Chinese researchers have developed a method of removing oil from polluted water using tiny barbed spikes that mimic the natural design of a cactus. Writing in the journal Nature Communications, the Beijing-based researchers describe how arrays of tiny copper spikes, similar to the cone-shaped spikes of a type of cactus known as Opuntia microdasys,
Even small amounts of oil leave a fluorescent sheen on polluted water. This oil sheen is difficult to remove—until now. According to a recently published article in the journal Chemosphere, an inexpensive new method has been developed to remove oil sheen by repeatedly pressurizing and depressurizing ozone gas, creating microscopic bubbles that attack the oil so it can be removed by sand filters.
“We are not trying to treat the entire hydrocarbon content in the water — to turn it into carbon dioxide and water — but we are converting it into a form that can be retained by sand filtration, which is a conventional and economical process,” says lead author Andy Hong, University of Utah professor of civil and environmental engineering.
Hong says the technology — for which patents are pending — could be used to clean a variety of pollutants in water and soil, including: