Fungal elimination of toluene vapor in one- and two-liquid phase biotrickling filters: Effects of inlet concentration, operating temperature, and peroxidase enzyme activity.
In this study, performance of biotrickling filters (BTFs) inoculated with fungus Phanerochaete chrysosporium at 30 °C and 40 °C in the absence and presence of silicone oil (10% v/v) was investigated. Removal of toluene was carried out at empty bed residence time (EBRT) of 1 min and at inlet concentrations of 0.5-4.4 g m-3 and 0.5-24.7 g m-3 for one-liquid phase (OLP-BTF) and two-liquid phase BTF (TLP-BTF), respectively. In general, at 40 °C, removal efficiencies (REs) > 80% were obtained in OLP-BTF for the inlet toluene concentrations < 2.5 g m-3, and REs > 70% were obtained for concentrations < 18 g m-3 in TLP-BTF. Based on the balanced equation for biodegradation, fungal respiration produced more CO2 in OLP-BTF (1.38 mol CO2/mole toluene) in comparison to TLP-BTF (0.67 mol CO2/mole toluene). In other words, the presence of oil enhanced microbial growth due to the increase of hydrophobic substrate bioavailability. The activity of extracellular ligninolytic manganese peroxidase (MnP) enzyme produced by the fungal culture was detected in the range of 27.6-71.6 U L-1 (μmol min-1 L-1) at 40 °C in TLP-BTF, while no enzymatic activity was detected in OLP-BTF.
['Yousefinejad|Ali|A|', 'Zamir|Seyed Morteza|SM|', 'Nosrati|Mohsen|M|']
D000393:Air Pollutants D061006:Bays D001673:Biodegradation, Environmental D019149:Bioreactors D005374:Filtration D005658:Fungi D009195:Peroxidase D010544:Peroxidases D013696:Temperature D014050:Toluene
Enzymatic activity Biofilm CO(2) production rate Ligninolytic enzyme Mass transfer limitation T-test