铅对铁铝复合氧化物吸附铜的影响

Influence of Lead on Adsorption of Fe-Al Binary Oxide for Copper

复合氧化物对环境中的金属离子具有较高的吸附容量。但2种或多种金属离子共存条件下,复合氧化物的吸附行为仍缺乏全面的了解。本文通过批吸附试验方法,研究溶液中有无Pb^(2+)共存时,铁铝复合氧化物对Cu^(2+)吸附容量的影响。结果表明,当溶液中不存在Pb^(2+)时,Cu^(2+)在铁铝复合氧化物表面的Qmax为149.08 mg·g^(-1)。当溶液中Pb^(2+)和Cu^(2+)共存时,Cu^(2+)的Qmax降低到28.81 mg·g^(-1)。在pH值3～7的范围内,随着溶液pH值的升高,Cu^(2+)在铁铝复合氧化物表面的吸附量呈现逐渐增加的趋势。此外在相同的pH值条件下,Pb^(2+)的存在减少了吸附在氧化物表面的Cu^(2+)量。存在或不存在Pb^(2+)的情况下,Cu^(2+)在氧化物表面上的吸附动力学均遵循Elovich方程,并且在约120 min时达到吸附平衡。

Binary oxide have a strong adsorption capacity for heavy metals.But the adsorption behavior of binary oxide was unclear,when there were more than two heavy metals exist.In this paper,the adsorption of Cu^2+by Fe-Al binary oxide in the presence of Pb^2+were studied by batch adsorption experiment.Results showed that the maximum adsorption amounts of Cu^2+by Fe-Al binary oxide at 25℃were 149.08 mg·g^-1.The maximum adsorption capacity of Cu^2+reduced to 28.81 mg·g^-1 when Pb^2+was introduced into the solution.In the range of pH 3~7,adsorption amount of Cu^2+by Fe-Al binary oxide increased with solution pH increasing.Cu^2+adsorption kinetics on Fe-Al binary oxides was in accordance with the Elovich equation,and the adsorption capacity reached the adsorption equilibrium at about 120 min.