BIOSORPTION OF BINARY MIXTURE OF COPPER AND COBALT BY FREE AND IMMOBILIZED BIOMASS OF PENICILLIUM CYCLOPIUM

Batch sorption equilibrium experiments using free and immobilized in poly(vinyl alcohol) (PVA) hydrogel biomass of Penicillium cyclopium were carried out using binary mixture of corresponding metal ion solutions. Metal binding ability of the hybrid hydrogel for Cu(II) and Co(II) was determined by using atomic absorption spectrophotometer. The performance of free and immobilized biosorbent was evaluated by sorption kinetics and sorption capacities for different metal ions in the mixture. Immobilized system showed higher removal efficiency (expressed as mg metal ions removed per mg metal ions added) in comparison to the free cells system. The pseudo-second order kinetic model was applied to the experimental data and important kinetic parameters of the biosorption process were calculated. The data obtained are in agreement with the assumption that the external mass transfer limitation in the immobilized system can be neglected and the biosorption process is chemisorption controlled.