Effective Removal of Arsenic with Lanthanum(III)- and Cerium(III)-loaded Orange Waste Gels

Orange waste has been chemically modified and loaded with lanthanum(III) and/or cerium(III) to examine its adsorption behavior to both As(V) and As(III). Arsenate removal was found to be favored over a pH range of 6 ∼ 9.5 while arsenite removal took place at pH values ranging from 9 to 11. The maximum sorption capacity of the gel for As(III) removal was evaluated as 43 mg/g, while that for As(V) was 42 mg/g. Column-mode tests using the La(III)-loaded gel confirmed a complete removal of As(V). A reasonably high adsorption potential within the design criteria makes the present gel an alternative choice for arsenic removal.