Removal Of Fluoride From Drinking Water by Electrosorption

Abstract

Fluoride in drinking water is known for both beneficial and detrimental effects on health. Contamination of drinking water due to fluoride is a severe health hazard problem in many parts of the world. Fluorosis a disease caused by ingestion of fluoride in excess through water, food, and air is a serious health problem. According to UNESCO (status January 2007) more than 200 million people worldwide rely on Drinking Water with fluoride concentrations higher than the present WHO guideline value. More than 20 developed and developing nations endemic for fluorosis. In India, first detected in Nellore district of A.P. in 1937. Water with Required Amount of Fluoride: 0.6 mg/litre to 1.5 mg/litre. The detrimental effects of excessive fluoride can be controlled by defluoridation of natural waters. A number of methods of defluoridation are available; however not all the methods are suitable for all circumstances and hence proper justification is required for selection an appropriate method for a given situation. Certain under-exploited but abundantly available materials like activated alumina have indicated excellent potential for fluoride uptake. Electrosorption (adsorption + electric potential) seems to be promising for the effective removal of fluoride. The main objective of study is to develop the efficient fluoride removal technique based on Electrosorption using activated alumina. Electrosorption technique has shown the enhanced fluoride removal efficiency compared to that with conventional adsorption. The optimization of the process was achieved under various experimental parameters like Fluoride concentration, electric potential, volumetric flow rate, and pH for both batch and continuous operation mode. The comparison of the performance of the Electrosorption system proved to be more efficient than conventional alumina process in removing fluoride from water. iii The enhanced efficiency with Electrosorption system was due to simultaneous regeneration of activated alumina. Therefore Electrosorption process coupled with adsorption of fluoride on activated alumina column can be used effectively for the fluoride removal from drinking water.