Arsenic(III) removal performances in the absence/presence of groundwater occurring ions of agglomerated Fe(III)–Al(III) mixed oxide nanoparticles

Abstract

Performances of As(III) adsorption by agglomerated nanoparticles of calcined (250 °C) hydrous Fe(III)–Al(III) mixed oxide (NHIAO-250 °C) were investigated at 30 °C and pH 7.0 in the absence/presence of background ions occurring in groundwater. Kinetics and equilibrium data described, respectively, the pseudo-second order and the Langmuir isotherm equations well. Higher (15–35%) monolayer capacity (58.30 ± 3.15 mg g −1) of As(III) system in absence of any background ions implied the adverse influence of the incorporated ions over As(III) sorption. Increased entropy (positive Δ S°) was responsible for the endothermic reactions (positive Δ H°) and spontaneous nature (Δ G° = negative). Thomas model described the fixed-bed breakthrough curves of As(III) removal from spiked groundwater well.