摘要
通过静态吸附实验,研究了酸碱度（pH）、两种重金属离子（Pb2＋、Cd2＋）单独及共同作用对棕壤吸附五氯酚（PCP）的影响。结果表明,棕壤对PCP的吸附量随溶液pH的升高而降低,且随Pb2＋和Cd2＋浓度的升高,吸附呈先下降后升高的趋势,Freundlich模型能较好的描述棕壤对PCP的吸附行为,吸附呈非线性。pH=4.0～5.9范围时,Pb2＋促进棕壤对PCP的吸附,pH=5.9～10.0范围时,Pb2＋抑制其吸附;pH=4.0～8.8范围时,Cd2＋抑制棕壤对PCP的吸附,pH=8.8～10.0范围时,Cd2＋促进其吸附。傅里叶变换红外光谱及紫外-可见光谱分析进一步表明,溶液中PCP与金属离子形成了复合离子（PCP-Me＋）,PCP-Me＋的稳定常数以及金属离子和PCP的形态变化明显影响棕壤吸附PCP,离子强度的变化对PCP的吸附也有一定的影响。
Effect of pH, two heavy metal ion （Pb2＋and Cd2＋） and the co-influences on the adsorption of pentachlorophenol （PCP） by brown soil were studied using static adsorption experiments. The adsorption capacity of PCP by brown soil decreased with the solution pH increased. Adsorption of PCP by brown soil decreased firstly and increased thereafter with the increment of Pb2＋ and Cd2＋ concentrations. The results indicated that the adsorption isotherm of PCP by brown soil followed Freundlich model, and the sorption process was nonlinear. Pb2＋ enhanced the adsorption of PCP by brown soil at pH 4.0 to 5.9, and impeded at pH 5.9 to 10.0. The presence of Cd2＋ impeded the PCP sorption by brown soil at pH 4.0 to 8. 8, and enhanced at pH 8. 8 to 10.0. The formed ion pairs of pentachlorophenolate- metal （PCP-Me＋ ） in the solution were illustrated by UV-Visible and FTIR spectra. The stability constants of PCP-Me＋ , speciation of metal ion and PCP obviously affected the PCP adsorption. In addition, Ionic strength also played an important role for the adsorption of PCP by brown soil.
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第11期89-94,117,共7页
Periodical of Ocean University of China
基金
国家水体污染控制与治理科技重大专项(2013ZX07202-007)
教育部优秀新世纪人才支持计划项目(NCET-10-0758)资助
