摘要：In the present study the biosorption of Reactive Red 239, Reactive Yellow 3RS and Reactive Blue 194 by Simplicillium obclavatum were investigated with 5% NaCl addition. The effects of pH of solution, biosorption temperature and initial dye concentration on dye removal were determined. pH 1, 270 min of contact time and 303 K were more favorable for biosorption. In kinetic studies, pseudo-second-order model fitted better than pseudo-first-order model. Maximum biosorption was observed in acidic conditions, which reveals a typical chemisorption was the primary mechanism in the studies. Various isotherm models were employed to understand the biosorption process. The Langmuir isotherm model showed all the better fit than the Freundlich model in high-salt and non-salt solution. There was a little increase of the maximum biosorption capacity (q~(max)) of RR239, RY3RS and RB194 predicted by Langmuir isotherm data in non-salt solution compare with that in high-salt solutions. The reduction of q~(max) might be due to competing adsorption sites between dye molecule and chlorine ion. Scanning electron microscopy images showed the morphologies of Simplicillium obclavatum were normal in high-salt solutions and addition of 5% NaCl had little effect on the biosorption of dyes. FT-IR analysis revealed the amine groups existed as the major adsorbent sites for the anionic dyes.
关键词：Anionic industrial dye;Simplicillium obclavatum;biosorption;isotherm;kinetics;morphology;high salt solution
