Listen: Justin Chalker in conversation with Stephen O’Doherty
Polluted beaches, oily water, dead birds and marine life destruction caused by crude oil spills could be a thing of the past with pioneering new research led by Flinders University. An exciting, more sustainable answer to effectively clean up oil spill destruction follows development of a new way to quickly soak up crude oil with an absorbent polymer – itself made from waste products from the petroleum and refining industries.
In an environmental win-win, the new type of polymer made from waste cooking oil and sulphur (a by-product of the petroleum industry) has the ability to clean up crude oil and diesel spills. Better still, because this highly buoyant polymer acts like a sponge to absorb the waste materials from sea water, the polymer can be squeezed to recover the oil and then reused.
Award-winning scientist Dr Justin Chalker, Senior Lecturer in Synthetic Chemistry at Flinders University in Adelaide, South Australia, is leading an international research team responsible for the discovery. He is delighted that chemists are finding new ways to provide cheap and effective solutions to curb the damage caused by oil spills.
“This is an entirely new and environmentally beneficial application for polymers made from sulphur,” says Dr Chalker. “This application can consume excess waste sulfur that is stockpiled around the globe and may help mitigate the perennial problem of oil spills in aquatic environments.”
Deepwater Horizon Explosion Devastated Gulf of Mexico
Oil spills are a major global issue, with the International Tanker Owners Pollution Federation (ITOPF) reporting about 7000 tonnes of crude oil spilling from tankers into oceans in 2017 alone. A recent large oil spill off Borneo, for example, and prompted Indonesian authorities to declare a State of Emergency.
The international team of researchers point to the effects of recent large-scale spillage catastrophes as a potent reason driving their research – in particular, the explosion on the Deepwater Horizon offshore drilling rig in 2010 and subsequent release of approximately 4.9 million barrels of crude oil into the Gulf of Mexico.
Simple, Cheap and Efficient
“This is a new class of oil sorbents that is low-cost, scalable, and enables the efficient removal and recovery of oil from water,” says Dr Chalker. The findings are in new paper, ‘Sustainable Polysulfides for Oil Spill Remediation: Repurposing Industrial Waste for Environmental Benefit’, published in on-line journal ‘Advanced Sustainable Systems‘.
The researchers used the common waste substances – canola oil from cooking, sulphur which is a byproduct of the petroleum industry, plus sodium chloride – to create an inexpensive and sustainable sorbent that can mitigate the ecological harm of oil pollution. Sulphur and cooking oils are hydrophobic, so the new the polymer has an affinity for hydrocarbons such as crude oil and diesel fuel, and can rapidly remove them from seawater.
It removes mercury too
Get the feeling this story is a bit familiar? Actually it is. The first use the team discovered for the polymer was to clean up toxic mercury from the environment. On Open House we talked to Dr Chalker about the devastating effects mercury has on people, unborn children and the environment. Mercury is widely used in poor countries when people engage in small scale or ‘artisanal’ gold mining. Around a quarter of the gold mined each year comes from this kind of mining. Deadly mercury poisoning effects around 15 million people around the world, mainly in Africa, Asia and South America. Read the research paper here.
Developing nations will benefit
Hundreds of smaller spills of diesel fuel and other petroleum products affect developing countries in Africa, Asia and South America, for example in the Niger Delta and Amazon basin of Ecuador. The new material made from cheap and sustainable products will help respond to these developing countries where smaller, localised spills threaten groundwater, drinking water and important food staples such as fish.
This video produced by Animate Your Science demonstrates the polymer’s incredible clean-up ability. Absorption of the pollutant happens within a minute of the solution being sprinkled onto oil covering the surface of water.
The research was supported by the Australian Government National Environmental Science Program, Australian Research Council, Royal Australian Chemical Institute, Australian Microscopy and Microanalysis Research Facility, Australian National Fabrication Facility, FCT Portugal, The Royal Society, Engineering and Physical Sciences Research Council and European Research Council.
Photo credits: Flinders University, U.S. Coast Guard, U.S. Fish and Wildlife Service, Flicker
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