Research on adsorption of cationic dyes by waste brewer´s yeast

The potential of waste brewer´s yeast(WBY) used as bio-adsorbent to adsorb BasicGreen(BG) was investigated in this paper. Adsorption of BG was pH-dependent and the optimum pH for cation dye is 5.0 . Kinetic process of Basic Green adsorbed by waste brewery´s yeast can well described by pseudo-second-order models. With the increase of initial dye concentration, the adsorption quantity increased and the adsorption percentages of the dyes decreased . The higher the initial concentration was, the longer the time required to reach adsorption equilibrium was.The higher the temperature was, the greater the adsorption on dye by WBY was and the adsorption is also easier to carry out. To the dyes, the isothermal data of adsorption followed both the Langmuir and Freundlich models ,but much better to the Freundlich models. Amino, amide, carboxyl, phosphate groups are responsible for the dye adsorbed by waste brewery´s yeast. The results in this study indicated that WBY was a good cationic dye sorbent and a low cost biomaterial for dye wastewater treatment.lt is feasible to use WBY to adsorp cationic dye wastewater.