Arsenic is a naturally occurring element found in soil and groundwater. Arsenic concentrations vary according to geographical location. When arsenic levels are found to be too high in water to be used as drinking water, it may be necessary to treat this water with an arsenic treatment filter to remove arsenic.
Arsenic is generally found in two different forms or values in a natural environment, depending on the amount of oxygen present in the groundwater. In shallower aquifers with higher oxygen levels, arsenic is usually found as arsenate. In deeper, anaerobic groundwater, arsenic is usually found as arsenite. In the pH range 4 to 10, the predominant arsenic compound is neutral, while Arsenate species are negatively charged. Arsenite removal efficiencies are generally lower than arsenate due to the negative charge of arsenate. In many cases, it may be necessary to oxidize arsenite to arsenate for arsenic removal and efficient arsenic filtration in drinking water. Arsenic filters are treatment systems that work on the principle of absorption of arsenic, which is often oxidized to arsenate.