Paper Title
Effect of Chemical Treatment with Phosphoric Acid on the Adsorption Capacity of Cork Waste Powder for Hexavalent Chromium

Abstract
The aim of this work is to study the influence of chemical treatment on the adsorption capacity of a local agricultural waste. Cork waste powder already demonstrated its affinity on hexavalent chromium adsorption. However, this faculty had to be improved by using treatments with chemicals such as phosphoric acid. Different phosphoric acid concentrations ewer investigated for 1/1 (cork powder/phosphoric acid) volume ratio were investigated. The treatment gave encouraging results resumed in this paper. Equilibrium time was found to be 50 min with a pseudo-second order kinetics, solution pHhad ne effect on hexavalent chromium biosorption on cork by-product treated with phosphoric acid. Adsorption was monolayer with L isotherms type at an optimal temperature of 40°C. Keywords - Adsorption, Hexavalent Chromium, Cork Waste, Chemical Treatment, Adsorption Isotherms.