摘要
为了寻求修复地下水中氯酚污染物的高效吸附剂,采用十六烷基三甲基溴化铵(HDTMA)对凹凸棒土进行有机改性,考察了有机改性凹土对地下水中2,4-二氯苯酚(DCP)的吸附性能.实验结果表明,有机改性能显著提高凹凸棒土对DCP的吸附效果.当DCP浓度为20 mg/L、吸附剂投量为1.2 g/L时,有机改性凹土对DCP的去除率达到91.5%,而凹凸棒原土则仅为27.8%.有机改性凹土吸附DCP的最佳投量为1.2 g/L,最佳吸附时间为30 min.Langmuir模型和Freundlich模型均能较好地拟合DCP的等温吸附线,且前者的拟合结果更好.DCP在有机改性凹土上的饱和吸附量可达107.53 mg/g,而在凹凸棒土原土上仅为39.06 mg/g.此外,重金属离子的存在会降低有机改性凹土对DCP的吸附能力.Pb2+存在时DCP在有机改性凹土上的饱和吸附容量为45.70 mg/g,Cd2+存在时则为31.20 mg/g,分别为无重金属离子存在时的42.4%和29.0%.
To seek an efficient adsorbents of chlorophenol remediation in groundwater,the adsorbent hexadecyltrimethylammonium（HDTMA） attapulgite was obtained by modifying attapulgite with HDTMA,and its adsorption behaviors for 2,4-dichlorophenol（DCP） in groundwater samples were investigated.The experimental results show that the adsorption of DCP on HDTMA-attapulgite can be significantly enhanced by organic modification.When the concentration of DCP is 20 mg/L and the dosage of the adsorbent is 1.2 g/L,the removal efficiency of DCP by HDTMA-attapulgite is 91.5% while it is only 27.8% by original attapulgite.The optimal dosage of HDTMA-attapulgite is 1.2 g/L and the optimal adsorption time is 30 min.The adsorption isotherms can be well described by the Langmuir and Freundlich models,and the former fits better with the experimental data.The adsorption capacities of DCP on HDTMA-attapulgite and original attapulgite are 107.53 and 39.06 mg/g,respectively.In addition,the adsorption capacity of DCP on HDTMA-attapulgite is reduced in the existence of heavy metal ions.In the presence of Pb2＋ and Cd2＋,DCP adsorption capacities on HDTMA-attapulgite are 45.70 and 31.20 mg/g,respectively,which are only 42.4% and 29.0% of the capacities in the absence of corresponding heavy metal ions.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2012年第6期1217-1220,共4页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(50909019
51079029)
江苏省自然科学基金资助项目(BK2009294)
关键词
有机改性凹土
地下水
2
4-二氯酚
重金属
等温吸附线
surfactant-modified attapulgite
groundwater
2
4-dichlorophenol
heavy metals
adsorption isotherm
