Development of a cost-effective technique to remove the arsenic contamination from aqueous solutions by calcium peroxide nanoparticles

In the present study, we synthesized calcium peroxide nanoparticles and evaluated them as an innovative oxidant to remove As (III) from contaminated water samples. The CaO2 nanoparticles were 15–25 nm in diameter identified by TEM. Oxidation occurred within minutes and CaO2 nanoparticles effectively removed total As between natural pH conditions (6.5 and 8.5). Experiments were performed to investigate the influence of CaO2 nanoparticles concentration, pH of solution and contact time on the efficiency of arsenic removal. Up to 88% removal efficiency for arsenic was obtained by nanoparticles dosage of 40 mg/L at time equal to 30 min and pH 7.5. It could be concluded that the removal efficiency was enhanced by increasing CaO2 nanoparticles dosage and reaction time, but decreased by increasing arsenic concentration and pH for nano sized CaO2. These results suggest that CaO2 nanoparticles may be used to develop a simple and efficient arsenic (III) removal method.

► Nano-sized CaO2 makes it more effective material for removing total arsenic from water.
► Removal efficiency was enhanced with increasing CaO2 nanoparticles dosage and reaction time.
► The maximum removal of total arsenic is found to be about 91% in average at pH 6.5.
► The CaO2 nanoparticles may be used as remediation agent for removal of arsenic.