Arsenite [As(III)] is more toxic and more difficult to remove from water than arsenate [As(V)]. For enhanced As(III) removal from water, a new nanostructured Ce-Mn binary oxide with a Ce/Mn molar ratio of 3:1 was fabricated via a facile one-step oxidation-coprecipitation method at ambient temperature. The synthetic Ce-Mn binary oxide is amorphous with a high surface area of 157 m²/g. Cerium (Ce) and manganese (Mn) in this oxide exist mainly in the oxidation state of Ce(IV) and Mn(IV), respectively. It can effectively oxidize As(III) to As(V) and efficently adsorb the formed As(V). Moreover, this sorbent exhibits an obviously synergistic effect. The maximal sorption capacity of As(III) is 97.7 mg/g, which is competitive with most of reported sorbents. The As(III) uptake is rapid and slightly affected by tested solution pH, ionic strength, dissolved organic matters and coexisting anions except for phosphate, indicating the high selectivity toward arsenic. The arsenic-loaded Ce-Mn binary oxide could be readily regenerated and repeatedly used. Both Mn and Ce oxides in sorbent are responsible for As(III) oxidation, and the Ce oxide is dominant for adsorbing formed As(V) during As(III) removal. The oxide could be used as an attractive sorbent for As(III) removal from contaminated water, because of its facile and low-cost synthesis process, good As(III) sorption performance, and reusability.

与砷酸盐[As（V）]相比，砷酸盐[As（III）]毒性更大，更难以从水中去除。为了增强从水中去除As（III）的能力，通过一种简便的一步氧化共沉淀方法，在环境温度下制备了一种新的Ce / Mn摩尔比为3：1的纳米结构Ce-Mn二元氧化物。合成的Ce-Mn二元氧化物是无定形的，具有157 m ²的高表面积/G。该氧化物中的铈（Ce）和锰（Mn）分别主要以Ce（IV）和Mn（IV）的氧化态存在。它可以有效地将As（III）氧化为As（V），并有效地吸附所形成的As（V）。而且，这种吸附剂表现出明显的协同作用。As（III）的最大吸附容量为97.7 mg / g，与大多数已报道的吸附剂竞争。As（III）的吸收迅速，并受测试溶液的pH，离子强度，溶解的有机物和除磷酸盐以外的共存阴离子的影响很小，表明对砷的高选择性。砷负载的Ce-Mn二元氧化物可以容易地再生并重复使用。吸附剂中的Mn和Ce氧化物都负责As（III）的氧化，而Ce氧化物在As（III）去除过程中对形成的As（V）的吸附起主要作用。