ABSTRACT
Heavy metal adsorption (zinc, lead, and cadmium) from contaminated water was achieved using modified ogbono shells. Following the activation of the adsorbent, the bulk density and pH were found to be 1.00 and 9.68, respectively, indicating qualities of an effective adsorbent. Functional groups such as carboxyl, amine, hydroxyl, and carbonyl were visible in the Fourier Transform Infrared Spectrometer. The results of the adsorption experiments indicated that the percentage adsorbed rose as these parameters increased. For lead, zinc, and cadmium ions, the percentage adsorbed increased from 80 to 90.36, 87.20 to 96.75, and 83.60 to 93.16 as the concentration increased from 10 to 50 ppm, respectively. The percentages adsorbed for lead, zinc, and cadmium ions increased from 86.24 to 97.52, 80.72 to 92.80, and 79.88 to 90.44 as the contact time increased from 10 to 60 minutes, respectively. The percentage adsorbed for lead, zinc, and cadmium ions increased from 92.32 to 97.16, 93.76 to 99.16, and 92.76 to 98.17 respectively, as the adsorption dosage increased from 0.2 to 1.0 g. The Freundlich adsorption isotherm was favourable, as seen from the R² values. The R² value for the modified ogbono adsorbent in the adsorption of lead ions was 0.925; the R² value for the modified ogbono adsorbent in the adsorption of zinc ions was 0.962; and the R² value for the modified ogbono adsorbent in the adsorption of cadmium ions was 0.903.
