Study of the biosorption of phenol by the cell walls of brewing yeast

Abstract

Sorption capabilities of cell walls of yeast Saccharomyces cerevisiae with respect to phenol have been investigated. Elemental analysis established the composition of yeast cell walls: 47.8–48.6% C; 5.7-6.1% N and 6.86% H. The surface of the sorbent determined by BET, was 118.6 m2/g, ash content – 18-22%. Using FTIR-spectroscopy, it is shown that the prevailing mechanism of phenol adsorption is physical sorption, and not complexation. The adsorption abilities of yeast cell walls with respect to phenol were studied relative to pH, initial phenol concentration, sorbent dose and activation time. It is shown that the sorption efficiency increases in protonated solutions with pH<3. Experimental data were analyzed using Freundlich and Langmuir models. The model of the adsorption isotherm is more precisely described by the Langmuir equation with R2 0.9987. The calculated maximum capacity is 18.9 mg of phenol per 1 g of dry sorbent. The study showed that the cell walls of the yeast Saccharomyces cerevisiae can be used as a new adsorption material for eliminating phenol from aqueous solutions.

Keywords

• phenol
• biosorption
• cell walls of yeast saccharomyces cerevisiae
• adsorption isotherms
• ftir spectroscopy