Author(s)

S. S. Al-Shahrani

Abstract

This research project investigates the application of Saudi activated clay (bentonite) to remove nickel from aqueous solutions. The removal characteristics of nickel ions from aqueous solution using Saudi activated bentonite were investigated under various operating variables like shaking time, solution pH, clay dosage and initial metal concentration. The results showed that the sorption of nickel ions on Saudi activated clay was relatively fast and the equilibrium was reached after 40 min. They also showed that increasing the initial nickel concentration decreased nickel removal percentage due to the saturation of clay with nickel ions. Furthermore, the adsorption of nickel increases from 70 to 100% with an increase in solution pH from 2.0 to 9.0. The adsorption isotherm data were well fitted with both the linearized Langmuir and Freundlich models. Nickel adsorption onto Saudi activated bentonite was well represented by the pseudo-second-order kinetic model. Keywords: removal of nickel, Saudi bentonite, adsorption of nickel, heavy metals removal, adsorption isotherm, adsorption kinetic. 1 Introduction Effluent wastewaters from processes such as electroplating, metal finishing, metallurgical, chemical manufacturing and battery manufacturing industries contain toxic substances, metal acids, alkalis, and other substances. Removal of heavy metals such as nickel from aqueous solutions is necessary because of the frequent appearance of these metals in waste streams. This problem has received considerable attention in recent years due primarily to concern that those heavy metals in the waste streams can be readily adsorbed by marine animals and

Keywords

removal of nickel, Saudi bentonite, adsorption of nickel, heavy metals removal, adsorption isotherm, adsorption kinetic