title: [Biodegradation of pyridine under UV irradiation].
abstract: Pyridine, a complex nitrogen-containing heterocyclic compounds, is usually difficult to degrade by means of single biological method. The internal loop photobiodegradation reactor (ILPBR) was used for degradation of pyridine in batch and continuous experiments following three protocols: photolysis alone (P), biodegradation alone (B), and intimately coupled photolysis and biodegradation (P&B) to investigate the regularity of pyridine degradation. The experimental results indicated that pyridine removal rate by P&B was fastest among three protocols in batch experiment, in which protocol B was faster than P. For initial pyridine concentration of 100 mg L(-1), the pyridine removal rates were respectively 4.95, 10.2 and 14.58 mg (L x h)(-1) corresponding to protocol P, B and P&B. Pyridine degradation kinetic equations were established based on Monod model, and the saturation constants decreased from 1920.4 mg x L(-1) for protocol B to 1094.1 mg x L(-1) for protocol P&B. Protocols P, B and P&B were also used for pyridine degradation in continuous flow and influent pyridine concentration increased from 50 to 300 mg x L(-1), and their average removal rates were respectively 15.8 mg (L x h)(-1) for protocol P, 23.1 mg x (L x h)(-1) for protocol B and 24.9 mg x (L x h)(-1) for protocol P&B, in which the removal rates were higher than that in batch. Experiments suggested that the inhibition of pyridine to biofilm could be relieved due to UV irradiation in process of intimately coupled UV photolysis and biodegradation, and biofilm had kept its bioactivity degrading pyridine and enhanced pyridine removal rates.
authors.affiliation: Department of Environmental Engineering, School of Life and Environmental Science, Shanghai Normal University, Shanghai 200234, China. fmm870425@126.com
authors.forename: Miao-Miao
authors.initials: MM
authors.lastname: Fang
authors.forename: Ning
authors.initials: N
authors.lastname: Yan
authors.forename: Yong-Ming
authors.initials: YM
authors.lastname: Zhang
mesh_terms: D001419:Bacteria / Q000378:metabolism / Q000528:radiation effects; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000528:radiation effects*; D019149:Bioreactors / Q000382:microbiology*; D010782:Photolysis / Q000528:radiation effects; D011725:Pyridines / Q000302:isolation & purification* / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D011725:Pyridines; D062065:Wastewater; C023666:pyridine