Adsorption of Metals (Fe(II) , Cr(III) and Co(II)) from Aqueous Solution by Using Activated Carbon Prepared from Mesquite Tree

Abstract

Mesquite tree was use to prepare activated carbon through chemical activation method with 1 M KOH and under temperature of 600 0 C for 1 hr , the product of the activated was examined for its proximate composition ; ash content (3.9%) , moisture content (3%), carbon content (40.65%) , volatile matter (25.65%) , porosity (54.95%) , iodine number of 13.22 and methylene blue value of 166.6 mg/g. XRF study on activated carbon prepared from Mesquite tree (ACM)shows different concentration of inorganic elements the major elements in the sample are Potassium (0.301%) ,Calcium (0.357%),Zinc(0.01366%) and Ferrous (0.687%).XRD analysis showed the presence of highly organized crystalline structure of raw activated carbon for ACM sample , Carbon with crystalline structure of Rhombohedral and Carbon Supplied with crystalline structure Orthorhombic and Cubic were detected. The result showed a strong and broad adsorption peak at 1577.66 cm -1 , which corresponds to the lactone in ACM sample. While other strong and broad adsorption peak appeared at 1340 cm -1 , which corresponds to the Phenol Aliphatic CH 2 and CH 3 was observed at 2920 cm -1 . The kinetics of adsorption of metals Fe 2+ , Cr 3+ and Co 2+ from aqueous solution has also been investigated. The adsorption process was carried out in isothermal container at 30 O C. the effect of dose of activated carbon prepared from the sample on percentage removal metals indicate that the maximum dose of adsorbent was at concentration of 0.8 g/l for sample , The contact time was in 80 min for the samples . The adsorption decreased as the pH increase the optimum pH for the adsorption was attended at 6 for ,the experimental isotherm data were analyzed using Freundlich equations. The adsorption process follows the Freundlich order kinetic, having a correlation coefficient (R 2) of 0.99(Fe 2+), 0.43(Cr 3+) and 0.90 (Co 2+).Adsorption capacity was high for Fe 2 + metals compared to capacity of 3.45 and 2.616 for Cr 3+ and Co +2 respectively , adsorption intensity was higher for Co 2+ (9.51) than that obtained for Fe 2+ (2.91).