核桃青皮生物炭对重金属铅、铜的吸附特性研究  

Adsorption of lead and copper from aqueous solutions on biochar produced from walnut green husk

作　　者：谢超然[1] 王兆炜[1] 朱俊民[1] 高俊红[1] 张涵瑜[1] 谢晓芸[1] 金诚[1] 

机构地区：[1]兰州大学资源环境学院甘肃省环境污染预警与控制重点实验室,兰州730000

出　　处：《环境科学学报》2016年第4期1190-1198,共9页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.21307050);兰州大学中央高校基本科研业务费专项资金(No.lzujbky-2014-129;lzujbky-2015-214)~~

摘　　要：采用500℃限氧裂解法将农林废弃物核桃青皮制成核桃青皮生物炭,进行了核桃青皮生物炭对铅、铜的批量吸附实验.同时,利用扫描电镜、FTIR红外等方法探讨了核桃青皮炭吸附Pb^(2+)、Cu^(2+)的特性,探究了吸附时间、溶液初始浓度、吸附温度、吸附剂投加量、溶液初始pH等因素对核桃青皮生物炭吸附Pb^(2+)、Cu^(2+)作用的影响,讨论了吸附动力学特性及吸附等温特性.结果表明:温度298.15 K、pH为3~6条件下,核桃青皮生物炭吸附Pb^(2+)和Cu^(2+)在20 min内即可达到吸附平衡,核桃青皮炭最佳投加量分别为0.8、1.5 g·L^(-1),最大吸附量分别为476.190、153.846 mg·g^(-1);吸附过程符合准二级动力学方程,等温吸附曲线符合Langmuir方程,说明其吸附过程主要是近似单分子层的化学吸附.In this study,the adsorptions of Pb（2＋）and Cu（2＋）in aqueous solutions by biochar derived from walnut green husk at pyrolysis temperature of 500℃ were evaluated. The characteristics of adsorbent before and after adsorption were mainly observed by Scanning Electron Microscope and FTIR spectra.The effects of contact time,initial Pb（2＋）and Cu（2＋）concentration,temperature of experiment,adsorbent dose and initial p H in batch sorption experiments were investigated. The sorption capability was evaluated by adsorption kinetics and isotherm models. The maximum Pb（2＋）and Cu（2＋）adsorption capacity of walnut green husk biochar reached 476. 190 and 153. 846 mg·g（-1）,respectively. The optimum adsorption conditions were found to occur at reaction time of 20 min,0. 8（ Pb（2＋））,1. 5（ Cu（2＋）） g·L（-1） adsorbent dose and initial pH 3 6. Furthermore,the adsorption kinetics was best fitted by the pseudosecond order model,while the adsorption equilibrium was best described by linear and Langmuir isotherms. This indicated that Pb（2＋）and Cu（2＋）ions were adsorbed onto the walnut green husk biochar by chemical interactions via monolayer.

关 键 词：生物炭 核桃青皮 吸附 铅 铜 

分 类 号：X703[环境科学与工程—环境工程]