Influence of pH and natural organic matter on zinc biosorption in a model lignocellulosic biofuel biorefinery effluent.
The effect of dissolved natural organic matter (NOM) and pH on microbial biosorption of Zn was evaluated in a model lignocellulosic biofuel refinery effluent rich in NOM. Batch culture experiments conducted with two model microorganisms (yeast, Candida tropicalis; bacteria Novosphingobium nitrogenifigens Y88(T)), showed an inhibitory effect of NOM, and an optimum pH for Zn removal at 7.5-8.0. Membrane bioreactors with mixed autochthonous organisms were operated at pH 6.5 and pH 8.0 to better simulate real-world remediation scenarios. More Zn was removed at the high (91%) than at the low (26%) pH, presumably because the higher pH freed negatively-charged functional groups on the cellular biomass for passive Zn binding. Manipulating the pH of bioreactors can significantly improve metal removal in NOM rich wastewater. Such reactors could maintain water quality for closed-cycle biorefineries, leading to reduced water consumption, and a more sustainable biofuel.
Scion, 49 Sala Street, Rotorua 3010, New Zealand. Electronic address: amandajpalumbo@gmail.com.
Amanda J
AJ
Palumbo
Institute of Geological and Nuclear Sciences, PO Box 30-368, Lower Hutt 5040, New Zealand. Electronic address: C.Daughney@gns.cri.nz.
Christopher J
CJ
Daughney
Scion, 49 Sala Street, Rotorua 3010, New Zealand. Electronic address: Alison.Slade@scionresearch.com.
Alison H
AH
Slade
School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand. Electronic address: chris.glover@canterbury.ac.nz.
Chris N
CN
Glover
D000042:Absorption; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D056804:Biofuels; D018533:Biomass; D019149:Bioreactors; D041022:Candida tropicalis / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D008031:Lignin / Q000737:chemistry*; D009584:Nitrogen / Q000378:metabolism; D009930:Organic Chemicals / Q000737:chemistry*; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification / Q000379:methods*; D015032:Zinc / Q000737:chemistry*
D056804:Biofuels; D007220:Industrial Waste; D009930:Organic Chemicals; D014874:Water Pollutants, Chemical; C036909:lignocellulose; D008031:Lignin; D015032:Zinc; D009584:Nitrogen
Bioavailability; Bioremediation; Closed cycle mills; Heavy metals; Membrane bioreactors