Removal of arsenic(III) from aqueous solution by china clay

Abstract

The present investigation describes the use of china clay for the removal of As(III) from aqueous solution at different concentrations, retention times, temperatures and pH of the solution. The process of removal follows first order rate expression and the uptake of adsorbate within the pores of china clay is also diffusion controlled. The equilibrium data of As(III) at various temperatures follow Langmuir isotherm. The mass transfer coefficient (^ßL) of As(III) diffusion has been determined at 20°, 30° and 40°C. Maximum removal was found at pH 8. In order to understand the mechanism of As(III) removal by china clay, thermodynamic parameters were calculated.

Key words:

• China clay
• adsorption
• retention time
• diffusion
• intraparticle transport
• mass transfer coefficient
• Langmuir isotherm
• thermodynamic parameters
• pH.