A Review of Arsenic Removal Methods from Water Resources

Many of the pollutants in water are known to be harmful for human health and toxic for environment. Among these pollutants, Arsenic is more important because millions of people are exposed to contaminated drinking water. The World Health Organization (WHO) has identified the permitted limit of below 0.01 mg/L (10 micrograms per liter) for arsenic in drinking water and the same amount for arsenic has been reported in Iran's 1053 standard. In this study, various techniques have been investigated for removing Arsenic and efficiency of different nanoparticles in treatment of Arsenic from drinking water. Common methods of removing Arsenic from water sources are including oxidation, coagulation and flocculation, reverse osmosis and ultrafiltration, ion exchange, phytoremediation and new technologies based on the use of nanoparticles. The findings showed that despite of the high arsenic removal percentage using different methods such as oxidation, ion exchange and floating with dissolved air, these methods are not economic and a lot of time is required to achieve optimal efficiency. Recently, the use of nanoparticles has become very popular, so that metal oxide nanoparticles such as magnetic iron, Zinc, Copper, Serum, and Aluminum can completely eliminate Arsenic soluble with a high concentration of 50 mg/L in water sources and after the adsorbent is saturated, it is possible to use the regeneration of adsorbents, repeatedly by adsorbing the pollutant into the adsorbent. As a result, the use of nanoparticles is better than chemical processes and is economic due to their high efficiency in a short time.