PMID- 12767298 OWN - NLM STAT- MEDLINE DCOM- 20031210 LR - 20131121 IS - 0043-1354 (Print) IS - 0043-1354 (Linking) VI - 37 IP - 12 DP - 2003 Jul TI - Continuous biotransformation and removal of nitrophenols under denitrifying conditions. PG - 2953-9 AB - The effect of COD/NO(3)(-)-N ratio on the biotransformation and removal of 2-nitrophenol (2-NP), 4-nitrophenol (4-NP), and 2,4-dinitrophenol (2,4-DNP) was studied in bench scale upflow anaerobic sludge blanket (UASB) reactors. Sodium acetate and sodium nitrate were used as electron donor (substrate) and electron acceptor, respectively. Nitrate nitrogen loading was increased from 0.098 to 0.6 kg/m(3)d in order to keep COD/NO(3)(-)-N ratio as 20.8, 14.3, 9.8, 5.0, 4.0 and 3.33. Throughout the study, input nitrophenolic concentration and hydraulic retention time (HRT) were kept constant as 30 mg/l and 24h, respectively. 2-Aminophenol (2-AP), 4-aminophenol (4-AP) and 2-amino,4-nitrophenol (2-A,4-NP) were found as the major intermediate metabolite of 2-NP, 4-NP and 2,4-DNP, respectively. Removal of all the three nitrophenols increased with lowering of COD/NO(3)(-)-N ratio. However, nitrophenols removal got adversely affected when COD/NO(3)(-)-N ratio was reduced below 5. Maximum removal achieved were 91.63%, 90.17% and 86.10% for 2-NP, 4-NP and 2,4-DNP, respectively at a COD/NO(3)(-)-N ratio of 5. Simultaneous denitrification and methanogenesis was observed in all the reactors throughout the study. FAU - Karim, Khursheed AU - Karim K AD - Centre for Environmental Science and Engineering, Indian Institute of Technology, Powai, Mumbai 400 076 , India. FAU - Gupta, S K AU - Gupta SK LA - eng PT - Journal Article PL - England TA - Water Res JT - Water research JID - 0105072 RN - 0 (Nitrophenols) RN - 0 (Water Pollutants, Chemical) RN - N762921K75 (Nitrogen) RN - OP0UW79H66 (Methane) SB - IM MH - Bioreactors MH - Biotransformation MH - Methane/analysis MH - Nitrogen/chemistry MH - Nitrophenols/*metabolism MH - Water Pollutants, Chemical/*metabolism MH - *Water Purification EDAT- 2003/05/28 05:00 MHDA- 2003/12/12 05:00 CRDT- 2003/05/28 05:00 PHST- 2003/05/28 05:00 [pubmed] PHST- 2003/12/12 05:00 [medline] PHST- 2003/05/28 05:00 [entrez] AID - S0043-1354(03)00073-3 [pii] AID - 10.1016/S0043-1354(03)00073-3 [doi] PST - ppublish SO - Water Res. 2003 Jul;37(12):2953-9. doi: 10.1016/S0043-1354(03)00073-3.