The Efficacy of Banana Peel Activated Carbon in the Removal of Cyanide and Selected Metals from Cassava Processing Wastewater

The purpose of this study is to investigate the effectiveness of banana peel activated carbon as an adsorbent in the removal of cyanide and selected metals from fresh cassava wastewater collected from the discharge pit. Fresh banana peels were dried, adequately prepared and treated with 0.1 M HCl. Batch experiments were conducted by varying the adsorbent dose from 5 – 20 g and contact time between 10 – 360 minutes to determine the optimum percentage removal of cyanide - CN and selected metals (lead - Pb, chromium - Cr and cadmium - Cd) from the wastewater. Adsorption percentage was found to be proportional to contact time and dosage. Maximum removal percentage of the cyanide and metals at pH 7.2 was 96.45%, 15 g adsorbent in 300 minutes for CN, 98%, 20 g adsorbent in 240 minutes for Pb, 98%, 20 g adsorbent in 180 minutes for Cd while with 5 g adsorbent, initial traces of Cr in the wastewater was no longer detected. The effectiveness of the activated banana peel carbon increases with dosage at different contact time for cyanide and the selected metal removal. Thus, at 20 g adsorbent dose and contact time of 300 minutes cyanide and metal ions investigated could not be detected, indicating complete removal. Results indicated the best fitted model as the coefficient of determination (R2) obtained for the adsorption capacity was 0.93, 0.98, 0.84 and 0.93 for CN, Pb, Cr and Cd respectively. Banana Peel Activated Carbon can efficiently treat cassava wastewater containing multi-ions.