Kinetic Evaluation on the Adsorption of Reactive Black 5 on Used Black Tea Leaves

Abstract

Kinetics of the adsorption of reactive black 5 from aqueous solution on used black tea leaves (UBTL) was studied in batch process. The
influence of concentration and temperature on the kinetics of adsorption was investigated. The adsorption of reactive black 5 on UBTL
follows pseudo second order kinetics at all concentrations. It also moderately follows the elovich model equation within the experimental
range of concentrations. The adsorption equilibrium could not be attained during six hours of contact time. The equilibrium adsorption
capacity and pseudo second order rate constant were calculated from the valid pseudo second order kinetics. The elovich model equation
was used to calculate the desorption constant to evaluate the adsorption affinity. The amount adsorbed increases with increasing
temperature, indicating the chemical nature of adsorption.