Simultaneous removal of p-cresol and methylene blue dye through upward-flow packed bed biofilm reactor (UFPBBR): Kinetics, phytotoxicity and bacterial toxicity assessment

Abstract

An Upward-Flow Packed Bed Biofilm Reactor (UFPBBR) was used for the simultaneous removal of p-cresol and methylene blue dye from wastewater. Maximum specific growth for p-cresol (100 mg L−1) and Methylene blue dye (MBD) (50 mg L−1) was found to be 0.21 ± 0.0083 h−1 and 0.05 ± 0.0028 h−1, respectively. Three independent parameters, such as contact time, pH, and effect of sodium acetate (g/100 mL), were optimized. The maximum removal of p-cresol, MBD, and Total organic carbon (TOC) were found to be 91.69 ± 2.13 %, 95 ± 1.58 %, and 82.28 ± 1.24 %, respectively. The biodegradation rates were analyzed using various kinetic models. First-order kinetic followed for both p-cresol and MBD degradation with a rate constant of 0.55 day−1 and 0.50 day−1, respectively. The maximum % RE and ECp were found to be 97.23 %, 1400.112 mg L−1 day −1 for p-cresol and 98.41 %, 687.61 mg L-1 day-1 for MBD, respectively. Phytotoxicity and bacterial toxicity assessments were evaluated to explore the possibility of treated wastewater in green belt development and other applications. © 2024 Elsevier Ltd