Removal of Ga(III) from aqueous solution by adsorption on activated bentonite using a factorial design

The purpose of the work is to study the adsorption of gallium(III) on bentonite from aqueous solutions. The important parameters, which affect the adsorption, such as pH of solution, mass of bentonite and temperature have been investigated. The results of parameters study showed that when pH and mass of bentonite increase there was a significant increase of Ga(III) at 20°C and the optimum conditions were as follows: pH of solution (2.50), mass of bentonite (3.50 g) and temperature (20°C). An experimental test carried out using a factorial design 23 indicated that pH and mass of bentonite have a positive effect, whereas temperature has negative effect. The interaction effect between pH and mass of bentonite was an important significant factor for gallium adsorption.