Kinetics of acid dye adsorption on GAC

This work involves the treatment of simulated industrial waste water containing acid dyestuffs with granular activated carbon adsorption selected as the treatment method. Predicting the rate at which adsorption takes place for a given system is probably the single most important factor for adsorber design, with adsorbate residence time and ultimately the reactor dimensions controlled by the system’s kinetics. A fixed volume stirred tank reactor was used to study the kinetics of adsorption in a single component system. Process parameters including the rate of agitation, dye concentration and phase ratio were studied with results being modelled using a dual resistance external mass transfer and solid diffusivity model. A single value of solid diffusivity described the adsorption decay curves in most instances and also indicated that chemisorption is the likely process of acid dye adsorption onto activated carbon.