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为了研究吸附法对饮用水中As(V)的深度净化,采用原位生成法,将FeOOH和MnO2纳米粒子负载到硅胶上,成功地合成了两种吸附剂(S-FeOOH和S-MnO2).吸附剂的表征表明,S-FeOOH和S-MnO2具有较大的颗粒尺寸(粒径150～250μm),由于其特殊的非晶和多孔结构,使其具有较高的比表面积(357.0和334.6 m2/g).在间歇实验中,研究了pH、接触时间、吸附剂用量、温度对吸附剂吸附性能的影响.将实验结果与其他吸附剂相比,本研究合成的吸附剂,特别是S-FeOOH,在较宽的pH(2～12)和温度(25～65°C)范围内,均表现出良好的As(V)去除性能.在被S-FeOOH处理的砷污水中,As(V)的残留浓度约为0.01 mg/L,达到了饮用水标准.吸附过程遵循伪二级动力学模型,在5 min内吸附达到平衡.S-FeOOH的平衡吸附数据可通过Langmuir等温线拟合,而S-MnO2的吸附过程遵循Freundlich模型,说明它们具有不同的吸附机理.结果表明,S-FeOOH在去除As(V)方面优于S-MnO2,即S-FeOOH可作为一种有发展前景的吸附剂用于饮用水中As(V)的深度净化.“,”For deep purification of As(V) from drinking water by adsorption, two adsorbents S-FeOOH and S-MnO2 were successfully synthesized by loading FeOOH and MnO2 nanoparticles onto silica gel in situ. Characterization of the adsorbents implied that S-FeOOH and S-MnO2 with large particle size (diameter of 150?250 μm) still had high specific surface areas (357.0 and 334.6 m2/g) due to their specific amorphous and porous structure. In batch experiments, the influences of pH, contact time, adsorbent dosage, and temperature on the adsorption were investigated. Comparing with other adsorbents reported, the synthesized adsorbents in this study, especially S-FeOOH, showed good performance for As(V) removal in a wide pH (2?12) and temperature (25?65 °C) range. The residual As(V) concentration after S-FeOOH treatment was around 0.01 mg/L, which met the drinking water standard. The adsorption process followed the pseudo-second-order kinetic model, and the adsorption equilibrium was reached within 5 min. The equilibrium adsorption data of S-FeOOH can be well fitted by the Langmuir isotherm, while that of S-MnO2 followed Freundlich model, which indicated their different adsorption mechanisms. The results show that S-FeOOH is superior to S-MnO2 in eliminating As(V), and S-FeOOH could be used as a promising adsorbent for the deep purification of As(V) in drinking water.