中文摘要：

表生环境中,吸附是硒进入固相沉积环境的重要途径之一。为了厘清硒氧阴离子团吸附行为及其影响因素,本文选择赤铁矿、二氧化锰和氧化铝作为吸附剂,采用批次实验的方法,研究了溶液pH、硒浓度以及反应时间等对硒的吸附影响。结果表明：为了达到较理想的吸附效果,溶液的pH应控制在4~6之间,在室温、pH为5时,赤铁矿、二氧化锰和氧化铝对亚硒酸盐的饱和吸附量分别约为1.62×10-3、0.33×10-3和1.07×10-3,对硒酸盐的饱和吸附量分别约为1.0×10-3、0、0.55×10-3;其吸附规律均符合Langmuir等温吸附方程,且理论最大吸附量与实验得出的最大吸附量基本一致。运用准一级动力学、准二级动力学、Elvoich方程和颗粒内扩散模型4种动力学模型对实验数据进行拟合,发现硒吸附过程运用准二级动力学方程表示时相关性最好,表明了硒氧阴离子团在铁、锰、铝氧化物表面的吸附过程较为复杂,可能涉及表面物理吸附和颗粒扩散等过程。

英文摘要：

Adsorption is one of the most important pathways for selenium （Se）infiltrating the solid deposits in supergene environment. In order to clarify the adsorption behavior of Se oxyanions and its influencing factors, we selected hematite, manganese dioxide and aluminum oxide as adsorbents, and applied batch experiments to research the effects of pH, Se concentration and contacting time on adsorption. Results show that the optimum pH range for attaining maximum adsorption should be 4-6. At pH= 5 and room temperature, the maximum selenite adsorptions of hematite, manganese oxide and aluminum oxide are approximately 1.62 ×10-3 , 0. 33 ×10-3 , and 1.07 × 10-3 , respectively while the maximum selenate adsorption of hematite, manganese oxide and aluminum oxide are approximately 1.0x10-3, 0.0~ 10-3, and 0.55 ~ 10-3, respectively. These adsorptions completely fit with the Langmuir isotherm and the stoichiometric adsorptions are close to the maximum adsorptions. The pseudo-first and pseudo-second order, Elvoich equations and intra-particle diffusion models were used to fit the experimental data, indicating that the pseudo-second-order kinetics model could best describe the adsorption behaviors. This result demonstrates that the adsorption process of SeO3-2/SeO4^2- on Fe/Mn/Al oxide surface are complicated, which may involve surface physical adsorption and particle diffusion.