Solar oxidation and removal of arsenic from water: An experimental study

Abstract

Arsenic poses a significant threat to both human health and the environment. Arsenic removal through solar oxidation has been investigated in a batch process. Arsenic was artificially added to both deionized and tap water to conduct the experiments. Clean, colorless, transparent, Polyethylene Terephthalate (PET) bottles were used for Solar Oxidation and Removal of Arsenic (SORAS) experiments. Various parameters including concentration of arsenic, iron, and photo-catalyst were varied during the experiments.The maximum arsenic removal efficiency obtained was 94% and 88% for deionized water and tap water respectively when ferrous ammonium sulphate and lemon juice were used. Maximum efficiency of 88% and 82% was obtained for deionized and tap water respectively when locally available ferrous alum and glacial acetic acid were used. The change in volume of the photo-catalyst (lemon juice and glacial acetic acid) also did not affect the SORAS process significantly. Therefore, the recommended volume for the photo-catalyst was 1-2 ml/L. SORAS can very well be used for areas contaminated with arsenic having concentrations less than 100 µg/L.

Arsenic removal using iron oxide nanoparticles produced employing a green synthesis approach

“…No change was observed after the contact time was increased from 120 min to 24 h, hence, all further experiments were conducted with a contact time of 120 min. A similar trend for arsenic adsorption by nanoparticles prepared from rice husk (Pillai et al., 2020) and iron oxide nanoparticles modified activated carbon (Ha et al., 2021) has been observed in previous studies. Adsorption occurs in a short duration, adsorption sites get saturated, and no removal occurs after saturation (Mohan et al., 2019).…”

“…Many technologies are available for removing arsenic from water. Various techniques, including oxidation, co‐precipitation, coagulation, adsorption, ion‐exchange, and membrane technologies, have been used for the treatment of contaminated groundwater or surface water (Alka et al., 2021; Hering et al., 2017; Kushwaha et al., 2023; Mohan et al., 2022; Mohanty, 2017; Ng et al., 2004; Nicomel et al., 2016; Thirunavukkarasu et al., 2007). Adsorption has been the most widely employed technique because of its ease of operation, high removal capacity, high adsorption capacity, cost‐effectiveness, safe disposal, and high surface area (Gupta et al., 2009).…”