Patent ID: 7247242
Filing Date: 2007-07-24
Classification: C02F,Y10S

Abstract:
1. A continuous process for reducing the concentration of arsenic in water to below an acceptable level and for recycling magnesium, comprising: a) adding magnesium hydroxide to the water; b) adsorbing arsenic on the magnesium hydroxide; c) separating and removing from the water the magnesium hydroxide with adsorbed arsenic, thereby reducing the concentration of arsenic in the water to below the acceptable level; d) making an aqueous solution comprising the magnesium hydroxide with adsorbed arsenic removed in step c); e) converting the magnesium hydroxide with adsorbed arsenic to magnesium carbonate, whereupon free arsenic is released into the solution; f) separating and removing the magnesium carbonate from the solution; g) heating the magnesium carbonate to produce carbon dioxide and purified magnesium oxide; and h) providing the purified magnesium oxide produced in step g) to step a), whereby the magnesium is recycled.