'Eureka' moment for solution to water contamination
A scientific breakthrough might have provided a solution to the issue of water contamination, say researchers at Houston Rice University and Lomonosov Moscow State University.
Experiments, reported in the Royal Society of Chemistry journal Physical Chemistry Chemical Physics, have demonstrated that the chemical graphene oxide has an extensive capability to quickly remove radioactive material from contaminated water.
Chemists James Tour and Stepan Kalmykov claim the discovery could improve the cleanups of contaminated sites like the Fukushima nuclear plant and cut the cost of hydraulic fracturing for oil and gas recovery.
Microscopic flakes of graphene oxide bind quickly to natural and human-made radionuclides and condense them into solids.
During experiments, graphene oxide proved far better than the bentonite clays and granulated activated carbon - traditionally used in nuclear cleanups.
In addition, graphene oxide is low cost, easily produced in bulk and biodegradable.
Lockheed Martin and Parsons Engineering former vice president and an expert in nuclear power and remediation who is working with the researchers, Steven Winston, said:
"In the probabilistic world of chemical reactions where scarce stuff (low concentrations) infrequently bumps into something with which it can react, there is a greater likelihood that the 'magic' will happen with graphene oxide than with a big old hunk of bentonite. In short, fast is good."
The researchers focused on removing rare radioactive isotopes from liquids.
Winston said: "Though they don't really like water all that much, they can and do hide out there. From a human health and environment point of view, that's where they're least welcome."
Naturally occurring radionuclides are also unwelcome in fracking fluids that bring them to the surface in drilling operations, according to Tour.
"When groundwater comes out of a well and it's radioactive above a certain level, they can't put it back into the ground," he said.
Tour added: "It's too hot. Companies have to ship contaminated water to repository sites around the country at very large expense. The ability to quickly filter out contaminants on-site would save a great deal of money."
Tour also sees potential benefits for the mining industry.
"Environmental requirements have essentially shut down U.S. mining of rare earth metals, which are needed for cell phones.
"China owns the market because they're not subject to the same environmental standards. So if this technology offers the chance to revive mining here, it could be huge," he said.