Fluoride is a poison that accumulates in our bones. It has been associated with cancer in young males; osteoporosis; reduced I.Q; and hip fractures in the elderly, to name a few. The permissible limit of fluoride concentration in drinking water is 1.5mg/L according to WHO guidelines. Therefore, knowledge of its removal, using best technique with maximum efficiency is needed. Among various techn...

A variable order kinetic (VOK) model derived from the Langmuir equation was applied to specify the kinetics of the fluoride removal reaction for electrocoagulation (EC). Synthetic solutions were employed to elucidate the effects of the initial fluoride concentration, the applied current and the initial acidity on the simulation results of the model. The proposed model successfully describes the...

A new medium, eggshell powder has been developed for fluoride removal from aqueous solution. Fluoride adsorption was studied in a batch system where adsorption was found to be pH dependent with maximum removal efficiency at 6.0. The experimental data was more satisfactorily fitted with Langmuir isotherm model. The kinetics and the factor controlling adsorption process fully accepted by pseudo-s...

a bioreactor equipped with hollow fiber microfiltration membranes was applied for wastewater treatment. removal of chemical oxygen demand (cod) and biochemical oxygen demand (bod5) was investigated. the experimental setup consisted of influent and effluent tanks, and membrane modules using polyvinyl di–fluoride (pvdf) hollow fibers. the operation program included suction and backwash steps whic...

The natural coagulant Moringa oleifera (MO) is considered to be an efficient coagulant with some advantages over chemical coagulants. Fluoride removal, using MO seed extract was investigated. The influence of MO dosage, initial F concentration, and pH were determined and modeled using the Box-Behnken design response surface methodology. With a constant initial F concentration, it was found that...

Fluoride is one of the anionic contaminants which is found in excess in surface or groundwater because of geochemical reactions or anthropogenic activities such as the disposal of industrial wastewaters. Among various methods used for defluoridation of water such as coagulation, precipitation, membrane processes, electrolytic treatment, ion-exchange, the adsorption process is widely used. It of...

The ability of activated alumina and activated carbon to remove Fluoride from aqueous solution has been investigated. The studies were carried out as functions of contact time, concentration and pH. The data indicate that activated alumina surface sites are heterogeneous in nature and that fits into a heterogeneous site binding model. The optimum pH for complete removal of Fluoride from aqueous...

We describe a novel combustion synthesis for the preparation of Nanomagnesia (NM) and its application in water purification. The synthesis is based on the self-propagated combustion of the magnesium nitrate trapped in cellulose fibers. Various characterization studies confirmed that NM formed is crystalline with high phase purity, and the particle size varied in the range of 3-7nm. The fluoride...