三种ZnAl-稀有金属LDHs除磷效果对比试验与机理分析  

Comparative Experimental Study and Mechanism Analysis on Phosphorus Removal with Three Types of Zn-Al-rare Metal LDHs

作　　者：吴梦豪 姜应和[1,2] 李大琳 WU Meng-hao;JIANG Ying-he;LI Da-lin(School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China;Department of Urban Construction Engineering,Wenhua College,Wuhan 430074,China)

机构地区：[1]武汉理工大学土木工程与建筑学院,武汉430070 [2]文华学院城市建设工程学部,武汉430074

出　　处：《武汉理工大学学报》2024年第7期98-106,共9页Journal of Wuhan University of Technology

基　　金：路德环境科技股份有限公司科技攻关项目(LDHJ20200102)。

摘　　要：采用共沉淀法制备了高价金属配比为M∶Al=1∶20^(M为La、Zr或Ce~)的三种Zn A-l稀有金属三元LDHs,表征了它们的晶体结构、微观形貌和元素组成。通过吸附除磷试验,评估了它们的除磷性能,并深入探讨了除磷机制及吸附性能差异的原因。结果表明:三种Zn A-l稀有金属LDHs均成功合成;它们对磷酸盐的吸附量的大小关系为:La-LDHs>Zr-LDHs>Ce-LDHs;它们对磷酸盐的吸附以化学吸附为主,涉及静电相互作用、阴离子-金属配位体、层间阴离子交换,且吸附能力受CO_(3)^(2-)的影响大;_(La-LDHs)展现出比其他两种LDHs更好的除磷性能,主要原因是镧离子较大的离子半径、舒展的d轨道和吸附剂粗糙的外表面。Three types of ZnAl-rare metal ternary LDHs with M:Al=1:20(M=La,Zr,or Ce) were synthesized by co-precipitation,and their crystal structure,micro-morphology,and elemental composition were characterized.The adsorption experiments were carried out to compare their performance in phosphate removal.The mechanisms of phosphate removal and the reasons for the differences in their adsorption capacities were analysed in depth.The results indicated that(a) all three LDHs were successfully synthesized;(b) their phosphate adsorption capacities were in the order of La-LDHs>Zr-LDHs>Ce-LDHs;(c) the phosphate adsorption was primarily chemical,involving electrostatic interactions,anion-metal coordination,and interlayer anion exchange,and their adsorption capacities were significantly inhibited by CO_3~(2-);(d)the superior phosphate removal performance of La-LDHs compared to the other two types of LDHs was mainly attributed to the larger ionic radius,more extended d orbitals of lanthanum ions and the rougher adsorbent surface.

关 键 词：三元LDHs 稀有金属 磷酸盐 吸附 比较 

分 类 号：X52[环境科学与工程—环境工程] X703