废CeO_(x)-MnO_(x)基SCR脱硝催化剂还原酸浸综合回收铈锰  

Comprehensive recovery of cerium and manganese from waste CeO_(x)-MnO_(x)-based SCR denitrification catalysts by reductive acid leaching

作　　者：余正伟 张晓霞 雷杰 李澳 王光应 丁祥[1] 龙红明[1,2] YU Zhengwei;ZHANG Xiaoxia;LEI Jie;LI Ao;WANG Guangying;DING Xiang;LONG Hongming(Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology),Ministry of Education,Maanshan 243002,Anhui,China;School of Metallurgical Engineering,Anhui University of Technology,Maanshan 243002,Anhui,China;Energy Saving and Pollution Control in Metallurgical Process Engineering Technology Research Center of Education Department of Anhui Province,Maanshan 243002,Anhui,China;Anhui Yuanchen Environmental Protection Technology Company Limited,Hefei 230012,Anhui,China)

机构地区：[1]冶金减排与资源综合利用教育部重点实验室(安徽工业大学),安徽马鞍山243002 [2]安徽工业大学冶金工程学院,安徽马鞍山243002 [3]冶金过程节能与污染控制安徽省教育厅工程技术研究中心,安徽马鞍山243002 [4]安徽元琛环保科技股份有限公司,安徽合肥230012

出　　处：《化工进展》2022年第9期5122-5131,共10页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(51704009,52174290);冶金减排与资源综合利用教育部重点实验室开放基金(JKF21-07);冶金过程节能与污染控制安徽省教育厅工程技术研究中心开放基金(GKF20-2)。

摘　　要：废选择性催化还原(SCR)脱硝催化剂中含有大量的有价金属,直接废弃易造成资源浪费及环境污染。以废CeO_(x)-MnO_(x)基SCR脱硝催化剂为原料,采用热力学分析结合湿法冶金实验方法,研究了浸出条件对Ce、Mn元素浸出率的影响。结果表明,废催化剂直接酸浸Ce、Mn元素浸出率低,还原-酸浸Ce、Mn元素热力学条件上可行,抗坏血酸对Ce、Mn高价氧化物有明显的还原作用。当抗坏血酸质量分数为30%、硫酸浓度2mol/L、液固比6∶1、搅拌速度350r/min、80℃恒温反应5h时,Ce、Mn的浸出率分别达到92.09%、95.51%。加入抗坏血酸后,部分Ce^(4+)和Mn^(4+)还原为Ce^(3+)和Mn^(2+),Ce^(4+)/Ce的比值由75.82%降低到71.62%,Mn^(4+)/Mn的比值由29.39%降低到27.17%,同时削弱了高价Ce辅助低价Mn向高价Mn转化的作用,使得Ce、Mn高效浸出,为CeO_(x)-MnO_(x)基废催化剂中Ce、Mn资源化利用奠定了基础。Waste selective catalytic reduction(SCR)denitrification catalyst contains amounts of valuable metals,which directly landfill will cause resources waste and environmental pollution.The effects of leaching conditions on selective acid leaching of Ce and Mn elements from waste CeO_(x)-MnO_(x) SCR denitrification catalyst were investigated by thermodynamic analysis and hydrometallurgy experimental study.The results confirmed that the direct-acid leaching rates of Ce and Mn from waste CeO_(x)-MnO_(x) SCR catalyst were very low,the reduction-acid leaching of Ce and Mn was feasible under thermodynamic conditions,and the ascorbic acid had obvious reduction effect on Ce and Mn high-valence oxides.When the experimental conditions were as follows:ascorbic acid mass ratio of 30%,sulfuric acid concentration of 2mol/L,liquid-solid ratio of 6∶1,stirring speed of 350r/min and constant temperature of 80℃with reaction time of 5h,the leaching rates of Ce and Mn reached 92.09%and 95.51%,respectively,and the mass ratios of Ce^(4+)/Ce and Mn^(4+)/Mn decreased from 75.82%to 71.62%and 29.39%to 27.17%,respectively.It was indicated that the addition of the ascorbic acid reduced part of Ce^(4+)(Mn^(4+))to Ce^(3+)(Mn^(2+))and weakened the positive effect of high valence Ce on the transition of Mn from the low-valence,thus improving the leaching rates of Ce and Mn,which had laid the groundwork for resource utilization of Ce and Mn in waste CeO_(x)-MnO_(x)-based SCR denitrification catalysts.

关 键 词：选择催化还原 废催化剂 酸浸 还原 回收 资源化利用 

分 类 号：TF11.31[冶金工程—冶金物理化学]