Feasibility of different carbon sources for growing microbial biomass in aerobic batch reactor and their application for dye removal from contaminated wastewater

Abstract

In search for a cheaper energy source, this study was undertaken to investigate the potential of mixed culture for the decolorization of Methylene blue (MB) and Remazol black B (RBB) using glucose, molasses, and cheese whey as an energy source for microbial growth in aerobic batch reactor. The experiments were performed with synthetic solutions of both the dyes ranging from 25 to 300 mg l−1. The results show that the decolorization and microbial growth was affected by the increase in concentration of dyes leading to the decreased decolorization of dyes. The presence of glucose was found to be more efficient as compared to molasses and cheese whey. After 36 h, mixed culture was able to decolorize MB up to 83, 59, and 54% and RBB up to 80, 58, and 52% in the presence of glucose, molasses, and cheese whey, respectively, at 300 mg l−1 initial dye concentration. The maximum specific uptake was 57, 51, and 52 mg g−1 in presence of glucose, molasses, and cheese whey, respectively, at 300 mg l−1 initial dye concentration of RBB. The maximum specific uptake was 58, 51, and 53 mg g−1 in the presence of glucose, molasses, and cheese whey, respectively, at 300 mg l−1 initial dye concentration of MB. The results of this study shall be useful to develop a suitable decolorization process for the treatment of dye-contaminated wastewater or wastewater contaminated with a variety of dyes.