Mason B. Tomson, Ph.D., P.E. Professor, Civil and Environmental Engineering Director, Brine Chemistry Consortium Co-Director, China-US Center for Environmental Remediation and Sustainable Development Rice University

Dr. Mason B. Tomson is a Professor of Civil and Environmental Engineering at Rice University. While at Rice, he has directed research grants totaling over fifteen million dollars. His research team was one of the first (circa 1978) to prove that ground water could be readily contaminated by organic chemicals from the surface; they then developed and demonstrated the concepts of facilitated (enhanced) transport and more recently of irreversible (resistant) desorption of chemicals from soils and sediments.  These concepts have since been applied to fullerene and activated carbon nanoparticles.  Professor Tomson directs four research projects, two from NSF on nanotechnology, one from EPA on heavy metals in sediments, and a Brine Chemistry Consortium of eighteen oil and gas production and service companies.  Professor Tomson also leads an effort to establish a joint program between Rice University and Nankai University in Tianjin, China, on sustainable environmental development. 

Dr. Tomson has authored or coauthored over 200 articles in high impact journals, including Science, Journal of the American Chemical Society, Environmental Science and Technology, and Oil and Gas Journal; he holds four patents and has authored two books.  He also serves on the editorial boards of J. Envi. Sci. and Health, SPE Production and Facilities J., on the Science Advisory Committee of EPA’s IPEC at U. of Tulsa, and on the Steering Committee of the SPE Oilfield Scale Annual Conference in Scotland. 

Presentation Description
Transport of carbon and metal-oxide nanoparticles in soil and soil components
Nanoparticle transport in soils is of concern for the fate of the nanoparticles and for what they might co-transport as sorbed contaminants.  Numerous efforts have focused on describing the movement of these particles in monodisperse porous media, such as grass beads or sand, but little progress has been made in transferring those observations to heterogeneous soils, let alone, what happens to sorbed contaminants in these natural porous media.  We started with a well-defined soil and systematically added and removed fractions to identify the key materials and structures that account for nano-particle transport in batch and soil columns in the presence and absence of typical surface active materials.  A range of solution compositions common to natural waters have been examined.  Focus has been on nano-C60, magnetite, and anatase.  Then, by pre-equilibrating these nanoparticles with contaminants we have demonstrated facilitated transport of nanoparticles and resistant desorption of co-transported adsorbents.  Sorption isotherms and particle interaction theory have been combined with standard transport models to present, for the first time, a realistic view of nanoparticle transport in a natural soil.