摘要
为增加脱硝催化剂的酸性位点和比表面积,以稀土尾矿为活性主体,通过物理球磨方式添加γ-Al2O3,制得NH3-SCR催化剂,脱硝温度为100~400℃.结果表明:原尾矿脱硝活性为7.6%,γ-Al2O3的脱硝活性为9.4%,稀土尾矿添加50%γ-Al2O3脱硝活性达到了64.8%,即添50%γ-Al2O3后加极大程度地提高了尾矿的脱硝活性.XRD实验结果表明:Al2O3不会与尾矿成分发生反应生成新的物质.SEM实验结果表明:当添加γ-Al2O3低于50%时,γ-Al2O3均匀分散在尾矿表面,当添加65%γ-Al2O3和80%γ-Al2O3时,γ-Al2O3发生团聚,分散性较差.NH3-TPD实验结果表明:添加γ-Al2O3为脱硝催化剂增加酸性位点,但是当添加γ-Al2O3过低时(15%、35%),吸附NH3量不足,催化反应进行不完全.BET实验结果表面:添加γ-Al2O3可以增加尾矿的比表面积.
In order to increase the acidic sites and specific surface area of the denitration catalyst,with rare earth tailings as the active main body,γ-Al2O3 was added by physical ball milling to prepare NH3-SCR catalyst.The denitration temperature was 100~400℃.The experimental results showed that the denitration activity of the original tailings was 7.6%,the denitration activity ofγ-Al2O3 was 9.4%,and the denitration activity of rare earth tailings with 50%γ-Al2O3 reached 64.8%,That was to say,adding 50 wt%γ-Al2O3 could denitrification activity of tailings greatly.The XRD results showed thatγ-Al2O3 cann’t react with tailings to form new materials.The SEM results showed thatγ-Al2O3 was uniformly dispersed on the tailings when adding weight ofγ-Al2O3 was less than 50%.If adding weight ofγ-Al2O3 was more than 50%,γ-Al2O3 agglomerated on the tailings and showed poor dispersion.The results of NH3-TPD showed that addingγ-Al2O3 can enhance the amount of acid sites.And the NH3 adsorption first increased and then decresed with the increase of addition weight ofγ-Al2O3.However,if addition weight ofγ-Al2O3 was too low(15 wt%,35 wt%),the amount of NH3 adsorption was inadequate,resulting in incomplete catalytic reaction.The BET results showed that the specific surface area of tailings could be increased by addingγ-Al2O3.
作者
付金艳
王振峰
白心蕊
崔梦壳
武文斐
FU Jin-yan;WANG Zhen-feng;BAI Xin-rui;CUI Meng-ke;WU Wen-fei(School of Energy and Environment,Inner Mongolia University of Science and Technology,Baotou 014010,China;State Key Laboratory of Comprehensive Utilization of Polymetallic Resources in Baiyun Obo Mine,Inner Mongolia Autonomous Region,Baotou 014010,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2020年第9期3741-3747,共7页
China Environmental Science
基金
国家自然科学基金资助项目(51866013)
内蒙古自治区自然科学基金资助项目(2019ZD13,2017MS(LH))
内蒙古自治区重大基础研究开放课题资助(0406091701)。
关键词
稀土尾矿
拟薄水铝石
酸性位点
催化脱硝
rare earth tailings
pseudo boehmite
acid sites
catalytic denitratio
