Elimination d’un colorant par un biomatériau

Abstract

The aim of this work is to study the removal of a dye by a biomaterial, using a practical and less expensive physico-chemical process. The dye used in our work is safranin powder. The process used in this study to remove the safranin dye from an aqueous solu-tion is adsorption. The adsorbent material used is shrimp shell (marine waste) known as CRV. The solid was characterised by FTIR and the experimental results were analysed using the BET model. The experimental results on the effect of pH obtained show that the elimination of safranin by adsorption on the material is effective and significant at high pH lev-els (basic pH), particularly at pH 12 where it exceeds 90(mg/g). Since safranin is a cationic dye, this explains the strong interaction between the negatively charged material (pH>pHpzc) and the dye at high pH levels. Modelling of the adsorption isotherms of the safranin dye by the CRV material at the two temperatures studied, 25°C and 35°C, shows strong elimination of the dye. The BET model simulates the adsorption isotherm favourably at 35°C, prov-ing that adsorption is easier at higher temperatures than 25°C.