Cr VI Removal by Using Agricultural Waste (Modified Canola Meal & Crude Canola Meal) from Aqueous Solutions: Kinetic, Isotherm and Thermodynamic Study

Abstract

Metal Cr and CrIII components usually are not harmful but CrVI is poisonous in case it is swallowed. Half of a tea spoon of Cr VI is fatal. Plating industry and waste waters polluted with CrVI are considered as one of the most im-portant sources of its exposal and emission. Today Bio- absorbents are sub-jects of studies to resolve the above issues. This paper is to study kinetic, isotherm and thermodynamic analysis of Cr adsorption via applying canola meal. Effective parameters in adsorption such as: pH, contact time, adsor-bent dose, temperature and initial concentration of CrVI metal are consid-ered as independent variables and final concentration of Cr VI is considered as dependent variable. Changing one variable while keeping other variables constant is a basic principle in every experiment. The best adsorption effi-ciency of crude canola was obtained in pH 7 and for canola modified with CTAB in pH 2. The optimum dose of adsorbent for both crude and modified canola was equal to 0.150g/L. also the best contact time was 60 minutes. Maximum adsorption obtained in 12.5 mg/lit CrVI concentration and in 60°c. With respect to capacity of Cr VI adsorption in canola meal it can be applied to remove the CrVI and similar pollutants from water and waste water.