CAES: Joseph J. Pignatello

Joseph J. Pignatello


{Joseph Pignatello}

Department of Environmental Sciences
The Connecticut Agricultural Experiment Station
123 Huntington Street
P.O. Box 1106
New Haven, CT 06504
Voice: (203) 974-8518 Fax:(203) 974-8502

Dr. Pignatello has expertise in physical organic chemistry; soil chemistry; environmental chemistry and engineering; fate of organic compounds in the environment; and water and soil treatment processes.

B.A., Chemistry, University of Minnesota, Minneapolis
Ph.D., Chemistry, University of California, Berkeley

Station career:
Assistant Scientist II, 1984-1988
Associate Scientist, 1988-1993
Scientist, 1993-2004
Senior Scientist, 2004-2013
Chief Scientist, 2013-present

Past research:
Biodegradation of fumigants in soil and groundwater. Solvent extraction techniques for determining volatile organic compound and pesticide concentrations in soil. Field and laboratory studies to determine the causes of sequestration of pesticides and other chemicals in soil. Mechanistic modeling of sorption by soil organic matter. Rates of sorption and desorption in soil. Advanced oxidation process (especially the Fenton reaction) for degrading pesticides and many other types of compounds in soil and water.

Present research:
In general terms, the group’s research interests include interactions of organic compounds with soils and sediments, remediation of contaminated water and soil, and sunlight-driven reactions in the environment. Its research covers both fundamental and applied aspects of these areas, and deals with a diversity of compounds within the categories of legacy pollutants, emerging pollutants such as endocrine disrupting compounds and pharmaceuticals, and nanomaterials. The group uses a variety of physical and chemical techniques, such as gas and liquid chromatography, solid and liquid state NMR spectroscopy, high resolution gas adsorption, diffuse-reflectance FTIR and UV/visible spectroscopies, XRD, HRTEM, SEM, AFM, thermomechanical and thermogravimetric analyses, radioisotope techniques, and computational molecular modeling.

Many of the projects are collaborative with individuals at CAES, Federal research laboratories, American and foreign universities, and private industry. In addition to my position at CAES, I also hold the position of Professor Adjunct of Chemical and Environmental Engineering at Yale University

Below is a brief description of current projects in the group.

