ARSENIC REMOVAL FROM HOUSEHOLD DRINKING WATER BY ADSORPTION

• Published in: Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering Toxic/hazardous substances & environmental engineering, 2002-10, Vol.37 (9), p.1721-1736
• Main Authors: Yuan, Tao, Yong Hu, Jiang, Ong, Say Leong, Luo, Qi Fang, Jun Ng, Wern
• Format: Article
• Language: English
• Subjects: Adsorption; Arsenic; Arsenic - analysis; Arsenic - chemistry; Arsenic removal; Beads; Calcium carbonate; Charcoal - chemistry; China; Contamination; Drinking water; Environmental engineering; Gels - chemistry; Household Articles; Household drinking water; Households; Iron; Iron - chemistry; Iron-oxide coated sand; Mathematical models; Public health; Sand; Silicon Dioxide - chemistry; Water hardness; Water Pollutants, Chemical - analysis; Water Purification - instrumentation; Water Purification - methods; Water quality; Water Supply - standards; Water utilities; Wells
• ISSN: 1093-4529; 1532-4117
• DOI: 10.1081/ESE-120015432

Geogenic inorganic arsenic contamination in drinking water has been raising public health concern especially in developing countries. Cost-effective and stopgap arsenic removal method for household use (cooking and drinking) is very urgent. Several iron treated natural materials such as Fe-treated activated carbon (FeAC), Fe-treated gel beads (FeGB) and iron oxide-coated sand (IOCS), were investigated in this study for arsenic removal from dispersed household drinking water supply (scattered wells in the endemic arsenic poisoning areas). IOCS showed consistently good performance in terms of As(III) and As(V) removal in batch tests, column tests and field experiment. As(V) adsorption decreased slightly but As(III) adsorption maintained relatively stable when the pH value was increased from 5 to 9. In strong hardness water (612.5 mg/L CaCO 3 ), As(III) adsorption efficiency was noted to decrease. The adsorption data obtained in column test fitted well to the Langmuir isotherm model. The adsorbent recovery efficiency was above 94% when using 0.2 N NaOH regenerated the columns. In addition, 200 L of product water was produced by the household device (containing 3.0 kg IOCS produced) when the influent arsenic concentration ranging from 0.202 to 1.733 mg/L was encountered during the field experimental study conducted in Shanyin County, China. Neither the iron leaching nor other water quality deterioration was observed. It was noted in this study that IOCS is a promising medium for arsenic removal from household drinking water supplies.