Optimization of activation parameters for enhanced pollutant removal: A case study of avocado peel–derived activated carbon

Abstract

With the increasing demand for affordable and eco-friendly solutions to water pollution, researchers are turning to agricultural waste as a promising resource. This study explores how avocado peels often discarded as waste can be transformed into effective activated carbon for treating hydrocarbon-contaminated water. Using zinc chloride (ZnCl₂ ) as the activating agent, we tested different preparation conditions to find the most efficient combination. The best results were obtained using 1.0 mol/dm³ ZnCl₂ , a 1:2 impregnation ratio, carbonization at 550°C, and a heating time of 2.5 hours. Under these conditions, the avocado peel–derived carbon achieved the highest iodine adsorption capacity of 16.5 mg/g, indicating strong potential for pollutant removal. When applied to hydrocarbon-polluted water, this activated carbon significantly reduced key pollutants such as COD, BOD, TDS, turbidity, and heavy metals. Most of the treated water’s parameters fell within the acceptable limits set by EGASPIN and DPR guidelines. The findings not only highlight the environmental benefits of converting fruit waste into useful materials but also present a practical, low-cost solution for communities affected by oil pollution. This research supports the use of avocado peels as a sustainable option for water purification, offering both environmental and economic advantages, especially in oil-producing regions like the Niger Delta.