In this study, the adsorption kinetics and equilibrium of methylene blue from aqueous solution onto activated carbon derived from coffee husk using one step ZnCl2 activation were investigated. The influence of initial methylene blue concentration and temperature were evaluated employing the batch experiment. To the experimental data, different kinetics and isotherm models were applied, finding that the best fitted is the pseudo-second-order equation and the Redlich-Peterson model, respectively. | HNUE JOURNAL OF SCIENCE DOI Natural Sciences 2020 Volume 65 Issue 6 pp. 116-129 This paper is available online at http KINETIC AND EQUILIBRIUM STUDY ON THE ADSORPTION OF METHYLENE BLUE FROM AQUEOUS SOLUTION ONTO COFFEE HUSK ACTIVATED CARBON Ta Huu Son1 Le Van Khu1 Luong Thi Thu Thuy1 Vu Thi Huong1 Le Huu Dung1 and Nguyen Dinh Hung2 1 Faculty of Chemistry Hanoi National University of Education 2 Vinh Phuc Gifted High School Abstract. In this study the adsorption kinetics and equilibrium of methylene blue from aqueous solution onto activated carbon derived from coffee husk using one step ZnCl2 activation were investigated. The influence of initial methylene blue concentration and temperature were evaluated employing the batch experiment. To the experimental data different kinetics and isotherm models were applied finding that the best fitted is the pseudo-second-order equation and the Redlich-Peterson model respectively. The mechanism of the adsorption was examined using the Weber and Morris model and the obtained results suggested that the intra-particle diffusion was not the only rate-controlling step. The scale-up system was also designed for 50 - 90 methylene blue removal from an initial concentration of 100 mg L 1 at 30 C. Keywords activated carbon methylene blue adsorption kinetics equilibrium of adsorption. 1. Introduction Currently water pollution with organic compounds is becoming an increasing concern issue by scientists and society. Dyes are used in many industries for dyeing printing painting food coloring and reported to cause eye burn vomiting cyanosis jaundice cancer allergy mutation etc. Numerous techniques including biological treatment adsorption filtration coagulation photodegradation etc are being developed. Among these methods adsorption is a non-toxic cost-effectiveness approach especially at low adsorbate concentration or large scale applications 1 . Various adsorbents have been used for dye .
