Decolorisation and degradation of reactive black 5 (RB5) dye by coImmobilized dye degrading microbe with spent coffee ground biochar

Water pollution is the most threatening pollution to biodiversity especially the aquatic life. One of the source of water pollution comes from the disposal of effluents from dyebased industries such as textile industry. The colorant from dyestuff interfere the aquatic ecosystem by lowering light penetration, gas solubility and interference in phytoplankton’s photosynthesis. Azo dye is highly toxic as it possesses electron withdrawing nature, which later develops en electron deficiency and become reduced to carcinogenic amino compound. The main purpose of this study is to immobilize dye degrading microbe, UMKDG-1, on spent coffee ground biochar and to analyze the decolorisation and degradation of Reactive Black 5 dye by the immobilized dye degrading microbe. All the decolorisation assay were carried out in batch using 0.1% and 0.01% (w/v) Reactive Black 5, pH8 and incubated at 30°C under static condition. The control for this experiment are Reactive Black 5 dye powder, alginate beads, biochar beads and microbial beads. Decolorisation efficiency on different initial dye concentration (0.1% and 0.01%, w/v) was determined. It was found that higher decolorisation rate was recorded for decolorisation assay of 0.01% (w/v) Reactive Black 5 (30.32%). However, unsuitable FTIR analysis method was used which resulted in the same spectra formation when compared to control, lead to inaccurate determination of the degraded metabolites