Kinetics of acid dye adsorption on GAC

This work involves the treatment of simulated industrial waste water containing acid dye-stuffs 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.