Jim Amonette
Senior Research Scientist, Fundamental and Computational Sciences Directorate, Chemical and Material Sciences Division, Environmental Dynamics and SimulationDual Assignment
WR Wiley Environmental Molecular Sciences Laboratory / Environmental Spectroscopy & Biogeochemistry Facility
Current Activities and Projects
Dr. Amonette currently has projects involving 1) aspects of terrestrial soil carbon sequestration with a focus on amendments (such as fly ash and charcoal) and management regimes (moisture), 2) monitoring, measurement, and verification approaches for geological carbon sequestration, and 3) the hydrolytic and reductive degradation pathways of chlorinated hydrocarbons including the redox chemistry associated with iron-bearing clays and nanoparticles.
Research Interests
Dr. Amonette specializes in the areas of environmental geochemistry and soil mineralogy. He is interested in the structure and chemistry of minerals and in the application of spectroscopic techniques, such as laser photoacoustic, Mössbauer, electron paramagnetic, infrared, and x-ray absorption/scattering, to characterize the solid phases and to predict and monitor the reactions that occur in soil environments.
Dr. Amonette has long had a keen interest in the fundamental properties of clay minerals as well as their applications to environmental problems. His contributions include dissertation work on the role of structural iron in mica weathering, analytical techniques for the determination of ferrous iron and for the semi-quantitative modal analysis of clay minerals in soils, reduction of iron-bearing smectites for remediation processes, synthesis and properties of hydrotalcites for adsorption of anions, modification of natural layer silicates for adsorption of Cs and Sr, and a chapter on the environmental chemistry of iron that includes a theoretical approach for estimating reduction potentials for iron in silicate minerals. He continues to focus much of his work on zerovalent and ferrous iron chemistry, and its potential use for environmental remediation.
The geochemical mechanisms by which C can be retained in soils and sediments are acquiring great importance due to climate-change concerns. For nearly a decade, Dr. Amonette co-led a team working on the fundamental molecular-scale aspects of carbonate mineral dissolution and growth processes using a combination of atomic-force microscopy and theoretical calculations. More recently he has focused on the catalytic mechanisms that promote the formation of humic materials. The chemistry of charcoal and fly ash are of particular interest as these common materials could be applied as soil amendments to promote carbon sequestration.
Dr. Amonette has worked on the precipitation/dissolution chemistry of Cr(III) and Cr(VI) in soils. He identified the solid solution Ba(S,Cr)O4 as a possible phase controlling the aqueous concentrations of Cr(VI) species and determined the solubility products of several Ba(S,Cr)O4 solids. He also provided infrared spectroscopic evidence for the existence of the amorphous (Fe,Cr)(OH)3 solid solution and for the association of carbonate with Cr in the structure of this compound. Recently, he used laser photoacoustic spectroscopy to measure the kinetics and thermodynamics of trace-level chromate sorption to iron oxides.
Past Experience
Dr. Amonette has more than 26 years of research experience. He has authored or coauthored over 50 peer reviewed scientific journal publications, ten book chapters, 40 technical reports, four patents in the area of photoacoustic spectroscopy, and a book on quantitative methods in soil mineralogy. He joined PNNL in 1986 and has been associated with the Environmental Dynamics and Simulation group in the EMSL since 1990.
Education
BS, Soil Science, New Mexico State University, 1979
MS, Soil Chemistry, Iowa State University, 1983
PhD, Soil Chemistry, Iowa State University, 1988
Awards, Honors, & Appointments
- Chair, Soil Mineralogy Division, Soil Science Society of America, 1994
- Associate Editor, Soil Mineralogy Division, Soil Science Society of America Journal, 1994-1996
- Bouyoucos Conference Co-Organizer, Soil Science Society of America, 2004
- Associate Editor, Clays and Clay Minerals, 1998-2007
- Council Member, Clay Minerals Society, 1996-1998, 2007-2009
- Meeting Co-Chair, Clay Minerals Society, 2004
- Chet Cooper Mentor of the Year, Environmental and Health Sciences Division, PNNL, 2000
- R&D100 Award for "In-Situ Redox Manipulation", 1998
