Biodegradation and kinetic analysis of phenol using low-density polyethylene immobilized Bacillus flexus GS1 IIT (BHU) in a packed bed bioreacto

Department of Chemical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi-221 005, Uttar Pradesh, India E-mail: bnrai.che@itbhu.ac.in Manuscript received online 07 December 2019, revised and accepted 03 January 2020 Phenol is considered as a precarious pollutant due to its carcinogenic, mutagenic nature even at low concentration. The present study emphasizes the degradation kinetics and behavior of a packed bed bioreactor (PBBR) for biodegradation of phenol using bacterial strain Bacillus flexus GS1 IIT (BHU). Low density polyethylene (LDPE) was used as packing material in a laboratory scale PBBR. Process variables such as pH, temperature were optimized and found to be 7.0 and 30ºC, respectively. Phenol biodegradation efficiency in PBBR was analyzed at optimum condition by varying substrate concentration between 25–700 mg/L. At optimum conditions, the maximum removal of phenol was observed to be 99.45% at 300 mg/L of initial phenol concentration. The kinetic constants were calculated from Monod and Andrew-Haldane model and found to be µmax: 0.215 h–1; Ks : 80 mg/L and µmax: 0.27 h–1; Ks : 66 mg/L; Ki : 300 mg/L, respectively