第35卷第4期高校化学工程学报No.4Vol.352021年8月JournalofChemicalEngineeringofChineseUniversitiesAug.2021文章编号：1003-9015(2021)04-0753-08高岭土负载氧化铜脱除还原态砷的机制研究汪宁波,仲兆平,杜浩然(东南大学能源热转换及其过程测控教育部重点实验室,江苏南京210096)摘要：为了研究高岭土负载氧化铜后对还原态砷的吸附机理，利用密度泛函理论(DFT)分别计算高岭土及高岭土负载氧化铜后对3种还原气氛下典型砷组分的吸附构型，通过比较分析，获得3种砷的化合物(As2,As4,AsH3)与高岭土-氧化铜形成的稳定构型，同时分析各构型的吸附能、Mulliken电荷转移、偏态密度(PDOS)及差分电荷密度。结果表明，高岭土负载氧化铜(CuO/kaolinite)对3种分子的吸附能明显降低，体现较强的化学吸附作用，As4的吸附效果最好；氧化铜在吸附过程中作为主要活性分子得到大部分转移的电子；在3种稳定的构型中出现强度较高的共价键与氢键。关键词：吸附剂；密度泛函理论；砷；吸附作用中图分类号：X511文献标志码：ADOI：10.3969/j.issn.1003-9015.2021.04.022MechanismofreducedarsenicremovalbykaolinitesupportedcopperoxideWANGNing-bo,ZHONGZhao-ping,DUHao-ran(KeyLaboratoryofEnergyThermalConversionandControloftheMinistryofEducation,SoutheastUniversity,Nanjing210096,China)Abstract:Inordertostudytheadsorptionmechanismofreducedarsenicbycopperoxideloadedkaolinite,densityfunctionaltheory(DFT)wasusedtocalculatetheadsorptionconfigurationsofthreetypicalarseniccomponentsunderreducingatmospherebykaoliniteandcopperoxideloadedkaolinite.Thestableconfigurationsofthreearseniccompounds(As2,As4,AsH3)onkaolinite(001)surfacewithcopperoxide(CuO/kaolinite)wereobtainedthroughcomparativeanalysis,andtheadsorptionenergy,Mullikenchargetransfer,densityofstatesandelectrondensitydifferenceofeachconfigurationwereanalyzed.Theresultsshowthattheadsorptionenergyofthethreemoleculesonkaolinitewithcopperoxideissignificantlyreduced,whichindicatesstrongchemicaladsorptioneffects.As4showedthebestadsorptioneffect.Copperoxideplayedamajorroleintheadsorptionprocess,whichgotmostofthetransferredelectrons.Strongercovalentbondsandhydrogenbondsappearedinthethreestableconfigurations.Keywords:adsorbents;densit...
