Abstract
Adsorption and preconcentration of chromate species from water and wastewater were investigated using carminic acid modified anion exchanger (IRA 900). The existence of some oxyanions which might have a competing effect on chromate removal such as MoO42-, SO42, SeO42, and AsO42 was investigated beside the influence of pH. Adsorption reached equilibrium within 30 min and was independent of initial concentration of chromate oxyanions. Studies were performed at different pH values to find the pH at which maximum adsorption occurred and was determined to be at a pH between 4.0 and 4.5. The Langmuir adsorption capacity (q(max)) was found to be 19.27 mg Cr(VI)/g of the adsorbent. The results showed that modification of IRA 900 with carminic acid is suitable for the removal of Cr (VI), as chromate, from water and wastewater samples. The obtained material was subjected to efficient regeneration.