Application of Response Surface Methodology for Removal of Remazol Yellow (RR) by Immobilised S. cerevisiae on Pumice Stone

In this study, Remazol Yellow (RR) removal was investigated by Saccharomyces cerevisiae immobilized on pumice stone. For the immobilization process, a new technic was used and immobilization matrix HCl pretreated pumice stone was added to the growth medium of microorganism. pH, initial biosorbent (Co), and dye concentration (Cb) effect on biosorption were optimized through the Response Surface Methodology (RSM) and the second-order quadratic model was used to describe the effects of parameters successfully. At optimum conditions pH 3, Cb 2.5 g/L, C0 400 ppm maximum dye removal was 99%, and 140 mg/g capacity was cached. When pumice stone, HCl treated pumice stone and Saccharomyces cerevisiae were used in biosorption experiments directly 44%, 69%, 75% dye removal was obtained respectively. 0.5 M NaOH (pH 13.69) and water (pH 8) were chosen as a desorption agent for the immobilized biosorbent. Desorption efficiency was found 21% with 0.5 M NaOH and 1.5% with water (pH 8). The characterization studies were performed by using Scanning Electron Microscope (SEM) and Fourier Transformer InfraRed (FT-IR) spectroscopy. The results indicate that immobilized biosorbent is a promising alternative for the biosorption of Remazol Yellow (RR) from aqueous solutions.