Katsoyiannis Ioannis A, Althoff Hans Werner, Bartel Hartmut, Jekel Martin
Department of Drinking Water, Federal Environmental Agency (Umweltbundesamt), Research Site Marienfelde, Schichauweg 58, 12307 Berlin, Germany.
Water Res. 2006 Nov;40(19):3646-52. doi: 10.1016/j.watres.2006.06.032.
In this study, we investigated the effect of groundwater composition on the sorption of U(VI) onto bacteriogenic iron oxides (BIOS) and synthetic ferrihydrite (HFO). The concentration of carbonate was found to be the key factor controlling U(VI) sorption onto both BIOS and HFO. However, the efficiency of HFO to adsorb uranium(VI) was higher than that of BIOS at pH 7.0. The pH value also played an important role on the U(VI) sorption onto iron oxides. U(VI) sorption onto BIOS was optimum in the pH range 3-4.5, whereas in the same pH range, the ability of HFO to adsorb U(VI) was very low. HFO was very efficient in adsorbing U(VI) in the pH range 4.5-6.5. Zeta potential measurements have been employed to understand the different removal trends between BIOS and HFO. BIOS had a negative surface charge across the whole pH range examined, in contrast to HFO, which had point of zero charge 7.6. The sorption results have been incorporated in a surface complexation model, which predicted adequately the pH-dependent sorption of U(VI) onto both types of iron oxides.
在本研究中，我们调查了地下水成分对U(VI)在生物成因氧化铁（BIOS）和合成水铁矿（HFO）上吸附的影响。发现碳酸盐浓度是控制U(VI)在BIOS和HFO上吸附的关键因素。然而，在pH 7.0时，HFO吸附铀(VI)的效率高于BIOS。pH值对U(VI)在氧化铁上的吸附也起着重要作用。U(VI)在BIOS上的吸附在pH范围3 - 4.5时最佳，而在相同pH范围内，HFO吸附U(VI)的能力非常低。HFO在pH范围4.5 - 6.5内非常有效地吸附U(VI)。已采用zeta电位测量来了解BIOS和HFO之间不同的去除趋势。与具有零电荷点7.6的HFO相反，BIOS在所研究的整个pH范围内具有负表面电荷。吸附结果已纳入表面络合模型，该模型充分预测了U(VI)在两种类型氧化铁上的pH依赖性吸附。
