However, the water can't be disinfected with chlorine because it degrades polyamid material. Now, researchers at Virginia Tech have created a new polymer membrane for RO that will not be degraded by chlorine.
They will present the research at the 232nd National Meeting of the American Chemical Society on September 10-14 in San Francisco.
"Our RO materials grew out of our work on proton exchange membrane (PEM) materials used in fuel cells," said James McGrath, University Distinguished Professor of Chemistry at Virginia Tech. "The polymer structure is similar, but PEM materials are treated with a dilute acid and the RO materials are treated with a salt to put them in the neutral form."
Last year, McGrath's group received funding from the Office of Naval Research (ONR) to develop an RO material that would not break down from chlorine. "We have suggested for some time that PEM materials could be used so our students quickly began sending sample materials for testing to Benny D. Freeman, chemical engineer at the University of Texas, Austin. And within a year we had a successful material. "People have been doing RO for 40 years, but not with this new material," McGrath said.
Post doctoral Associate Zhong-Biao Zhang will deliver a paper on how the new materials are made and how they work at 2:20 p.m. Wednesday, Sept. 13, in Salon B3 of the Marriott. Authors of "Synthesis of di-sulfonated poly(arylene ether sulfone) random copolymers as novel candidates for chlorine-resistant reverse osmosis membranes (PMSE 494)" are Zhang, Virginia Tech graduate students Guang-Yu Fan and Mehmet Sankir, Ho Bum Park and Freeman at the University of Texas, and McGrath.
The ONR has expanded the project to add Don Baird, professor of chemical engineering at Virginia Tech, to fabricate the membrane. "The material we created and evaluated in the first year was relatively thick," McGrath said. "To be competitive, it has to be a thin film so the water can pass through quickly -- 10 to 100 times thinner than our present samples. That is not trivial but we think we know how to do it."
The Virginia Tech research group has created an asymmetric membrane. Imagine rigid foam with a thin membrane skin. The separation takes place at the skin and the water passes quickly through the foam's large pores. Without the foam, the skin or film layer is not strong enough to withstand the pressure of RO.
McGrath is now looking for companies to work with to produce the new material.
He is also working on a different process to separate ethanol from water. "We think we can make membranes to do that too," he said.
Susan Trulove | EurekAlert!
The body's street sweepers
18.12.2017 | Ludwig-Maximilians-Universität München
Life on the edge prepares plants for climate change
18.12.2017 | Max-Planck-Institut für Entwicklungsbiologie
A study carried out by an international team of researchers and published in the journal Physical Review X shows that ion-trap technologies available today are suitable for building large-scale quantum computers. The scientists introduce trapped-ion quantum error correction protocols that detect and correct processing errors.
In order to reach their full potential, today’s quantum computer prototypes have to meet specific criteria: First, they have to be made bigger, which means...
Since 2016, German and Spanish researchers, among them scientists from the University of Göttingen, have been hunting for exoplanets with the “Carmenes”...
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
18.12.2017 | Life Sciences
18.12.2017 | Materials Sciences
18.12.2017 | Life Sciences