MOLYBDENUM SORPTION BY MICROBIAL BIOMASS

Biomass of a wide range of microorganisms has been shown to be capable of molybdenum sorption from solutions. Rhizopus arrhizus biomass was the most active, exhibiting both high capacity (180 mg Mo/g) and high affinity for molybdenum. The process of molybdenum biosorption was pH- dependent and proceeded most effectively within a pH range of 1.5 - 2. 5. Upon pH increase biomass capacity decreased abruptly and molybdenum sorption hardly proceeded at pH 6 - 8. The sorbed molybdenum could be completely desorbed from biomass at pH 8 - 10. Microbial biomass was established to be capable of recovering molybdenum from solutions with high selectivity. At Mo : Me ratio equal to 7:10, such cations as Cr3 +, Al3+, CU2+, and Zn2+ lowered the capacity by no more than by 20 - 3 0%, the metals themselves being not sorbed.