Virginia Tech Department of Chemistry faculty and students are assisting the U.S. military in creating new materials that can trap and destroy chemical warfare agents, such as sarin and VX nerve gas.
“These compounds represent some of the most toxic chemicals ever created, yet there currently are few methods available for safely removing them from the environment,” said John Morris, professor of chemistry with the Virginia Tech College of Science, and the lead investigator on the project. "The ultimate aim of our research team is to develop materials that might be incorporated into air filters, fabrics, and gas masks for soldier and civilian protection.”
Supported by a $3 million multi-university grant from the U.S. Department of Defense, the research team is composed of scientists from Emory University in Atlanta, Brookhaven National Laboratory in New York, and the U.S. Army’s Edgewood Chemical and Biological Center in Aberdeen, Maryland.
An additional local key team contributor is Diego Troya, an associate professor with Virginia Tech’s chemistry department and an expert in computational studies of surface chemical reactions.
Laboratory studies carried out by Morris’ group at Virginia Tech are focusing on uncovering the molecular-scale reaction pathways and determining the reaction rates when nontoxic mimics of chemical warfare gases, which are fully benign, come in contact with catalytically active materials being developed by researchers at Emory University.
These fundamental studies held at Virginia Tech will then inform more applied experiments underway at Brookhaven and Edgewood Chemical and Biological Center, including advanced experiments employing actual chemical warfare agents at the latter facility. Experimental results will then be used to develop rules for understanding how a catalyst’s chemical structure can be changed to improve the efficiency of the reactions.
Computational studies will provide true atomic-scale chemical insights.
Josh Abelard, of Williamsburg, Virginia, and Conor Sharp, of Arlington, Virginia, both doctoral students in the Department of Chemistry, are spearheading the experiments at Virginia Tech’s Hann Hall-South.
“We want to use these new materials to ‘trap’ the chemical warfare agents and then perform a reaction on the chemicals using moisture from the atmosphere to break down the chemical weapons into much less toxic molecules,” said Sharp. “We want catalytic materials that can be reusable and work as well the 100th time as it does the first time.”
Added Abelard: “The engineering phase is already under way. Our role is to help engineers understand why their current materials do or do not work well, and make recommendations for improvements.”
Materials being tested may one day be used in respirator cartridges, air filters, and clothing to protect both military personnel and the general public.
“While we cannot stop the use of chemical weapons, we can do our best to ensure that people are protected from chemical attacks,” added Sharp.
Morris has cited the excellent facilities, graduate students, and surface science capabilities at Virginia Tech as key factors in attracting federal funding for the project.
“We are fortunate to have an outstanding group of analytical and physical chemistry graduate students here at Virginia Tech,” said Morris. “The students will also travel to national laboratories, where they will be some of the first scientists to use high-energy X-rays to explore this type of catalysis under real-world conditions.”
Sharp already has performed experiments at Argonne National Lab near Chicago and the SLAC National Accelerator Lab in Palo Alto, California.
“One of the experimental techniques we employ uses high-energy X-ray light to examine how the metal in our catalysts changes during a reaction,” he said. “We want to see how our catalyst materials will interact with toxic chemicals, and this is a very sensitive experimental technique. You generally have a narrow time allotment to perform experiments, so you end up using 24 hours a day, every day of the run, to collect data.”
A typical experiment at a national laboratory may last for up to five days, added Morris.
Computer simulations by Troya and his Ph.D. student, Robert C. Chapleski Jr., of Severn, Maryland, will capture details that are difficult to measure, allowing the research team to augment the experiments by learning about components of the reactions that are obscured in the experiments.
“In addition, we can probe the actual chemical warfare agents with the computer without any exposure risk,” added Troya.