Adsorption performance of semi-coke modified by KMnO4 solution for gas-phase Hg0 in flue gas
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摘要: 在小型固定床实验台上利用半焦及其KMnO4溶液改性样品进行气态Hg0吸附实验。结果表明,在低温时原料半焦对气态Hg0具有良好的吸附性能,升温则使其吸附性能迅速降低;经高锰酸钾溶液浸渍处理后,改性半焦在高温140 ℃时吸附性能明显提高,对浸渍样品在250 ℃进行热处理可使其吸附性能进一步提高。BET结果表明,原料半焦具有较发达的微孔结构,改性处理使微孔比例下降,孔隙结构发达程度降低;XPS测试表明,改性半焦表面的汞主要以氧化态(Hg2+)形式存在,高价锰化合物(KMnO4、K2MnO4、MnO2)是主要的氧化活性物质。Abstract: In an attempt to develop a novel and more effective sorbent with low-cost for the removal of gas-phase Hg0 from flue gas, the adsorption performance of semi-coke and KMnO4 solution-modified semi-coke for gas-phase Hg0 was investigated with a bench-scale fixed-bed reactor system. The experimental results suggest that the adsorption performance of semi-coke is good at low temperature but weak at higher temperature. The semi-cokes impregnated by KMnO4 solution have excellent adsorption performance for gas-phase Hg0 at 140 ℃, and can be further enhanced by heating the impregnated samples at 250 ℃. The BET analysis shows that the semi-coke has rich micro-pores but become poor after modification. The XPS results indicates that the adsorbed mercury on the surface of the modified semi-coke samples mainly exists in oxidation state (Hg2+) and these compounds (KMnO4, K2MnO4 and MnO2 ) play a key role in the oxidation reaction of gas-phase Hg0.
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LI P, FENG X B, QIU G L, SHANG L H, LI Z G. Mercury pollution in Asia: A review of the contaminated sites[J]. J Hazard Mater, 2009, 168(2/3):591-601. GLODEK A, PACYNA J M. Mercury emission from coal-fired power plants in Poland[J]. Atmos Environ,2009, 43(35): 5668-5673. 杨士建. 磁性铁基尖晶石对气态零价汞的化学吸附研究. 上海: 上海交通大学, 2012. (YANG Shi-jian. Chemical adsorption of gaseous elemental mercury on magnetic Fe based spinel. Shanghai:Shanghai Jiaotong University, 2012.) 李建荣, 何炽, 商雪松, 陈进生, 喻小伟, 姚沅君. SCR 脱硝催化剂对烟气中零价汞的氧化效率研究[J]. 燃料化学学报, 2012, 40(2): 241-246. (LI Jian-rong, HE Chi, SHANG Xue-song, CHEN Jin-sheng, YU Xiao-wei, YAO Yuan-jun. Oxidation efficiency of elemental mercury in flue gas by SCR De-NOx catalysts[J]. Journal of Fuel Chemistry and Technology, 2012, 40(2): 241-246. 徐梅玫, 许飘, 李彩亭, 高招, 樊小鹏. 稻壳活性炭对单质汞吸附性能的实验研究[J]. 环境工程学报, 2010, 4(9): 2065-2068. (XU Mei-mei, XU Piao, LI Cai-ting, GAO Zhao, FAN Xiao-peng. An experimental study on adsorptive performance of rice husk activated carbon to mercury[J]. Chinese Journal of Environmental Engineering,2010, 4(9): 2065-2068.) 张 郃, 赵建涛, 房倚天, 王洋. 活性炭催化氧化脱除单质汞的研究[J]. 燃料化学学报, 2011, 39(5): 373-377. (ZHANG He, ZHAO Jian-tao, FANG Yi-tian,WANG Yang. Stabilized oxidation and adsorption of elemental mercury by activated carbon[J]. Journal of Fuel Chemistry and Technology, 2011, 39(5):373-377.) 于英民, 郭瑞莉, 李春虎. 半焦吸附剂烟气脱硫脱硝性能[J]. 燃料化学学报, 2011, 39(5): 385-389. (YU Ying- min, GUO Rui-li, LI Chun-hu. Flue gas desulfurization and denitrification performance of the semi-coke adsorbents[J]. Journal of Fuel Chemistry and Technology, 2011, 39(5): 385-389.) WANG W, LI C, YAN Z. Study on molding semi-coke used for ue-gas desulphurization[J]. Catal Today,2010, 158(3/4): 235-240. 赵振国. 吸附作用应用原理[M]. 北京: 化学工业出版社, 2005: 63-64. (ZHAO Zhen-guo. Application and principle of adsorption[M]. Beijing:Chemical Industry Press, 2005: 63-64. ) 叶群峰, 王成云, 徐新华, 汪大翚. 高锰酸钾吸收气态汞的传质-反应研究[J]. 浙江大学学报(工学版), 2007, 41(5): 831-835. (YE Qun-feng, WANG Cheng-yun, XU Xin-hua, WANG Da-hui. Mass transfer-reaction of Hg0 absorption in potassium permanganate[J]. Journal of Zhejiang University (Engineering Science)2007, 41(5): 831-835.) YANG S, GUO Y, YAN N, QU Z, XIE J, YANG C, JIA J. Capture of gaseous elemental mercury from ue gas using a magnetic and sulfur poisoning resistant sorbent Mn/γ-Fe2O3 at lower temperatures[J]. J Hazard Mater, 2011, 186(1): 508-515. 上官炬, 李转丽, 杨直, 樊惠玲, 沈芳, 苗茂谦. 高温热处理对活性半焦烟气脱硫的影响[J]. 太原理工大学学报, 2005, 36 (2): 134-136. (SHANG Guan-ju, LI Zhuan-li, YANG Zhi, FAN Hui-ling, SHEN Fang, MIAO Mao-qian. The Effect of heating semi-coke at high temperature on its SO2 removal capacity[J]. Journal of Taiyuan University of Technology, 2005, 36(2): 134-136.) DI CASTRO V, CIAMPI S. XPS study of the growth and reactivity of Fe/MnO thin films[J]. Surf Sci,1995, 331~333(Part A): 294-299. OKU M. X-ray photoelectron spectra of KMnO4 and K2MnO4 fractured in situ[J]. J Electron Spectrosc Relat Phenom, 1995, 74(2): 135-148. NESBITT H W, BANERJEE D. Interpretation of XPS Mn (2p) spectra of Mn oxyhydroxides and constraints on the mechanism of MnO2 precipitation[J]. Am Mineral, 1998, 83(3/4):305-315. JIN X B, ZHOU W Z, ZHANG S W, CHEN G Z. Nanoscale microelectrochemical cells on carbon nanotubes[J]. Small, 2007, 3(9): 1513-1517. WILCOX J, SASMAZ E,KIRCHOFER A, LEE S-S. Heterogeneous mercury reaction chemistry on activated carbon[J]. J Air Waste Manage Assoc, 2011, 61(4): 418-426. HUTSON N D, ATTWOOD B C, SCHECKEL K G. XAS and XPS characterization of mercury binding on brominated activated carbon[J]. Environ Sci Technol, 2007, 41(5): 1747-1752.
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