How clean water technologies could get a boost from X-ray synchrotrons


Date:
July 28, 2020
Source:
DOE/SLAC National Accelerator Laboratory
Summary:
Scientists argue that research at synchrotrons could help improve
water- purifying materials in ways that might not otherwise be
possible.



FULL STORY ==========================================================================
The world needs clean water, and its need is only going to grow in the
coming decades. Yet desalination and other water-purifying technologies
are often expensive and require a lot of energy to run, making it that
much harder to provide more clean water to a growing population in a
warming world.


==========================================================================
To move forward, researchers should use tools such as those available at
X-ray synchrotrons to better measure the properties of materials involved
in purifying salty or otherwise contaminated water, argue scientists at
the Department of Energy's SLAC National Accelerator Laboratory and the University of Paderborn in Germany, "This is an opportune time for the
country really -- national labs, academia and industrial partners --
to advance the science related to desalination" and other clean water technologies, said Michael Toney, a distinguished scientist at SLAC's
Stanford Synchrotron Radiation Lightsource. Toney together with coauthors
SSRL scientist Sharon Bone and Paderborn's Professor Hans-Georg Steinru"ck
have just published a new perspective on advancing clean water technology
in the journal Joule.

The challenge is substantial. Around the world, billions of people
struggle to find clean drinking water at least one month a year, and projections suggest that demands for water in some parts of the U.S. -- including California, which struggles with droughts -- will outpace
supply by about 2050.

On top of that, desalinating or otherwise cleaning water is often costly
and energy inefficient -- and it's not always clear how to improve
those technologies.

For instance, in membrane reverse osmosis, saltwater flows over a
membrane under pressure, pushing clean water through the membrane into a freshwater stream and retaining salt, organics, and contaminants on the
salty water stream. Yet researchers do not understand in much detail
the physical and chemical processes responsible for that filtering
or how some of the pitfalls of reverse osmosis -- such as fouling,
the accumulation of organic and inorganic matter on the membrane --
interfere with the process.

"It's the complexity of these systems that make them so difficult to
probe, and that's why the synchrotron is so valuable, because it allows
us to probe that," Prof Steinru"ck said.

If researchers did understand better how reverse osmosis worked and how
it can get fouled up, they could find clues to improve the process and to develop new materials for clean water technologies. X-ray spectroscopy,
for example, could reveal which molecules are most responsible for
fouling. X-ray scattering experiments and imaging methods, such as
electron microscopy, could give scientists and engineers a better picture
of what's happening on a fine scale.

The same goes for other techniques, such as capacitive ionization,
a technique that works best on low-salinity or brackish groundwater
and is closely related to cutting-edge battery research. What's more,
this fine-scale understanding could allow researchers to design new
materials for desalination and to mitigate fouling.

That kind of research is also an opportunity for scientists to make more
of a direct impact on an increasingly pressing global problem -- a factor
that motivated Bone, who also works to understand how pollutants and
nutrients alike cycle through natural ecosystems, to work with colleagues
at SLAC and chemical engineers at Stanford University on clean water technologies. Working with Stanford chemical engineering graduate student Valerie Niemann and Professor William Tarpeh, Bone and Toney have already
begun investigating how foulants accumulate on reverse osmosis membranes.

"I wanted to join this effort because I saw it as an opportunity to
directly work on a technology that could make an impact in the face of
climate change," Bone said.


========================================================================== Story Source: Materials provided by
DOE/SLAC_National_Accelerator_Laboratory. Original written by Nathan
Collins. Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Sharon E. Bone, Hans-Georg Steinru"ck, Michael F. Toney. Advanced
Characterization in Clean Water Technologies. Joule, 2020; DOI:
10.1016/ j.joule.2020.06.020 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/07/200728150652.htm

--- up 1 week, 6 days, 1 hour, 55 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)