牛粪源蚓粪及其生物炭对Pb^2＋、Cd^2＋的吸附特性  

Adsorption of Pb^(2+) and Cd^(2+) from Aqueous Solution Using Vermicompost Derived from Cow Manure and Its Biochar

作　　者：杜文慧[1] 朱维琴[1] 潘晓慧[1] 沈旭阳 陈思远[1] 陈可乐[1] 坎吉汗·木沙拉 张杭君[1] 丁颖[1] 

机构地区：[1]杭州师范大学生命与环境科学学院,杭州市生态系统保护与恢复重点实验室,杭州310036

出　　处：《环境科学》2017年第5期2172-2181,共10页Environmental Science

基　　金：浙江省自然科学基金项目(LY17B070004);国家自然科学基金项目(B21207029);杭州师范大学本科生创新能力提升工程项目(CX2016105);杭州师范大学实验室开放项目(SYSKF201609)

摘　　要：以牛粪源蚓粪(CV)为原料,于350℃下热解制备蚓粪生物炭(标记为CVC350)并表征其物理化学性质,进一步就CV和CVC350对Pb^(2+)和Cd^(2+)的吸附性能进行了研究,结果表明:与CV相比,CVC350的比表面积增大,孔径变小,芳香性和非极性增强.CV和CVC350对Pb^(2+)和Cd^(2+)的等温吸附曲线均符合Langmuir方程,两者对Pb^(2+)的最大吸附量表现为CVC350>CV,而两者对Cd^(2+)的最大吸附量间差异不明显.解吸特性研究表明,CV和CVC350对Pb^(2+)的吸附率明显高于其对Cd^(2+)的吸附率,且两者的吸附态Cd^(2+)与其吸附态Pb^(2+)相比均相对更易解吸.CV和CVC350对Pb^(2+)的吸附动力学均为快速吸附过程,而CV和CVC350对Cd^(2+)的吸附动力学则均表现为快速吸附和慢速吸附两个阶段.当溶液初始pH较低时,CV和CVC350对Pb^(2+)和Cd^(2+)吸附量受pH影响明显,且CV和CVC350对Cd^(2+)的吸附受pH变化的影响相对更大.FTIR分析表明,CV对Pb^(2+)和Cd^(2+)的吸附位点主要集中在脂肪醇或脂肪酸、碳酸盐和磷酸盐,而CVC350对Pb^(2+)和Cd^(2+)的吸附位点主要为芳香醇或芳香酸和碳酸盐.Using vermicompost （CV） as raw material, its biochar （CVC350） was prepared at 350℃ and then their physio-biochemical properties were characterized. Furthermore, adsorption studies were performed in a batch system for removing Pb^2＋ and Cd^2＋ ions from solution. The characterization results revealed much higher surface area, smaller pore size, greater aromaticity and nonpolarity of CVC350 as compared to CV. Batch adsorption experiments revealed that both the adsorption of Pb^2＋ and Cd^2＋ onto CV or CVC350 fitted Langmuir isotherm model very well, and the maximum adsorption capacity of Pb^2＋ was in the order of CVC350〉CV, but no difference was observed for the adsorption capacity of Cd^2＋ between CV and CVC350. The desorption studies showed that both CV and CVC350 had much higher adsorption rate for Pb^2＋ than that for Cd^2＋, and the Cd^2＋ adsorbed could be more easily desorbed from CV and CVC350 compared with that for the Pb^2＋ adsorbed. Both the dynamic adsorption process of Pb^2＋ onto CV and CVC350 was a rapid process, however, the adsorption process of Cd^2＋ onto CV and CVC350 could be separated into the first rapid step and the second slower step. The adsorption capacity of Pb^2＋ or Cd^2＋ onto CV and CVC350 was only affected by the much lower initial pH of the solution, besides, the adsorption capacity of Cd^2＋ onto CV and CVC350 was relatively more influenced by the initial pH compared with that of Pb^2＋. Moreover, FTIR analysis showed that the adsorption of Pb^2＋ and Cd^2＋on CV depended on the active sites such as aliphatic alcohol, aliphatic acid,carbonates as well as phosphate while that on CVC350 mainly relied on aromatic alcohol, aromatic acid and carbonates.

关 键 词：蚓粪 生物炭 吸附 PB2+ Cd2+ 

分 类 号：X705[环境科学与工程—环境工程]