Impact of thermal treatment on bentonite retention ability toward nickel and silver retention.

In this work, a natural bentonite was submitted to heating treatment (at 550°C and 750°C) in order to correlate such treatment to an improvement of the metal adsorption properties. The characterization of all materials includes XRD, FTIR, TGA, SEM analysis and porosity measurements. The efficiency of raw and calcined bentonite to remove nickel and silver from aqueous solution was highlighted and fell in the upper range when compared to material of similar composition taken from the literature. Raw and bentonite calcined at 550°C properties toward metal retention remained in such upper range of efficiency when tested in complex effluents like industrials wastewaters. [ABSTRACT FROM AUTHOR]