Studies on biodecolorization of cibacron reactive dyes

Abstract

In this modern world, the demand for a wide variety of textile fabrics and garments is consistently increasing, which in turn increases the establishment of textile dyeing and processing industries. Textile dyeing and processing industries use a variety of synthetic dyestuffs such as acid, base, vat, sulphur, indigo, azo and reactive dyes depending on the nature of the fabric and the intensity of color required. A lot of work has been done and reported in the literature for decolorization of azo reactive dyes, but only few researches have been reported regarding the decolorization of Cibacron azo reactive dyes. In addition their work is limited to optimization of operating variables such as selection of microorganism, pH etc. In order to develop any reactor, configuration for continuous decolorization of effluent requires process reaction kinetics. Since quantitative information of process kinetics is limited, the present research involves a detailed study which has been carried out to develop a kinetic model for decolorization of textile effluents. From the decolorization studies carried out under optimized process conditions, it was observed that the Cibacron dyes underwent maximum decolorization by free cells of mixed bacterial consortium when compared to other individual cultures. The decolorization of Cibacron dyes was found to follow Michaelis-Menten kinetics. It was observed that the decolorization rate was higher when mixed bacterial consortium was used. Hence from the above study, it was observed that both bacteria and fungi have the potential ability to decolorize the Cibacron dyes. It was also found in both the cases that the mixed cultures produced better results. The fungi were able to produce higher decolorization rates than bacteria. Hence it is suggested that the textile effluents containing Cibacron dyes can be biodegraded sequentially using bacteria and then fungi so as to achieve maximum decolorization of the dyes. newline