BIOSORPTION OF CR(VI), PB(II) AND ZN(II) FROM AQUEOUS SOLUTIONS BY IMMOBILISED PHANEROCHAETE CHRYSOSPORIUM BIOMASS IN A FIXED-BED COLUMN

摘要

The continuous-flow adsorption of Cr(VI), Pb(II) and Zn(II) from aqueous solution by immobilisedrnPhanerochaete chrysosporium biomass in a fixed-bed column was studied. The effects of flow rate,rninfluent concentration of Cr(VI), Pb(II) and Zn(II) and bed depth on breakthrough curves andrnbiosorption capacity were investigated. The experimental results showed that the breakthrough timerndecreased with increasing flow rate, increasing influent concentration and decreasing bed depth.rnThe data also indicated that the equilibrium uptake of Cr(VI), Pb(II) and Zn(II) increased withrndecreasing flow rate and increasing influent concentration of Cr(VI), Pb(II) and Zn(II). Two modelsrnwere employed to predict the breakthrough curves and to determine the characteristic parametersrnof the column useful for column design. The Thomas model was able to predict the breakthroughrncurve in the range of relative concentration(Co/Ci) higher than0.3, Cr(VI), Pb(II) and Zn(II) whereasrnthe validity of the Bohart-Admas model was limited to the initial part of breakthrough curve at allrnflow rates and influent concentrations of Cr(VI), Pb(II) and Zn(II). The feasibility of reusing thernimmobilised fungal beads through five adsorption/desorption cycles in fixed-bed column wasrninvestigated.