Biodegradation Of Phenol Using Bacillus Cereus Wj1 And Evaluation Of Degradation Efficiency Based On A Graphene-Modified Electrode

A bacterial strain was isolated from the phenol-contaminated wastewater, and was identified as a member of Bacillus cereus based on standard morphological, biochemical characteristics and 16S rDNA sequence analysis. The strain exhibited optimum phenol degradation performance with the addition of 100 mg/L glucose at pH 7.0, 30 degrees C. Haldane's model could be fitted to the growth kinetics data well over a range of initial phenol concentrations (50-600 mg/L), with kinetic values maximum specific growth rates mu(max) = 0.153 h(-1), half saturation coefficient K-s = 21.33 mg/L and substrate inhibition coefficient K-i = 238 mg/L. The concentration of phenol was determined using differential pulse voltammetry (DPV) at graphene (GR)-modified glassy carbon electrode (GCE) in the presence of cetyltrimethylammonium bromide (CTAB). Under the optimized conditions, the oxidation peak current of phenol was linear over a concentration range from 0.05 to 100 mg/L with the detection limit (S/N = 3) of 0.02 mg/L. This method combined phenol biodegradation with electrochemical determination, and the results were satisfactory.