【摘要】 两性表面修饰可以同时提高黏土矿物对有机物、重金属的吸附性能,研究两性修饰土对多种重金属共存条件下的吸附及交互作用对于其应用具有实际意义.采用红外光谱（FTIR）对膨润土（CK）和150BS-12修饰土（150BS-12）吸附金属离子前后进行表征,通过批处理法研究不同比例BS-12修饰膨润土对Cu²⁺和Pb²⁺在单一及Cu-Pb复合体系中的平衡吸附特征和差异,并探讨金属离子在修饰土样上的交互作用机制.结果表明,供试土样在单一及复合体系中对Cu²⁺和Pb²⁺的吸附量均呈150BS-12> 100BS-12> 50BS-12> CK的顺序,吸附均符合Freundlich和Langmuir模型; BS-12修饰更有利于Cu²⁺的吸附,但Pb²⁺在BS-12修饰土样上的吸附量及选择性系数均大于Cu²⁺; Cu-Pb复合体系中,两种金属离子存在相互拮抗的作用,BS-12修饰在减弱Pb²⁺对Cu²⁺的拮抗作用的同时增强了Cu²⁺对Pb²⁺的拮抗作用,但Pb²⁺对Cu²⁺的拮抗作用仍大于Cu²⁺对Pb²⁺的拮抗作用;温度升高、p H升高和离子强度降低均能增加对Cu²⁺和Pb²⁺的吸附,但其对两种金属离子的影响程度不同,也导致对金属离子间的交互作用产生影响.更多还原

【Abstract】 Amphoteric modification can simultaneously improve the adsorption of organic pollutants and heavy metals on clay minerals.Study of the adsorption and interaction of multiple heavy metals on amphoteric modified soils is therefore of practical significance.Here,bentonite-（ CK） and 150 BS-12-modified bentonites（ 150 BS-12） were characterized both before and after metal ion adsorption using Fourier-transform infrared spectroscopy（ FTIR）. The equilibrium adsorption characteristics and differences of Cu²⁺and Pb²⁺in single and binary systems were studied by batch methods. The interaction mechanism of the metals on modified bentonites is also discussed. The results showed that the adsorption capacity of Cu²⁺and Pb²⁺in single and binary systems was ranked,in descending order,as 150 BS-12 > 100 BS-12 > 50 BS-12 > CK,and that the adsorption isotherm could be described by the Langmuir and Freundlich equations. Although the modification of BS-12 was more beneficial for the adsorption of Cu²⁺,the adsorption capacity and selectivity coefficient of Pb²⁺on BS-12-modified bentonites were larger than for Cu²⁺. Cu²⁺and Pb²⁺had a mutually antagonistic effect on each other; modification with BS-12 enhanced the effect of Cu²⁺on Pb²⁺and weakened the effect of Pb²⁺on Cu²⁺,which was always stronger than the effect of Cu²⁺on Pb²⁺. Increases in temperature and p H,and a reduction in ionic strength,can increase the adsorption of Cu²⁺and Pb²⁺; however,the influence of these factors varied between the two metals,which also affected the interaction between the metals.更多还原