COMPARISON OF CA-ALGINATE AND IMMOBILIZED Z-RAMIGERA AS SORBENTS FOR COPPER(II) REMOVAL

Zoogloea ramigera was immobilized to Ca-alginate in order to obtain higher adsorption capacity and yields in a packed column operated in continuous mode. The adsorption of copper(II) ions to Ca-alginate and immobilized Z. ramigera in the packed column was investigated as a function of flow rate and inlet-metal-ion concentration Copper adsorption in the immobilized-cell column was initially limited by diffusion of the solute through the pores. The initial removal of copper by the immobilized micro-organism system was therefore lower than initial removal of copper by the Ca-alginate system, but equilibrium-copper-removal percentages and total-copper-removal percentages were higher than those of Ca alginate. When column loading was selected as 50 mg litre, total copper removal by immobilized Z. ramigera and Ca-alginate was obtained as 94.3% and 63.8% of presented metal, respectively, after 5184 ml of flow at a flow rate of 3.6 ml min(-1). At inlet-metal-ion concentrations higher than 100-150 mg litre(-1) and at higher flow rates, a lower metal-uptake capacity and early saturation were observed. Metal recovery from immobilized Z. ramigera and Ca-alginate was achieved in 0.005 M H2SO4 at pH 2.0.