Biosorption of thallium by dry biofilm biomass collected from a eutrophic lake

Thallium poisoning due to thallium-bearing ore exploitation is very grave in sonic mining areas in Guizhou China. However, effective treatment technologies for Tl-containing wastewater were unavailable. The study showed that dead eutrophic biofilm biomass was effective in removing Tl from aqueous solution when the solution was basic. The adsorption process is rapid and equilibrium was approached at about 30 min. The pseudo-second order equation was applicable to all the kinetic data. The Langmuir Isotherm Model could be used to fit Tl sorption data well over a concentration range 10-1000 ug/l. The adsorption capacity was about 332.23 ug/g dry biomass. The adsorption column containing 2.5 g of dry biomass could purify 2000 ml of 500 ug/l Tl solution before breakthrough.