Cadmium biosorption by baker’s yeast in aqueous suspension

Abstract

The biosorption of cadmium from artificial aqueous solutions using native baker’s yeast was investigated. The highest metal uptake value was 110 mg g-1 in a suspension of 0.3 g L-1. The effect of pH, initial cadmium concentration, adsorption time and biosorbent dosage on biosorption by baker’s yeast was studied. The maximum biosorption capacity of cadmium by yeast was observed at pH 6.0. The adsorption equilibrium was reached within sixty minutes and the sorption process followed pseudo second-order kinetics. Cadmium biosorption isotherms were determined in the cadmium concentration range of 10-500 mg L-1 at pH 6 in a suspension of 0.3 g L-1. For evaluation of biosorption equilibrium Langmuir and Freundlich equations were applied to the experimental data.

Keywords

• cadmium
• baker’s yeast
• biosorption
• pH
• kinetics
• isotherm
• biosorbent dosage