Nano-bentonite as a low-cost adsorbent for removal of mercury from aqueous solution

Abstract

Study of the adoptive of mercury removal (Hg II) from aqueous solution was investigated by low-cost nanoparticle bentonite. Nanoparticle bentonite was prepared by the heating method at a temperature of 400 °C. The activation was carried out by immersed of natural bentonite in sodium hydroxide. The resulting powder was heating in the present of nitrogen gas as an activator agent. The bentonite sample was characterized by means of Scanning Electron Microscopy (SEM) and Brunai Emmet Teller (BET). The prepared bentonite had a heterogeneous surface with a particle size of 100-300 nm. The nano-bentonite was then tested in the absorption of Hg2+ synthetic were varied of the initial concentration (Co) from 5 to 400 ppm with 0.2 gram absorbent and 100 ml solution. The Hg2+ absorption amount was analysed using Atomic Absorption Spectroscopy (AAS). The adsorption capacities were fully fit with Freundlich isotherm models. It was found that the adsorption process followed the Freundlich isotherm model with n value of 1.9577 and Kf of 8.3985. Therefore, using the low-cost nano-bentonite is a potential adsorbent for removal of mercury from water solution.