Reuse of activated sludge biomass: I. Removal of basic dyes from wastewater by biomass

The removal of basic dyes from wastewater was studied using activated sludge biomass as an adsorbent. The experimental results of COD removal (%) showed that for various basic dyes, adsorption by biomass was not only feasible but also effective. The kinetics of adsorption followed first-order processes, controlled by film diffusion. Influences on adsorption capacity of various factors, such as chemical structure, basicity and molecular weight of basic dye molecules were investigated. The effects of temperature on adsorption of Basic Violet 3 dye were studied and adsorption capacity decreased with increasing temperature. The process was exothermic in nature and the activation energy was 3.27 kcal mol (-1). (C) 2002 Elsevier Science Ltd. All rights reserved.