Absorption of methylene blue from aqueous solutions on activated coal CAN-9: kinetics and equilibrium studies

Abstract

The adsorption of methylene blue and kinetics of its adsorption from aqueous solutions on activated carbon CAN-9, obtained from walnut shells by chemical activation with orthophosphoric acid were studied. It has been shown that methylene blue adsorption isotherm from aqueous solutions on CAN-9 in the linear coordinates of the Langmuir model is a straight line (R = 0.99427) and is of Langmuir type. The kinetics of methylene blue adsorption on CAN-9, measured at two initial concentrations, showed an increase in Kint and C values with the increase of the initial concentrations. The process of intra-particular diffusion occurs in only one stage and takes place in the mesopores.