Abstract:

A new biosorbent from waste beer yeast was prepared by modification with triethylenetetramine and crosslinking with glutaraldehyde. The adsorption capability of the modified yeast for Hg(Ⅱ) in aqueous solution and the influence factors were studied. The results show that the optimized pH value was 2.8 at 25 ℃ and the adsorption process was carried out for 20 min. The maximum uptake capacities for Hg(Ⅱ) is 132.6 mg/g, which is about 6.3 times higher than that of the pristine yeast. With the modified yeast, the average removal rate for Hg(Ⅱ) in the wastewater is 100%. The kinetics for Hg(Ⅱ) adsorption followed the pseudo-second-order with R2=0.999 9. The adsorption process fitted the Langmuir model, indicating that it is a monolayer adsorption process.

Key words: triethylenetetramine, beer’s waste yeast, modify, adsorption, Hg(Ⅱ)