SiO_(2)改性Ce-V-W/Ti催化剂载体的抗碱(土)金属中毒性能  

Resistance of SiO_(2)modified Ce-V-W/Ti catalyst support to alkali(earth)metal poisoning

作　　者：庄柯 陈宏 许芸 仲兆平 周峻伍 周凯 董月红 ZHUANG Ke;CHEN Hong;XU Yun;ZHONG Zhaoping;ZHOU Junwu;ZHOU Kai;DONG Yuehong(National Key Laboratory of Low Carbon Intelligent Coal-fired Power Generation and Ultra Clean Emissions,National Energy Group Science and Technology Research Institute Company Limited,Nanjing 210023,Jiangsu,China;Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 211189,Jiangsu,China)

机构地区：[1]国家能源集团科学技术研究院有限公司低碳智能燃煤发电与超净排放全国重点实验室,江苏南京210023 [2]东南大学能源与环境学院能源热转换及其过程测控教育部重点实验室,江苏南京211189

出　　处：《化工进展》2025年第1期266-276,共11页Chemical Industry and Engineering Progress

基　　金：低碳智能燃煤发电与超净排放全国重点实验室开放课题(D2022FK076);江苏省科技成果转化专项资金项目(BA2022073)。

摘　　要：为了提升Ce-V-W/Ti催化剂耐碱(土)金属中毒性能,本文使用溶胶-凝胶法制备了TiO_(2)载体并进行了SiO_(2)掺杂改性,通过浸渍法制备了Ce-V-W/Ti-Si催化剂。采用浸渍法模拟了CaCO_(3)、K_(2)O等碱物种中毒,探究了SiO_(2)改性载体对催化剂的脱硝活性和抵御碱(土)金属中毒性能的影响,并使用X射线光电子能谱、N_(2)吸附-脱附、H2-程序升温还原、NH_(3)-程序升温脱附等表征手段对催化剂进行了表征分析。实验结果表明,对Ce-V-W/Ti催化剂载体进行SiO_(2)改性会降低其中低温段的脱硝活性,但能明显提升催化剂对碱物种的耐受性,总体上,Ce1V1W7/Ti-Si4对碱物种的耐受性最好,各类碱物种对其脱硝活性的毒害程度为K_(2)O>Na_(2)O>CaCO_(3)>CaO>CaSO_(4)。表征结果显示,SiO_(2)改性削弱了催化剂表面Ce氧化物活性,但显著增加了催化剂的比表面积和酸性位点数量,并在催化剂碱中毒时保护了活性金属氧化物的还原性。In order to improve the resistance of Ce-V-W/Ti catalysts to alkali(earth)metal poisoning,TiO2 supports were prepared by sol-gel method and then modified by SiO_(2)doping,and Ce-V-W/Ti-Si catalysts were prepared by impregnation method.The impregnation method was employed to simulate the poisoning effect on alkali species such as CaCO_(3)and K_(2)O.The influence of SiO_(2)-modified support on the denitration activity and resistance against alkali metal poisoning of the catalyst was investigated.Characterization techniques including X-ray photoelectron spectroscopy,N_(2)adsorption-desorption,H2-temperature programmed reduction,and NH3-temperature programmed desorption were employed to analyze the catalysts.Experimental results indicated that the SiO_(2)modification of the Ce-V-W/Ti catalyst support reduced its denitration activity at low temperatures but significantly enhanced the catalyst’s tolerance against alkali species.Overall,Ce1V1W7/Ti-Si4 exhibited the best resistance against alkali species,with the poisoning severity of various alkali species ranked as K_(2)O>Na_(2)O>CaCO_(3)>CaO>CaSO_(4).The characterization results showed that SiO_(2)modification weakened the activity of Ce oxide on the surface of the catalyst,but significantly increased the specific surface area and the number of acidic sites of the catalyst,and protected the reducibility of the active metal oxide during alkalosis.

关 键 词：选择催化还原 催化剂载体 活性 SiO_(2)改性 碱中毒 

分 类 号：TQ426[化学工程] X511[环境科学与工程—环境工程]