Synthesis of Cr(VI)-adsorbed carbon from Artocarpus heterophyllus peel waste: activated conditions, characterizations and adsorption isotherm

Abstract

Abstract Lignocellulosic biomass is often activated with phosphoric acid to make value-added goods. However, statistical effects of impregnation ratio (IR) and activation temperature (AT) on Artocarpus heterophyllus peel-derived activated carbon have not been studied. This study used an experimental approach and regression model to investigate these impacts on Cr(VI) adsorption capacity. A regression model and analysis of variance assessed these two factors’ variation. The activated carbon’s morphology, surface functional groups, and Cr(VI) adsorption isotherm at optimal conditions were examined using Brunauer, Emmett and Teller, X-ray diffraction, Scanning Electron Microscopy, Fourier Transform Infrared Spectrometry, Boehm titration, pH drift methods, Langmuir, and Freundlich models. The quadratic regression model described the influence of AT and IR on Cr(VI) adsorption capacity and found the best values of 545°C and 4:1. When IR and AT ranged from 1.89 to 4.0 and 330°C to 545°C respectively, the combined effect caused the most variance and had a synergistic effect on Cr(VI) adsorption capacity. This activated carbon at optimal conditions had many carboxylic groups, a porous, amorphous surface, and a maximum mono-layer capacity of 29.498 mg g-1. Freundlich is a better Cr(VI) adsorption model. This study will give a technical way and advocate for the utilization of activated carbon derived from Artocarpus heterophyllus peel as an effective material for the removal of chromium (VI) from water.