Rapid Development of Activated Carbon and ZnO Nanoparticles via Green Waste Conversion Using Avocado Fruit Peel Powder and its High Performance Efficiency in Aqueous Dye Removal Application

Abstract

The present study focused to evaluate the utility of avocado fruit peel waste material for the development of activated carbon and ZnO nanoparticles for water treatment applications. Green synthesized activated carbon and ZnO nanoparticles using avocado fruit peel as a substrate was characterized using different techniques including FESEM, TEM, EDX, XRD and FTIR. In addition, further investigation was carried out to find their efficiency of its application for removal of selective dyes such as Congo red, Crystal violet, Saffranin, Methylene orange and Malachite green in aqueous solution through adsorption and photocatalytic activity respectively. 99.9% dye removal was observed in the column experiment condition, where, 100 mg L−1 concentrations of selective dye solutions were passed through the column (7.9 × 1.2 cm) filled with 50 mg of synthesized activated carbon at the flow rate of 6 drops/min. Green synthesized ZnO nanoparticles exhibited efficient photocatalytic activity of 70–98% against above mentioned selective dyes under the sunlight irradiation for the experimental condition which contains 20 mg of ZnO-NPs and 50 mL (30 mg L−1) of each dye solution. Further studies are recommended to elucidate the detailed mechanism of this avocado fruit peel powder in proposed materials conversion and using these materials as an agent for dye removal applications.