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy, and temperature programmed desorption（TPD） analyses were used to investigate the physicochemical properties. Results indicated that the pore structure and active chloride species on the surface of the samples are the key factors for physisorption and oxidation of Hg0, respectively. Relatively high surface area and micropore volume are beneficial to efficient mercury adsorption. The active Cl species generated on the surface of the samples were effective oxidants able to convert elemental mercury（Hg0）into oxidized mercury（Hg2＋）. The crystallization of Na Cl due to the ion exchange effect during the impregnation of Na A and Na X reduced the number of active Cl species on the surface, and restricted the physisorption of Hg0. Therefore, the Hg0 removal efficiencies of the samples were inhibited. The TPD analysis revealed that the species of mercury on the surface of Fe Cl3–HZSM-5 was mainly in the form of mercuric chloride（Hg Cl2）, while on Fe Cl3–Na X and Fe Cl3–Na A it was mainly mercuric oxide（HgO）.The elemental mercury removal abilities of three different zeolites（Na A, Na X, HZSM-5）impregnated with iron（Ⅲ） chloride were studied on a lab-scale fixed-bed reactor. X-ray diffraction, nitrogen adsorption porosimetry, Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy, and temperature programmed desorption（TPD） analyses were used to investigate the physicochemical properties. Results indicated that the pore structure and active chloride species on the surface of the samples are the key factors for physisorption and oxidation of Hg0, respectively. Relatively high surface area and micropore volume are beneficial to efficient mercury adsorption. The active Cl species generated on the surface of the samples were effective oxidants able to convert elemental mercury（Hg0）into oxidized mercury（Hg2＋）. The crystallization of Na Cl due to the ion exchange effect during the impregnation of Na A and Na X reduced the number of active Cl species on the surface, and restricted the physisorption of Hg0. Therefore, the Hg0 removal efficiencies of the samples were inhibited. The TPD analysis revealed that the species of mercury on the surface of Fe Cl3–HZSM-5 was mainly in the form of mercuric chloride（Hg Cl2）, while on Fe Cl3–Na X and Fe Cl3–Na A it was mainly mercuric oxide（HgO）.

关 键 词：MERCURY ZEOLITE Flue gas ADSORPTION Iron chloride HZSM-5 

分 类 号：X701[环境科学与工程—环境工程]