花生壳-耐性菌株复合吸附剂对Pb^(2+)的动态吸附特性  

Dynamic adsorption of Pb^(2+) in aqueous solutions ontoa composite adsorbent consisting ofpeanut shell andaspergillus oryzae

作　　者：冀泽华 吴晓芙[1] 冯冲凌[1] 李刘刚 周桑扬 刘相君[1] JI Ze-hua;WU Xiao-fu;FENG Chong-ling;LI Liu-gang;ZHOU Sang-yang;LIU Xiang-jun(Institute of Environmental Engineering Research, Central South University of Forestry and Technology, Changsha 410004, China)

机构地区：[1]中南林业科技大学环境科学与工程研究所,湖南长沙410004

出　　处：《中国环境科学》2016年第11期3368-3375,共8页China Environmental Science

基　　金：国家"十二五"科技惠民计划项目(2012GS430203);国家"十二五"科技支撑计划项目(2012BAC09B03);湖南省环境科学与工程重点学科建设项目资助;中南林业科技大学研究生科技创新基金资助项目(CX2015B29);湖南省研究生科研创新项目(CX2015B306)

摘　　要：为了提高生物质吸附重金属离子的能力,以花生壳(PS)与耐铅米曲霉菌(HA)为原料制备了复合吸附剂(PSH),通过静态与动态吸附试验考察了PSH在不同操作条件下对Pb^(2+)的动态吸附特性.结果表明,PSH较PS的动、静态吸附能力均明显提升,PSH的动态吸附穿透时间随柱高增加或流速、初始浓度的减小而增加,传质区长度随柱高减小或流速、初始浓度的增加而增加,流速变化对穿透时间和传质区长度影响最大.Thomas模型较好的描述了PSH对Pb^(2+)的动态吸附过程(R^2>0.95),说明该过程中内部扩散和外部扩散并非限速步骤.BDST模型准确预测了PSH吸附柱高度与不同时间点浓度c_t与起始浓度c_0的之比、不同流速和初始浓度下穿透时间的关系,当c_t/c_0=0.6时,预测与实测值相对误差平均值仅为2.89%.In order to improve the ability of peanut shell powders (PS) used as bio-adsorbent to remove heavy metal ions,an isolated Pb2+-resistant strain, Aspergillus oryzae (HA), was mixed with peanut shell powders to form a compositeadsorbent (PSH). Static and dynamic adsorption experiments were carried out todetermine the adsorption capacity of Pb2+ions onto both PS and PSH in aqueous solutions.The effects of the fixed adsorption bed height, flow rates and initial Pb2+ionconcentration on adsorption behaviors of PSH were investigated. The results from the study indicated that theadsorption capacity of PSH was significantly higher than that of PS. Both the breakthrough time and the height of masstransfer zone increased with increase inbed height and decrease inflow rate and initial concentration. In comparison, theeffect of flow rates was significant at higher levels than that of bed height and initial concentration.Thomas model gavesatisfactory descriptions on column Pb2+ adsorption kinetics (R2>0.95), indicating that neither external nor internaldiffusions were the factors limiting the steps ofcolumn adsorption. BDST model could accurately predict the relationshipamong bed height, ct/c0 (the ratio of concentration at a given time ct to initial concentration c0) and breakthrough timeunder different operation conditions. The average deviation error were 2.89 % at ct/c0=0.6.

关 键 词：花生壳 米曲霉 吸附 铅离子 吸附柱 穿透曲线 

分 类 号：X703.5[环境科学与工程—环境工程]