Abstract:

Two decolorizing bacteria were isolated from activated sludge, and J-H mixed bacteria were synthesized by comparative ex-periments to degrade malachite green and analyze its kinetic characteristics. The influence of different reaction conditions on dye decol-orization was studied. The degradation products of mixed bacteria were analyzed by UV-Vis absorption spectrum and GC-MS, and theadvantages of mixed bacteria in treating malachite green and the mechanism of synergistic degradation were revealed. The results showed that under the condition of facultative oxygen, pH 7. 0 and 30 ℃ , the decolorization rate of mixed flora to malachite green withconcentration of 50 mg / L was close to 100%, and the complete decolorization time of mixed flora was more than 5 times faster than thatof pure strain, and the reaction process was in accordance with the secondary reaction kinetics process. Decolorization efficiency ofmixed flora on malachite green was affected by oxygen supply conditions, dye concentration, pH and temperature, and the degradationproducts of malachite green by mixed flora were mainly 4-( dimethylamino) benzophenone and 4-( dimethylamino) phenol. These re-sults confirmed that the mixed flora can be used as a highly efficient microorganism for the degradation of malachite green.

Key words: decolorizing strains, mixed flora, synergistic degradation, malachite green, degradation pathways