Found in solid-rocket fuel, roadside flares and fireworks, perchlorate is a dangerous contaminant that can disrupt thyroid function by interfering with the uptake of iodine. Infants and fetuses are believed to be particularly at risk from the effects of perchlorate exposure.
Because perchlorate is readily soluble in water, it can be transported vast distances in groundwater or rivers. A plume of contaminated groundwater from a manufacturing plant near Las Vegas, for example, reached the Colorado River and spread throughout the Southwest. Cleanup could take decades. "Perchlorate has been recognized as a significant environmental contaminant in U.S. water supplies, and its physical and chemical properties pose a serious challenge for remediation," said John Shapley, a professor of chemistry at Illinois and co-developer, with graduate student Keith Hurley, of the new catalyst.
Efforts at remediation using naturally occurring microorganisms or existing pump-and-treat technology are too complicated, too energy intensive or too slow to be practical, Shapley said.
The new catalyst is composed of two metals – palladium and rhenium – supported on activated carbon. The catalyst operates at room temperature under normal atmospheric pressure, and does not dissolve in water.
"In catalytic operation, the rhenium removes an oxygen atom from the perchlorate molecule in what is called an atom transfer reaction," Hurley said. "Meanwhile, the palladium activates the gaseous hydrogen atoms so they will react with the freed oxygen. What's left is harmless chloride and water." The catalytic reaction continues as long as there is both hydrogen gas and perchlorate contaminant present.
"While current technologies – such as ion exchange systems – can concentrate and remove perchlorate from water, they cannot destroy it," said Shapley, who will describe the new catalyst at the national meeting of the American Chemical Society, to be held in San Francisco, Sept. 10-14. "Our catalyst would take a concentrated stream of perchlorate and get rid of it altogether."
James E. Kloeppel | EurekAlert!
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy