Methylene blue removal by durian rind derived charcoal adsorbent

Abstract

Abstract Textile wastewater is characterized by its strong color and high chemical content, including contaminants such as dyes that negatively impact ecosystems. One example of a chemical dye commonly released is methylene blue (MB). Adsorption is one of the methods used to treat textile wastewater. Durian rind (DR), an agricultural waste, can be converted into sustainable carbon through a carbonization process. As a carbon material, DR has the potential to serve as an adsorbent. This study evaluates the potential of DR as an adsorbent for MB removal from solution. DR is converted into charcoal through pyrolysis and subsequently activated using sulfuric acid (H 2 SO 4 ). DR, durian rind charcoal (DRC), and durian rind activated charcoal (DRAC) are tested for MB removal using a batch adsorption process. The process is optimized using the one-factor-at-a-time (OFAT) method. MB concentration is determined by UV-Vis spectrometry. The maximum MB removal efficiencies achieved by DR, DRC, and DRAC are 78.37%, 98.57%, and 98.95%, respectively, under optimal conditions: pH 6, 60 min. of contact time, 180 rpm agitation speed, 1 g adsorbent dosage, and an initial MB concentration of 100 mg/L. The Langmuir and Freundlich models are studied to determine the adsorption behavior, with results indicating that the adsorption process follows the Freundlich model (R 2 = 0.9427). Pseudo-first-order and pseudo-second-order kinetic models are applied to describe the adsorption rate, with findings showing that the pseudo-second-order model best fits chemisorption (R 2 = 0.9832). This study concludes that DR can be used as an effective alternative adsorbent for color removal in textile wastewater while also addressing the issue of DR waste.