Biotreatment of Waste Water Containing Oil Soluble Azo Dye

Due to the lack of detailed studies of bacterial decolorization of oil soluble azo dyes, the necessarily for this issue is highly felt. This research is carried out to investigate the potential of a salt tolerant bacterium, to degrade Toluidine Red (TR) as an oil soluble azo dye. Effect of environmental parameters (independent variables) on decolorization efficiency was optimized using the stepwise strategy named one factor at a time (OFAT) method. According to the results, the optimal conditions were: 25 ppm dye as sole carbon and energy source, pH 6.5, NaCl 5-7.5% (w/v) and temperature 35°C. 0.25% (v/v) of Tween 80 was used in preparation of dye stock solution due to the insolubility ofazo dye in water. Analytical methods confirmed degradation mechanism under which color removal was occurred. Findings demonstrated that Halomonas strain Gb could be a potential candidate for treatment of industrial waste water containing oil soluble azo dyes under high-salinity conditions.

Keywords:

Azo dye , Decolorization , Oil soluble , HPLC