Photocatalytic process for total arsenic removal using an innovative BiVO 4 /TiO 2 /LED system from aqueous solution: Optimization by response surface methodology (RSM)

Abstract

A photocatalytic process was studied for total arsenic removal using an innovative BiVO 4 /TiO 2 /LED system from aqueous solution. Optimization of the experiments was also performed via response surface methodology (RSM). In this respect, characteristics of the catalysts were determined by XRD, FE-SEM, EDX, FT-IR, BET, and DRS spectra. Several catalysts were further compared and then the best and efficient photocatalyst for arsenic removal was selected using one-at-the-time experiments. The impacts of four variables were subsequently studied through designing experiments by central composite rotatable design (CCRD). Optimization of the process variables was also fulfilled and the effect of intervening factors on the given system was investigated using optimum conditions for maximum arsenic removal efficiency (99.97) including initial arsenic concentration of 3 mg/L, initial pH by 4.5, reaction time of 120 min, and catalyst dosage by 0.2 g/100 mL. Thus, this innovative BiVO 4 /TiO 2 /LED system could be utilized as an effective way to remove arsenic-contaminated water. © 2019 Taiwan Institute of Chemical Engineers