A comparative study of kinetics of methylene blue dye using adsorbent andisol and humic acid from lighnite by KOH-hydrothermal method

Abstract

A comparative study of adsorption kinetics model of methylene blue (MB) dye using andisol and humic acid (HA) adsorbents from the isolation of lignite with KOH-Hydrothermal has been carried out. The adsorption process was measured by using a UV-Vis Spectrophotometer to determine concentration of the adsorbed MB. The adsorption kinetics was determined using the first-order Langmuir-Hinshelwood kinetic model, the first-order kinetic model of Lagergren (1898), and the pseudo-second-order kinetic model of McKay and Ho. The adsorption kinetic model of MB on andisol and HA followed second-order kinetic model of McKay and Ho, with the reaction rate constant for MB adsorption on andisol higher than the rate constant for MB adsorption on HA. The reaction rate constant for MB adsorption on andisol was 0.0532 g mg-1 minute-1 and the adsorption capacity was 18.9753 mg/gr, while the reaction rate constant for MB adsorption on andisol was 0.0241 g mg-1 minute-1 and the adsorption capacity was 19.7628 mg/gr.