Bioremediation of Halogenated Organics (PFAS), Aromatic Hydrocarbons, Radionuclides, and Ammonium

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Bioremediation of Halogenated Organics (PFAS), Aromatic Hydrocarbons, Radionuclides, and Ammonium

Princeton Dockets # 15-3080/2918-1, 18-3400-1, 19-3515-1, 19-3517-1

A novel anaerobic bioremediation system capable of:

1)       Energy efficient anaerobic ammonium removal, at lower temperature than Anammox

2)       Degrading wide range of organic pollutants, including halogenated organics, PFAS, PFOA, and aromatics to harmless intermediates.

3)       Trace metal/radionuclide immobilization, including U(VI) and potentially Se (IV).

Feammox Background, and Ammonia Removal

The bioremediation systems use Acidimicrobiaceae bacterium A6 (ATCC, PTA-122488) and conduct simultaneous ammonium oxidation and iron reduction under anaerobic conditions (Feammox). Proof of concept Feammox with A6 can achieve up to 90% ammonium removal in 20 days. The system is capable of operating as low as 15⁰C and can be energetically competitive against the Anammox process. A6 is an electrode-reducing bacterium and can operate iron-free in specially designed bioelectrochemical reactors. Thus, the system is a candidate for scale up for ammonia removal (without iron) or for large scale biomass production.

Organic Pollutant Treatment

PFAS are ubiquitous, stable, slow and very difficult to degrade. If they degrade at all, they form fluorinated intermediates which are more toxic. A6 Feammox has been shown to degrade and to potentially mineralize a variety of PFAS. To date, heptafluorobutyric acid, perfluorooctanoic acid PFOA, 2,2,2,-trifluoroethyl nonafluorobutanesulfonate were defluorinated at 55% and HFBA was defluorinated 30% during a 2 week incubation period. A6 Feammox is also capable of treating a wide range of recalcitrant organic contaminates including halogenated and aromatic compounds such as TCE, PCE, benzene, phenanthrene, quinolone, ethylene dibromide, and potentially more

Trace Metal/Radionuclide Immobilization

The A6 Feammox process can treat a variety of inorganics because the iron reduction pathway is non-specific. As a proof of concept, the team has reduced U(VI) to insoluble U(V), Cu(II) to insoluble Cu(I). Work on selenium immobilization is ongoing.



       Environmental remediation: soil, ground water, waste water, chemical remediation

       Ammonium removal

       Organic contaminant treatment

       Trace metal/radionuclide immobilization


       Degrade PFAS by defluorination to non-toxic intermediates

       Low cost (anaerobic, room temperature process)

       Electrogenic (electrode-reducing bacterium): Can be engineered to operate iron free

       Potentially scalable

       Applicable to wide range of pollutants


Intellectual Property & Development Status

United States Patent #9,815,723 on “Methods and Compositions for Nitrogen Removal Using Feammox Microorganisms” has been granted on Nov. 14, 2017.

Additional patent applications have been filed regarding composition and methods to significantly improve the contamination removal rate as claimed in this non confidential brief (up to 90% removal in 20 days), to remove halogenated organics including PFAS, and for bioelectrochemical systems.

Prof. Jaffe is seeking industrial partners for co-development to:

1)       Validate method effectiveness for implementation in practical environments

2)       Scale up assessment and development, including co-development of microbial electrolysis cell (for scale up

3)       Evaluate additional pollutants of interest

4)       Remediation situations and customers with naturally high Fe content


Additional publications are pending.

Ge, J. et al., “Degradation of Tetra- and Trichloroethylene under Iron Reducing Conditions by Acidimicrobiaceae sp. A6,” 2018 in review.

Ruiz, M., et al., “Oxidation of Ammonium by Feammox Acidimicrobiaceae sp. A6 in Microbial Electrolysis Cells,” 2018, in review.

Ruiz, M., et al., “Electrode Colonization by the Feammox Bacterium Acidimicrobiaceae sp. A6,” Applied and Environmental Microbiology, 2018 in press, DOI: 10.1128/AEM.02029-18,

Huang, S., and Jaffe, P.R., “Isolation and Characterization of an Ammonium-Oxidizing Iron reducer: Acidimicrobiaceae sp. A6,” PLoS ONE, 2018, 13(4).

Huang, S., et al., “Environmental Factors Affecting the Presence of Acidimicrobiaceae and Ammonium Removal under Iron-reducing Conditions in Soil Environments,” Soil Biology and Biochemistry, 2016, Vol. 98, pp. 148-158, doi: 10.1016/j.soilbio.2016.04.012.

Gilson, E.R., et al., “Biological Reduction of Uranium by Acidimicrobiaceae bacterium A6,” Biodegradation, 2015, Volume 26, Issue 6, pp. 475-482, doi: 10.1007/s10532-015-9749-y.

Huang, S. and P.R. Jaffe, “Characterization of incubation experiments and development of an enrichment culture capable of ammonium oxidation under iron-reducing conditions,” Biogeosciences, 2015, 12, 769-779, doi: 10.5194/bg-12-769-2015.

The Inventors

Prof. Peter Jaffe is a Professor of Civil and Environmental Engineering and the Associate Director for Research of the Andlinger Center for Energy and the Environment. For “Application of Feammox Process in Wastewater Treatment,” Prof. Jaffe received Excellent International Cooperation Project Award from the Guangzhou Association of Industrial Environmental Protection in 2017. He has served on numerous committees and panels, including the National Research Council, EPA, NIH, NSF, DOE and was elected Fellow of the American Geophysical Union in 2012. The research interests of the Jaffe laboratory relate to the physical, chemical, and biological processes that govern the transport and transformation of pollutants in the environment and their application towards the remediation of contaminated systems.  Areas of current emphasis include laboratory and field experiments, as well as mathematical simulations of biogeochemical processes in porous media, such as:  (1) numerical simulation of denitrification in soils as a function of rainfall and soil properties, and the scaling of these results to link them to climate change models; (2) biogeochemically mediated dynamics of trace metals in sediments, wetland soils, and groundwater; (3) biological reduction of uranium in groundwater and the long-term stability of the reduced uranium phases; (4) nitrogen processing in urban settings coupled to urban hydrology; and (5) effects of carbon dioxide sequestration in deep aquifers on shallow soils due to potential leaks.

Dr. Shan Huang is an Associate Research Scholar in the Department of Civil and Environmental Engineering at Princeton University. Her research focus is ammonium oxidation in oxygen limited wetland environments, using Ferric Iron as an electron acceptor. Shan received her Ph.D. in Environmental Biotechnology from Sun Yat-Sen University, China in 2011. Shan has worked on denitrification functional genes in estuarine sediments and ANAMMOX treatment of ammonium-rich wastewater during her PhD and published a number of research papers on these subjects.



Linda Jan

Princeton University Office of Technology Licensing • (609) 258-3653 •

Laurie Tzodikov

Princeton University Office of Technology Licensing • (609) 258-7256 •


Patent Information:
For Information, Contact:
Prabhpreet Gill
Licensing Associate
Princeton University
Peter Jaffe
Shan Huang
Emily Gilson
civil engineering
metal reduction
wastewater management