Adsorption of p-Arsanilic Acid on Iron (Hydr)oxides and Its Implications for Contamination in Soils

Because of the diversification industries in developing cities, phenomenon simultaneous contamination various kinds pollutants is becoming common, and environmental process multi-contaminated mediums has attracted attention recent years. In this study, p-arsanilic acid (ASA), a kind organic arsenic feed additive that contains group chemical structure, used as typical contaminant to investigate its adsorption on iron oxides implication for contaminated soils. The kinetics all solids can be fitted pseudo-second-order kinetic model well. At same mass dosage conditions, amount per unit surface area follows order α-FeOOH > γ-Fe2O3 α-Fe2O3, which significantly higher than actual soil, because lower content soil. Lower pH conditions favor ASA adsorption, while inhibit result electrostatic repulsion weakened hydrophobic interaction. presence phosphate also inhibits competitive effect. Correlations between soil Fe2O3 content, total phosphorus matter are investigated work, moderate positive correlation (R2 = 0.630), strong negative 0.734), insignificant 0.099), no 0.006) found, respectively. These findings would help evaluate potential hazard usage additives, well further understanding geochemical processes contaminants complicated mediums.