Adsorption of Pb(II) ions from synthetic wastewater (aqueous solution) using treated banana peel as adsorbent: article

Water pollution becomes one of the major concerns in Malaysia nowadays. One of the sources that contribute to the water pollution is industrial wastewater that contains heavy metals. Lead, nickel and copper are the heavy metals that commonly found in wastewater. There are some conventional methods to treat the wastewater such as chemical precipitation, reverse osmosis and ion exchange; however, they are less efficient and high in cost. The recent study indicates that adsorbent from agricultural waste materials has a potential in removing metals in the wastewater. Thus, the purpose of this study is to investigate the ability of treated banana peel as a good low-cost adsorbent to remove heavy metal which is lead from lead (II) nitrate solution. The effect of adsorbent dosage and contact time on the adsorption rate has been carried out. To prepare the adsorbent, the banana peel was cut into smaller pieces and dried in an oven first before it grounded into powder. Then, it has been soaked in citric acid solution and rinsed until it achieved pH 5.5. Dried treated banana adsorbent powder was mixed with lead (II) nitrate in two different situations which are different adsorbent dosage and contact time. The final concentration of lead in the solution was measured by using Atomic Absorption Spectrometer (AAS) and the percentage of lead removal was calculated. The results showed that the percentage of lead removal increases as the adsorbent dosage increases. The maximum percentages obtained in this study were 22.6%, which is at 3.0g of adsorbent dosage and 9.2% at 90 minutes of contact time. It also indicates that the longer the contact time of the adsorption, the higher the percentage of lead removal can be achieved. Therefore, treated banana peel does show some potential as low-cost adsorbent.