核桃壳负载纳米零价铁吸附废水中Pb^(2+)

A Study on the Adsorption of Pb^(2+) in Wastewater by Walnut Shell Supported-Fe^0

以核桃壳粉、NaBH4、FeCl2·4H2O为原料,采用液相化学还原法制备了核桃壳负载纳米零价铁,并用红外光谱(FTIR)、X射线粉末衍射(XRD)、透射电镜(TEM)进行了表征,研究了负载纳米零价铁核桃壳作为吸附剂对水溶液中Pb2+的吸附。结果表明,293 K时,在pH=5,初始质量浓度为200 mg/L的水溶液中,10 mg吸附剂对Pb2+离子的最大吸附量为199.90 mg/g。动力学实验表明,该吸附行为符合二级动力学方程,吸附等温线能较好地符合Langmuir等温方程式。

The walnut shell-supported nanoscale zero-valent iron （walnut-nZVI） was prepared from NaBH4, FeCl2·4H2O and walnut shell by liquid phase chemical reduction. The materials were characterized by means of FTIR, XRD and TEM. The adsorption of Pb2 ＋ in aqueous solution by walnut- nZVI was investigated. The results indicate that the maximum adsorption capacity for Pb2＋ was 199.90 mg/g at 293 K,pH 5.0 and the amount of the adsorbent was 10 mg when the initial concentration of Pb2＋ was 200 mg/L. The adsorption kinetics data indicate that the adsorption fitted well with the pseudo-second-order kinetic model. The adsorption isotherms of Pb2＋ could be well described with the Langmuir equation.