  • Adsorption of ionic and ionogenic compounds by pyrogenic carbonaceous materials. The group is investigating novel interactions of ionic and ionogenic compounds on surfaces of graphite, graphene, biochar, carbon nanotubes and activated carbon, including, i) formation of exceptionally strong hydrogen bonds by weak acids (e.g., carboxylic acids, phenols, sulfonamides); ii) p-p electron donor-acceptor interactions between charged aromatic amines and the polyaromatic surfaces. These reactions are identified and quantified using classical isotherm analysis, competitive and synergistic effects of multiple adsorbates, spectroscopic techniques, kinetic isotope effects, and others.
  • Nanoscale interactions between engineered nanomaterials and black carbon. Engineered nanomaterials enter agricultural soils as ingredients of pesticide formulations and via application of municipal solid waste. My group is investigating the strength and reversibility of heteroaggregation and pore network penetration of carbon- and metal-based engineered nanoparticles with char particles. Collaborators with the group are determining the bioavailability of nanomaterials towards earthworms and certain crop plants in the presence of biochar. (Collaboration with USDA-ARS and Dr. Jason White at CAES).
  • Impact of halide ions on sunlight-driven photolysis of organic pollutants and dissolved organic matter in marine and estuarine waters. Apart from manifesting ionic strength effects, halide ions—especially Br and I—can interact with secondary oxidants such as hydroxyl radical, hydroperoxyl radical and ozone, as well as organic triplet excited states, to generate reactive halogen species, X×, X2-×, HOX, X2 and X3-. These RHS, in turn, can oxidize and/or halogenate organic compounds. We are investigating the significance, kinetics, and mechanisms of these reactions with respect to both dissolved natural organic matter and contaminants such as endocrine disrupting compounds and pharmaceuticals in natural saline waters. (Collaboration with Stanford University.)
  • Bioavailability of organic pollutants in soot and char particles using in vitro simulated gastrointestinal models. Oral ingestion of soil is the principal pathway of human exposure to soil-borne contaminants. It is postulated that soil contaminants are not fully bioavailable due to desorption kinetic limitations. We are investigating the bioavailability of polycyclic aromatic hydrocarbons, nitro polycyclic aromatic compounds, and soil-applied herbicides sorbed to smokestack soot and biochar in an in vitro system that employs digestive enzymes and surfactants, food substances, and a third-phase polymer sink to mimic absorption by the intestinal lining (collaboration with University of Massachusetts, Amherst and Peking University).
  • Driving forces controlling the sorption and reactions of organic compounds by natural organic matter and black carbon. Soil organic matter, coaly substances and black carbon are the predominant sorbents of organic compounds in soils and sediments. We are using paramagnetic, 13C-labelled, deuterium-labelled and perhalogenated probe compounds in solid state Nuclear Magnetic Resonance spectrometric experiments to test certain hypotheses regarding the mechanism of sorption. Among the issues we are addressing are, a) preferential sorption in specific microdomains, or through the operation of specific types of functional group interactions; b) the influence sorbent chemical and physical structure on sorption intensity; c) swelling during the sorption process. In addition, we are investigating electron-transfer reactions between oxidants and reductants that appear to be mediated by black carbon surfaces. Lastly, we continue to focus efforts toward elucidating the underlying causes of sorption hysteresis and highly-resistant desorption.  (Collaborations with Old Dominion University, University of Iowa, and Stanford University).
  • Potential of biochar for environmental remediation, plant disease suppression and greenhouse gas mitigation. Biochar is the carbonaceous byproduct of anaerobic pyrolysis of biomass waste. Due to its porous and active surface properties biochar has attracted attention as a potentially beneficial soil amendment in agriculture and environmental remediation. My group in collaboration with researchers at CAES and elsewhere has several thrusts in this area. i) We are investigating the use of biochar to remediate marine and land spills of crude oil. Initial experiments show that biochars can absorb more than their own weight of crude oil floating on seawater, and that natural microbial degradation of the imbibed oil is subsequently stimulated. ii) Added to soil, biochar inhibits emissions of the potent greenhouse gas, nitrous oxide, a byproduct microbial nitrification and denitrification. However, the mechanism is unknown. We are investigating the interaction of nitrous oxide with biochar in comparison with soil organic matter and minerals to determine whether biochar influences the bioavailability of nitrous oxide. iii) We and others have found that biochar may suppress allelopathy and plant root diseases, and favor the growth of beneficial mycorrhizal fungi. We have also shown that biochar is actively consumed by earthworms. We are investigating the resulting processing of the consumed biochar, and whether earthworms can be a useful means of delivering biochar deep into the rhizosphere. (Collaboration with Dr. Wade Elmer at CAES and researchers at other universities and institutions.)
  • Photocatalytic oxidation of contaminants in water. Photocatalytic oxidation, especially at solar wavelengths, is an attractive approach for removal of organic and inorganic contaminants in waste water. Polyoxometallates are considered in some applications as effective heterogeneous and homogeneous photocatalysts for achieving deep oxidation of organic contaminants in water.  My group is investigating the kinetics and mechanisms of these reactions with bulk oxidants such as dioxygen, hydrogen peroxide, peracetic acid, peroxymonosulfate, and peroxydisulfate. One of our interests is the treatment of salty waste waters, such as reverse osmosis retentates and oil/natural gas process waters. The high levels of halide and carbonate salts in such waters can dramatically influence the photochemistry through redox reactions with bulk and transient oxidant species.
  • Removal of quarantine and pre-shipment fumigants (methyl bromide) from fumigation vent streams. Methyl bromide is a valuable chemosterilant in international commerce for controlling invasive insects and other species, yet it is a potent ozone-depleting compound. The group is researching two approaches for removing methyl bromide from fumigation vent streams. One is catalytic oxidation using nanostructured ceramic catalysts, followed by dry-scrubbing the Br-containing products (HBr, Br2) from the effluent. A second approach is carbon capture and hydrolysis. (Collaboration with USDA-ARS, Stanford University, University of California at Berkeley and others).


