Kinetics Investigation of Methylene Blue Adsorption on Activated Carbon Derived from Coffee Husk Wate

Abstract

Methylene Blue (MB) is a colored substance that pollutes the environment and can cause poisoning if inhaled. Adsorption using activated carbon offers a promising solution to this pollution. This study aims to determine the optimum contact time and adsorbent mass for methylene blue adsorption using coffee husk activated carbon. It also analyzes the adsorption kinetics, including reaction order and reaction rate constant. This study employed an experimental research design with a quantitative approach. The methodology involved manufacturing actived carbon from coffee husk waste through carbonization and acetic acid activation, followed by tests for water and ash content. Subsequent stages focused on determining the optimum adsorbent mass (0.03g; 0.05g, 0.10g, and 0.15g) and optimum contact time (30, 60, 90, 120, and 150 minutes). Results indicated an activated carbon water content of 8.6% and an ash content achieving 4.6%. the optimum adsorbent mass was 0.1g, achieving 84.80% adsorption efficiency, while the optimum contact time was 90 minutes, with an efficiency of 84.45%. adsorption kinetics analysis revealed that the process followed a second-order kinetic model, caharacterized by an R² value of 1 and a rate constant of 0.00167 M^-1.minutes^-1.