Assessment of alkalinity on the adsorption of cadmium ion using KOH-activated carbon from Sesame stem

Abstract

The increase alkalinity on the adsorption of cd2+ using KOH-activated carbon from Sesame stem was studied. Determination of metal ion in solution shows adsorption capacities of 86.68 % for KOH-AC at saturated state. Effect of metal ion concentration shows that, Removal efficiency of Cd2+ by KOH-AC increases with increasing presence of the adsorbate due to the availability of adsorption sites on the activated carbon. Increase acidity general favors the adsorption. The effect of pH shows that the adsorption of cadmium ions increases with increasing acidity between the pH of 7.5 to 6. However, as the Cd2+ concentration becomes exceedingly high, the removal efficiency decreases. A general observation was that before equilibrium, there is rise in the removal efficiency of Cd2+ by KOH-AC with increasing contact time which is universally true for good adsorbents. Effect of metal ionic strength shows that activated carbon adsorption decrease with increase in ionic strength in any acidic medium.

Effect of HNO3 activated carbon on the decreasing basicity for cadmium ion sorption

“…To investigate the initial metal ion concentration on sorption capacity, different sample consisting of 50 ml of the metal ion concentration from 10ppm, 20ppm, 40 ppm, 60 ppm, 100 ppm, but each containing 2g activated carbon sesame stem were prepared and shaken for 1hour until equilibrium was obtain. The synthetic wastewater was filtered and analyzed for residual metal ion concentration using AAS [10].…”

“…From Figure 1, it was observed that HNO3 activated carbon shows a significant sorption of 84.48 % of the cadmium ions. Mikyitsabu et al, [10] studied the sorption of sesame stem by KOH-AC, the result show that the equilibrium adsorption was attained after about 1 hour with adsorption capacities of 84.48 KOH-AC. Aghdas et al [11] revealed the impregnation ratio of the activating agent which highly influenced the surface area and the porosity development during preparation.…”

“…Aghdas et al [11] revealed the impregnation ratio of the activating agent which highly influenced the surface area and the porosity development during preparation. Mikyitsabu et al, [10] found out that activated carbon prepared at low and intermediate impregnation ratios showed higher yields. This could be attributed to the decomposition of the polymeric structures of the activated carbons during the activation stage that release most elements different from carbon (N, H and O).…”