title: Simultaneous ammonium-nitrogen and copper removal, and copper recovery using nitrifying biofilm from the ultra-compact biofilm reactor.
abstract: Simultaneous ammonium-nitrogen (NH(4)(+)-N) and copper removal, and copper recovery in synthetic wastewater using nitrifying biofilm from an ultra-compact biofilm reactor (UCBR) was demonstrated in batch studies, which consisted of three phases: Phase 1 for NH(4)(+)-N and copper removals, Phase 2 for copper recovery, and Phase 3 for NH(4)(+)-N removal. The results showed that more than 96.3% of copper was removed within 60min, while 60.1% of the adsorbed copper was recovered through rinsing the biofilms with 0.1mM of ethylenediaminetetraacetic acid (EDTA). The nitrifying biofilm was able to adsorb 0.245mg of copper/g of biofilms. After recovery treatment, 29.4% of copper remained bound within the nitrifying biofilms. No significant inhibitory effects towards NH(4)(+)-N removal in the presence of 0.92mg copper/L was noted in Phase 1 compared with the control test. However, lower initial pH condition in the recovery process and the accumulation of copper on the biofilm led to 50% inhibition on NH(4)(+)-N removal efficiency in the subsequent phase.
authors.affiliation: Division of Environmental Science and Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore.
authors.forename: L Y
authors.initials: LY
authors.lastname: Lee
authors.forename: S L
authors.initials: SL
authors.lastname: Ong
authors.forename: H Y
authors.initials: HY
authors.lastname: Ng
authors.forename: J Y
authors.initials: JY
authors.lastname: Hu
authors.forename: Y N
authors.initials: YN
authors.lastname: Koh
mesh_terms: D000327:Adsorption; D018441:Biofilms; D019149:Bioreactors; D003300:Copper / Q000302:isolation & purification*; D004492:Edetic Acid / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000302:isolation & purification*; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification*
chemical_list: D000644:Quaternary Ammonium Compounds; D003300:Copper; D004492:Edetic Acid; D009584:Nitrogen