Application of Synthetic Iron Oxyhydroxide with Influencing Factors for Removal of As(V) and As(III) from Groundwater

Abstract

Synthesized iron oxyhydroxide was applied for the adsorptive removal of As(V) and As(III) from the aquas media. Additionally, this investigation highlighted the synergistic effect of calcium carbonate in conjunction with iron oxyhydroxide, resulting in enhanced removal efficiency. The experiment was conducted under various conditions: concentration, dosage, pH, agitation, and temperature. Material characterizations such as Brunauer Emmett Teller, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy were implied to understand adsorption mechanisms. The Langmuir model revealed optimal concentrations for As(V) = 500 µg/L at pH-5 and As(III) = 200 µg/L at pH-7, resulting in 95% and 93% adsorption efficiencies, respectively. Maximum adsorption capacities “q_m” were found to be 1 266.943 µg/g for As(V) and 1 080.241 µg/g for As(III). Freundlich model demonstrated favorable adsorption by indicating “n > 1” such as As(V) = 2.542 and As(III) = 2.707; similarly, the speciation factor “R_L < 1” for both species as As(V) = 0.1 and As(III) = 0.5, respectively. The kinetic study presented a pseudo-second-order model as best fitted, indicating throughout chemisorption processes for removing As(V) and As(III). Furthermore, incorporating calcium carbonate presented a significant leap in the removal efficiency, indicating As(V) from 95% to 98% and As(III) from 93% to 96%, respectively. Our findings offer profound motivation for developing effective and sustainable solutions to tackle arsenic contamination, underscoring the exceptional promise of iron oxyhydroxide in conjunction with calcium carbonate to achieve maximum removal efficiency.