Technologies for Arsenic Removal from Contaminated Water Sources

The majority of established arsenic removal technologies can be divided into three main categories, depending on the specific mechanism that is responsible for removing arsenic. These categories are usually referred as coagulation–precipitation, membrane, and sorption processes. Three processes in this group have been developed for arsenic removal; aluminum or iron coagulation, lime softening, as well as a combination of iron and manganese removal with arsenic. Two types of membrane processes remove arsenic efficiently from water sources: reverse osmosis and electrodialysis. Adsorption processes are another category of arsenic removal technologies; they are based on the adsorption of arsenic onto suitable adsorbing media. Two different technologies have been applied to remove arsenic, activated alumina and ion exchange. Keywords: arsenic; removal methods; treatment; contaminated water; coagulation; membrane; sorption; biological oxidation; chemical oxidation; speciation