Media Release
May 28 2008
Nano-solution to clean drinking water
UniSA scientists have discovered a simple way to remove bacteria and
other contaminants from water using tiny particles of pure silica coated
with an active nano-material.
The water treatment process is a new concept, not used anywhere else in
the world, which has the potential to make a significant contribution to
the health of nations worldwide.
A recent UNESCO report reveals that more than 6,000 people die every day
from water-related diseases, and the availability of drinking quality
water, especially in the developing world, is fast becoming a major
socio-economic issue.
The report also states that waste water pollutants from industries such
as pulp and paper mills, textiles and leather factories, steel foundries
and petrochemicals refineries are a major cause of illness in some parts
of the world where inadequate regulations leave people subject to toxic
industrial outflows.
Professor Peter Majewski and PhD student Chiu Ping Chan from UniSA’s
School of Advanced Manufacturing and Mechanical Engineering developed
the new technique, which can remove bacteria, chemicals, viruses and
other contaminants from water much more effectively than conventional
water purification methods.
“Its major benefits include an easy to use chemical and physical
treatment process that cleans water without requiring additional energy,
and uses recyclable non-toxic base materials like the waste product
silica and water, which bring costs down,” Prof Majewski said.
“These features make it a very attractive alternative to desalination,
which incurs high energy costs,” he said.
Prof Majewski says current water purification techniques are often
complicated and use sophisticated equipment, which is expensive to
operate and maintain, and includes a final, costly disinfection stage.
“Our technology is simple. We coat tiny silica particles with a
nanometer-thin layer of an active material based on a hydrocarbon with a
silicon-containing anchor. The coating is made by a chemical
self-assembly process, which involves simply mixing the ingredients to
make what is called active ‘surface engineered particles’,” Prof
Majewski said.
“We put the prepared particles in the contaminated water and stir it, or
flush the contaminated water through a filter containing the active
particles, which is much easier to handle. As the water runs through the
filter, the toxins attach themselves to the coated particles through an
electrostatic attraction between the contaminants and the particles and
remain in the filter, leaving good quality water of drinking standard,”
he said.
Testing of the active particles demonstrates that they can remove
pathogens such as the Polio virus, bacteria such as Escherichia coli,
and the waterborne parasite Cryptosporidium parvum.
In addition to cleaning water for drinking, UniSA’s water purification
technology is suitable for a broad range of uses including home use such
as cold water refrigeration to ensure that there is no bacterial
contamination, and for cleaning swimming pools and ornamental ponds.
Prof Majewski says that all water can be treated and his researchers are
looking into processed water treated for reuse in industry, which
requires fewer regulations than drinking water.
The UNESCO report also states that waste water pollutants from
industries such as pulp and paper mills, textiles and leather factories,
steel foundries and petrochemicals refineries are a major cause of
illness in some parts of the world where inadequate regulations leave
people subject to toxic industrial outflows.
“UniSA’s water purification process using nanotechnology could help to
prevent disease and poisoning for potentially millions of people
worldwide. The good news is that it should be available within two
years.”
Contact for interview
- Prof Peter Majewski office (08) 8302 3162 mobile 0423 783 662 email peter.majewski@unisa.edu.au
Media contact
- Geraldine Hinter office (08) 8302 0963 mobile 0417 861832 email geraldine.hinter@unisa.edu.au