BIOSORPTION OF URANIUM BY CROSS-LINKED AND ALGINATE IMMOBILIZED RESIDUAL BIOMASS FROM DISTILLERY SPENT WASH

Residual biomass from a whiskey distillery was examined for its abilit y to function as a biosorbent for uranium. Biomass recovered and lyoph ilised exhibited a maximum biosorption capacity of 165-170 mg uranium/ g dry weight biomass at 15 degrees C. With a view towards the developm ent of continuous or semi-continuous flow biosorption processes it was decided to immobilize the material by (1) cross-linking with formalde hyde and (2) introducing that material into alginate matrices. Crossli nking the recovered biomass resulted in the formation of a biosorbent preparation with a maximum biosorption capacity of 185-190 mg/g dry we ight biomass at 15 degrees C. Following immobilization of biomass in a lginate matrices it was found that the total amount of uranium bound t o the matrix did not change with increasing amounts of biomass immobil ized. It was found however, that the proportion of uranium bound to th e biomass within the alginate-biomass matrix increased with increasing biomass concentration. Further analysis of these preparations demonst rated that the alginate-biomass matrix had a maximum biosorption capac ity of 220 mg uranium/g dry weight of the matrix, even at low concentr ations of biomass.