球形木质素负载纳米零价铁去除溴酸盐的研究

Removal of Bromate Using Nanoscale Zero-valent Iron Supported on Spherical Lignin

以球形氰乙基木质素为原料通过液相还原法制备球形木质素负载纳米零价铁材料(LSAC-Fe),用于去除饮用水中微量的溴酸盐。采用场发射扫描电子显微镜(FESEM)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、氮气吸附法(BET)等对其结构进行表征,并探究了不同条件下LSAC-Fe对BrO_3^-的吸附效果及其热力学吸附和去除机理。研究表明,纳米零价铁可较为均匀地负载在球形木质素上,并且LSAC-Fe具有很高的表面活性;BrO_3^-的去除率随着初始溶液p H值的升高而降低,随着BrO_3^-初始溶液质量浓度的增加而降低;LSAC-Fe对BrO_3^-的吸附过程为吸热过程,升温可促进LSAC-Fe对BrO_3^-的吸附。

In order to remove the tracebromate in drinking water,nanoscale zero-valent iron supported on spherical lignin(LSAC-Fe)was synthesized through liquid-phase reduction method using spherical cyanoethyl lignin as raw material.The LSAC-Fe was characterized by field emission scanning electron microscopy(FESEM),X-ray diffractometer(XRD),X-ray photoelectron spectroscopy(XPS)and nitrogen adsorption(BET).The adsorption effect of LSAC-Fe on BrO-3 under different conditions was investigated,and the thermodynamic adsorption and removal mechanism were studied.The results showed that the nanoscale zero-valent iron was distributed homogeneously on the spherical lignin,and LSAC-Fe had a high surface activity.The removal percentage of BrO-3 decreased with the increase of the initial pH of the solution of and the initial concentration of BrO-3.The BrO-3adsorption process of LSAC-Fe was the endothermic process,and the temperature rise was beneficial to the adsorption of BrO-3 on LSAC-Fe.