Sorption of aqueous fluoride by active silica-carbon from rice husk

Department of Chemical Technology, University of Calcutta, 92, Acharya Prafulla Chandra Road,

Kolkata-700 009, India

E-mail: rabin.majumdar@gmail.com        Fax: 91-33-23519755

Manuscript received 7 February 2008, accepted 4 April 2008

Fluoride in drinking water in excess of desirable levels has been a serious threat to public health in many places in India. Distilled water containing 5 ppm fluoride (dissolved as NaF) passed through a glass column (2.5 em id) packed with 10 g of iron-impregnated active silica-carbon composite char derived from rice husk, yielded treated water with fluoride concentrations between 1 and 2.5 ppm, that are desirable as per drinking water standards in India and elsewhere.