Journal of Chemical Technology and Biotechnology, Vol.75, No.4, 279-284, 2000
Comparison of different sorbents (inorganic and biological) for the removal of Pb2+ from aqueous solutions
In an attempt to evaluate the suitability of activated sludge for Pb2+ removal, a comparative study was carried out using several chemical adsorbents and three types of biomass. The order of Pb2+ removal capacities for chemical adsorbents was found to be: ion exchange resin > zeolite > granular activated carbon (GAC) > powdered activated carbon (PAC), while for biomass the order was Aureobasidium pullulans > Saccharomyces cerevisiae > activated sludge. Although Pb2+ removal capacity (mg Pb2+ g(-1)) of the activated sludge (30.9) was lower than those of the ion exchange resin (167.7) and other pure cultures of A pullulans (170.4) and S cerevisiae (95.3), it was higher than those of other chemical adsorbents such as GAC (26.0), PAC (2.1), and zeolite (30.2). The initial Pb2+ removal rates for the chemical adsorbents were in the order of PAC > GAC > zeolite > ion exchange resin, while for the biomass samples it was A pullulans > activated sludge > S cerevisiae. The initial Pb2+ removal rate of activated sludge was higher than those of GAG, zeolite, ion exchange resin and S. cerevisiae cells. Therefore, it was concluded that activated sludge that has been used in a municipal wastewater facility can be effectively used in heavy metal removal processes, in situ.
Keywords:SACCHAROMYCES-CEREVISIAE;EXTRACELLULAR POLYMERS;ACTIVATED-SLUDGE;HEAVY-METALS;BIOSORPTION;ACCUMULATION;BIOMASS;IONS;ARRHIZUS;CELLS