以二乙烯三胺( DETA)为改性剂,对多壁碳纳米管(MWCNTs)进行共价键修饰,合成了一种对Au(Ⅲ)和pd(Ⅱ)有选择性的吸附剂MWCNTs-DETA,并对Au(Ⅲ)和Pd(Ⅱ)的吸附参数进行了研究和优化.结果表明,最佳洗脱剂浓度为1.0 mol/L硫脲-1.0 mol/L盐酸,Au(Ⅲ)和Pd(Ⅱ)的洗脱率分别为94.48％和89.06％,最佳条件下Au(Ⅲ)和Pd(Ⅱ)的饱和吸附容量分别为50.45和25.68 mg/g.在对吸附等温线的考察中,Au(Ⅲ)拟合Langmuir等温线较好,而Pd(Ⅱ)则拟合Freundlich等温线较好.吸附动力学均拟合二级模型较好.%2,2'-Diaminodiethylamine(DETA) covalently modified multi-walled carbon nanotubes(MWCNTs-DETA) were synthesized and used for the adsorption of Au ( Ⅲ) and Pd (Ⅱ). The experimental parameters affecting the adsorption capacities were studied and optimized. The highest elution ratios were determined as 94. 48% for Au(Ⅲ) and 89. 06% for Pd(Ⅱ) using 1. 0 mol/L thiourea-hydrochloric acid solution as the eluent. Under the optimal experimental conditions, the maximum adsorption capacities for Au ( Ⅲ) and Pd(Ⅱ) were 50.45 and 25. 68 mg/g, respectively. Langmuir isotherm model agreed well with the equilibrium experimental data of Au (Ⅲ) while Freundlich isotherm model agreed with those of Pd (Ⅱ). Adsorption kinetics of Au( Ⅲ) and Pd( Ⅱ ) could be well described by the pseudo-second-order model.
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