title: Biodegradation of tetramethylammonium hydroxide (TMAH) in completely autotrophic nitrogen removal over nitrite (CANON) process.
abstract: This study conducted a completely autotrophic nitrogen removal over nitrite (CANON) process in a continuous anoxic upflow bioreactor to treat synthetic wastewater with TMAH (tetramethylammonium hydroxide) ranging from 200 to 1000mg/L. The intermediates were analyzed for understanding the metabolic pathway of TMAH biodegradation in CANON process. In addition, (15)N-labeled TMAH was used as the substrate in a batch anoxic bioreactor to confirm that TMAH was converted to nitrogen gas in CANON process. The results indicated that TMAH was almost completely biodegraded in CANON system at different influent TMAH concentrations of 200, 500, and 1000mg/L. The average removal efficiencies of total nitrogen were higher than 90% during the experiments. Trimethylamine (TMA) and methylamine (MA) were found to be the main biodegradation intermediates of TMAH in CANON process. The production of nitrogen gas with (15)N-labeled during the batch anaerobic bioreactor indicated that CANON process successfully converted TMAH into nitrogen gas.
authors.affiliation: Department of Safety, Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, 2 Jhuoyue Road, Nanzih, Kaohsiung 811, Taiwan.
authors.forename: Shen-Yi
authors.initials: SY
authors.lastname: Chen
authors.affiliation: Institute of Environmental Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan.
authors.forename: Li-An
authors.initials: LA
authors.lastname: Lu
authors.affiliation: Institute of Environmental Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan. Electronic address: jglin@mail.nctu.edu.tw.
authors.forename: Jih-Gaw
authors.initials: JG
authors.lastname: Lin
mesh_terms: D000468:Alkalies / Q000032:analysis; D052818:Autotrophic Processes; D061249:Batch Cell Culture Techniques; D001673:Biodegradation, Environmental; D019149:Bioreactors; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D009573:Nitrites / Q000378:metabolism*; D009584:Nitrogen / Q000302:isolation & purification*; D009587:Nitrogen Isotopes; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012212:Rheology; D014865:Waste Disposal, Fluid; D062065:Wastewater
chemical_list: D000468:Alkalies; D009573:Nitrites; D009584:Nitrogen; D009587:Nitrogen Isotopes; D000644:Quaternary Ammonium Compounds; D062065:Wastewater; C027917:tetramethylammonium
keywords: Anoxic upflow reactor; CANON process; Tetramethylammonium hydroxide (TMAH)