Biosorption of the Industrial Dye Remazol Brilliant Blue R by Bacillus rigiliprofundi

Remazol Brilliant Blue R (RBBR), a common precursor of other dyes and a toxic organo-pollutant, is an anthraquinone dye extensively used in the textile industry. In this study, biosorption of RBBR by the bacterial strain Bacillus rigiliprofundi was investigated. The effects of various physical parameters on dye adsorption were studied. The kinetics and isotherm of adsorption were analyzed. The bacterial adsorbent was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Phytotoxicity was evaluated before and after adsorptive removal of the dye. Up to 80% RBBR was adsorbed and removed by the bacteria in ten days. The optimum conditions for biosorption were pH 5.5, adsorbent dosage 30 mg, initial dye concentration 25 mg/L, and temperature 40 degrees C. Adsorption followed the pseudo-first order kinetics and fitted appropriately to the Langmuir model. This is the first report on adsorptive decolorization of the highly recalcitrant RBBR by the strain Bacillus rigiliprofundi.