Recent publications available from the author,, (see for a full list)

  • Effect of Adsorption Nonlinearity on the pH-Adsorption Profile of Ionizable Organic Compounds, Feng Xiao and Joseph J. Pignatello,* Langmuir (in press).
  • Comparison of Halide Impacts on the Efficiency of Contaminant Degradation by Sulfate and Hydroxyl Radical-Based Advanced Oxidation Processes (AOPs), Yi Yang, Joseph J. Pignatello, Jun Ma,* William A. Mitch,* Environ. Sci. Technol. (in press).
  • Influence of salinity on triplet-state natural organic matter loss by energy transfer and electron transfer pathways, Kimberly M. Parker, Joseph J. Pignatello, and William A. Mitch,* Environ. Sci. Technol. 47: 10987-10994 (2013).
  • The role of black carbon conductivity in mediating hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) degradation on carbon surfaces by nucleophilic substitution in the presence of sulfides, W. Xu, J. J. Pignatello, and W.A. Mitch,* Environ. Sci. Technol., 47 (13), 7129–7136 (2013).
  • Predicting Contaminant Adsorption in Black Carbon (Biochar)-Amended Soil for the Veterinary Antibiotic Sulfamethazine, M. Teixido, C. Hurtado, J.J. Pignatello*, J.L. Beltran, M. Granados and J. Peccia, Environ. Sci. Technol., 47 (12), 6197–6205 (2013).
  • New Insight into the Mechanism of Adsorption of Ionizable Compounds on Carbon Nanotubes, Xiaoyun Li, Joseph J, Pignatello,* Yiquan Wang, and Baoshan Xing;* Environ. Sci. Technol., 47, 8334-8341 (2013). DOI: 10.1021/es4011042.
  • Evidence of Micropore-filling for Sorption of Nonpolar Organic Contaminants by Condensed Organic Matter, Yong Ran,* Yu Yang, Baoshan Xing, Joseph J. Pignatello, Seokjoon Kwon, Wei Su, and Li Zhou, J. Environ. Qual. 42:806–814 (2013).
  • Catalytic Oxidation for Elimination of Methyl Bromide Fumigation Emissions Using Ceria-Based Catalysts, Chia-Ying Chen and Joseph J. Pignatello;* Applied Catalysis B: Environmental 142-143: 785–794 (2013).
  • Adsorption of Organic Compounds by Black Carbon from Aqueous Solution, J. J. Pignatello. In: “Molecular Environmental Soil Science," Jianming Xu and D.L. Sparks (Edits.); Progress in Soil Science Series; Springer; pp 359-385 (2013).
  • Laboratory Tests of Biochars as Adsorbents for Use in Recovery or Containment of Marine Crude Oil Spills, H.N. Nguyen and J.J. Pignatello,* Environ. Engineer. Sci., 30(7): 374-380 (2013).
  • Characterization of oil shale, isolated kerogen, and post-pyrolysis residues using advanced 13C solid-state nuclear magnetic resonance spectroscopy, Xiaoyan Cao, Justin E. Birdwell*, Mark Chappell, Yuan Li, Joseph J. Pignatello, and Jingdong Mao, AAPG Bulletin (Amer.  Assoc. Petroleum Geologists), AAPG Bulletin, 97(3): 421436 (2013).
  • Sorption Selectivity in Natural Organic Matter Studied with Nitroxyl Paramagnetic Relaxation Probes, C. Lattao, Y. Li, X. Cao, J. Mao, K. Schmidt-Rohr, M.A. Chappell, L.F. Miller, A.L. dela Cruz, and J.J. Pignatello,* Environ. Sci. Technol. 46: 12814-12822 (2012).
