Influence of ZnCl2 solution impregnation on the surface properties of lignite semi-coke and its mercury removal performance at elevated temperature
WANG Li, CHEN Jiang-yan, ZHAO Ke, ZHANG Hua-wei
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China
The modified semi-coke (ZSC) was obtained by the pyrolysis of ZnCl2-impregnated lignite at 700℃. N2 adsorption/desorption, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the surface physical and chemical properties of original and modified semi-coke, and the gaseous elemental mercury (Hg0) removal performance of two kinds of semi-coke has been investigated in a lab-scale fixed-bed reactor. The experimental results showed that ZSC had more developed hole structure, large specific surface area and abundant C—Cl groups. The mercury removal efficiency of ZSC decreased as the adsorption temperature was raised in the temperature range of 100℃ to 360℃. Generally, the ZSC exhibited good mercury removal performance at elevated temperatures. During the chemisorption process, the Hg0 was partly oxidized to HgCl or HgCl2 by C—Cl groups, and the others reacted with oxygen contained functional groups on the surface of semi-coke to generate HgO simultaneously. Finally, the Hg0 was captured in the form of HgCl2 or HgO on the surface of semi-coke.
王力, 陈江艳, 赵可, 张华伟. ZnCl2溶液对褐煤半焦表面性质及其中高温脱汞性能的影响[J]. 中国环境科学, 2016, 36(3): 702-708.
WANG Li, CHEN Jiang-yan, ZHAO Ke, ZHANG Hua-wei. Influence of ZnCl2 solution impregnation on the surface properties of lignite semi-coke and its mercury removal performance at elevated temperature. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(3): 702-708.
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