An multinational team lead by Professor Shizhang Qiao from the University
of Adelaide and Associate Professor Yao Zheng from the School of Chemical
Engineering effectively divided saltwater without pre-treatment to generate
green hydrogen.
Professor Qiao stated, "We have
electrolyzed natural seawater to make green hydrogen
with approximately 100% efficiency, using a non-precious and inexpensive
catalyst in a commercial electrolyser."
Cobalt oxide is a common non-precious catalyst that has chromium oxide on
the surface.
We utilized saltwater as a feedstock without requiring any pre-treatment
procedures, such as reverse osmosis desolation, purification, or
alkalization, Associate Professor Zheng said. A commercial electrolyser
using our catalysts performs almost as well in saltwater as one using
platinum/iridium catalysts with a feedstock of deionized water that has
undergone extreme purification.
"Current electrolysers are operated with exceptionally pure water
electrolyte," Professor Zheng continued. Freshwater supplies are becoming
increasingly scarce, and increased demand for hydrogen to partially or
completely replace energy produced by fossil fuels will dramatically worsen
this situation.
Seawater is regarded as a natural feedstock electrolyte and is a nearly
limitless supply. This makes more sense in areas with extensive coasts and
lots of sunshine. It cannot be used in areas with limited access to
saltwater, though.
Due to corrosion caused by employing saltwater and electrode side
reactions, seawater electrolysis is still in its infancy when compared to
pure water electrolysis.
According to Zheng, "traditional electrolysers, including desalination and
deionization, always need the treatment of unclean water to a degree of
water purity, which raises the operating and maintenance costs of the
processes." "Our study offers a way to directly utilize saltwater without
the need for pre-treatment systems and alkali addition, which displays
equivalent performance to that of the existing metal-based mature pure water
electrolyser."
The group will seek to scale up the system using a bigger electrolyzer so
that it may be utilized in industrial operations like ammonia synthesis and
hydrogen production for fuel cells.
***
If this research is replicated and is successful, it will be a
breakthrough. There are no pricey precious metals used. Cobalt, however, is
not that uncommon but is far from plentiful and is frequently obtained from
ore that is gathered by young children. As a result, predicting the future
of cobalt is quite difficult. Should this study be successful, cobalt prices
would rise dramatically and demand would skyrocket. There is cobalt to be
gotten; it's only hidden behind "not in my backyard" and the legal
restrictions put up by environmental green organizations, which
significantly clog up politics.
The absence of discussion of the power source is the second issue. The
input vs. product computation isn't demonstrated or addressed, despite the
fact that the energy input is unquestionably electric and the claim of
efficiency is close to 100%.
However, there is a lot of excitement about the idea of a far lower water
supply cost and the avoidance of precious metals. A hearty congratulations
to the group is due. Let's hope the next phases can be completed with little
expense and without needing years of political wrangling.
By Brian Westenhaus via
New Energy and Fuel
