Fig. 2: Effect of solution pH on Pb speciation and uptake, biosorption kinetics, and adsorption isotherm.
From: Lead removal at trace concentrations from water by inactive yeast cells
a Distribution of Pb(NO3)2 hydrolysis products at 25 oC and 1 μM Pb(NO3)2. b Increase in solution pH due to yeast biomass addition; error: ± 0.06 pH units. c Effect of initial pH of solution on Pb2+ uptake for 5 mg of yeast biomass and C0 of 100 ppb Pb2+. The final pH of solutions after biosorption is reported for each case; error: ± 0.06 pH units. d Kinetic experiments of 5 mg yeast biomass with C0 of 100 ppb Pb2+, indicating the rapid biosorption process; qt: Pb2+ uptake capacity of yeast biomass at different time intervals (μg of Pb2+ by g of biomass). Time course micrographs of lyophilized S. cerevisiae cells incubated in the same aqueous solution at 0 h and 24 h are shown in the inset, validating that there is no cell growth or division during the experiments (scale bar: 8 μm). e Adsorption isotherm at 25 oC, following the Langmuir adsorption isotherm model; qe: Pb2+ uptake capacity of yeast biomass at equilibrium (μg of Pb2+ by g of biomass). f Pb2+ percentage removal versus Pb2+ C0.