  • Advanced Solid-state NMR Characterization of Marine Dissolved Organic Matter Isolated Using the Coupled Reverse Osmosis/Electrodialysis Method, Jingdong Mao,* Xueqian Kong, Klaus Schmidt-Rohr, Joseph J. Pignatello, and E. Michael Perdue, Environ. Sci. Technol., 46, 5806–5814 (2012)
  • Impact of halide ions on natural organic matter-sensitized photolysis of 17ß-Estradiol and on singlet oxygen concentration in saline waters, Janel E. Grebel, Joseph J. Pignatello, and William A. Mitch,* Environ. Sci. Technol. 46: 7128-7134 (2012).
  • Dynamic interactions of natural organic matter and organic compounds, J.J. Pignatello*; J. Soils and Sediments, 12: 1241-1256 (2012) doi 10.1007/s11368-012-0490-4
  • Characterization of Wood Chars Produced at Different Temperatures using Advanced 13C Solid-state NMR Spectroscopic Techniques, Xiaoyan Cao, Joseph J. Pignatello, Yuan Li, Charisma Lattao, Mark A. Chappell, Na Chen, Lesley F. Miller, and Jingdong Mao,* Energy & Fuels. 26: 5983-5991 (2012).
  • Preparation and Characterization of Humic acid Cross-linked with Organic Bridging Groups, T. Schneckenburger; C.V. Lattao; J.J. Pignatello*, G.E. Schaumann, S. Thiele-Bruhn; XY Cao; JD Mao, Org. Geochem., 47 (2012) 132–138.
  • Speciation of the Ionizable Antibiotic Sulfamethazine on Black Carbon (Biochar), M. Teixido, J.J. Pignatello, J.L. Beltran, M. Grenados and J. Peccia,  Environ. Sci. Technol. 45: 10020–10027 (2011).
  • Sorbic acid as a quantitative probe for the formation, scavenging and steady-state concentrations of the triplet-excited state of organic compounds, J.E. Grebel, J.J. Pignatello, W.A. Mitch, Water Research, 45(19): 6535-6544 (2011).
  • Adsorption of Aromatic Carboxylate Ions to Charcoal Black Carbon is Accompanied by Proton Exchange with Water, Ni Jinzhi, J. J. Pignatello* and B. Xing, Environ. Sci. Technol. 45, 9240-9248 (2011). Correction: Environ. Sci. Technol. 46, 5633–5633 (2012).
  • Effect of Biochar Amendments on Mycorrhizal Associations and Fusarium Crown and Root Rot of Asparagus in Replant Soils, W.H. Elmer and J.J. Pignatello, Plant Disease 95: 960-966 (2011).
  • Effect of halide ions and carbonates on organic contaminant degradation by hydroxyl radical-based advanced oxidation processes, Janel E. Grebel, Joseph J. Pignatello, William A. Mitch; Environ. Sci. Technol., 44: 6822-6828 (2010).
  • Sources, Interactions, and Ecological Impacts of Organic Contaminants in Water, Soil, and Sediment: An Introduction to the Special Series, Joseph J. Pignatello, Brian G. Katz, and Hui Li; J. Environ. Qual., 39: 1133-1138 (2010).
  • Interactions of Anthropogenic Organic Chemicals with Organic Matter in Natural Particles, J.J. Pignatello, Biophysico-Chemical Processes of Anthropogenic Organic Compounds in Environmental Systems, B. Xing, N. Senesi and P. M. Huang (eds). Volume 3 of IUPAC SERIES ON BIOPHYSICO-CHEMICAL PROCESSES IN ENVIRONMENTAL SYSTEMS; Wiley; pp 3-50.

Content Last Modified on 2/27/2014 1:42:16 PM