米糠对水中Cr(Ⅵ)的吸附机理

摘要

利用米糠吸附水中Cr(Ⅵ),分别对总Cr、Cr(Ⅵ)浓度和pH进行了定量测定,探讨了米糠对Cr(Ⅵ)吸附机理.结果表明,Cr(Ⅵ)是以HCrO4-形态通过静电吸引作用被吸附,在吸附过程中同时存在氧化还原和离子交换的作用机理.另外,分析了米糠经化学修饰前后的吸附效果和红外光谱,发现经化学修饰后的米糠对Cr(Ⅵ)吸附能力下降,且米糠中的胺基和羧基在吸附过程中起重要作用.%The adsorption mechanisms of rice bran on Cr (VI) were investigated. The total Cr and Cr (VI) concentration and pH in aqueous solution were quantitatively analyzed. Cr (VI) was adsorbed with the form of HCrCV by electrostatic attraction accompanied with oxidation-reduction and cation exchange process during the adsorption. In addition, the results of adsorption effect and FTIR spectroscopy of the chemically modified rice bran indicated that the adsorption ability of modified rice bran on Cr (VI) was decreased; and the hydroxy and amido played great role in the process of adsorption.