New Way to Clean Oil, Chemical Spills

Monday, March 3, 2014 @ 12:03 PM gHale


It is bad enough when there is an oil or chemical spill, but sometimes the cleanup is almost as damaging as the original spill.

That is why cleaning up oil spills and metal contaminates in a low-impact, sustainable and inexpensive manner remains a challenge for companies and governments globally.

RELATED STORIES
New Age Solar Cells Boost Efficiency
Hybrid Fuel Cell Energy from Biomass
Graphene for Wireless Communications
New Wave Organic Solar Cells

That may soon change as there are alternative materials that can end up modified to absorb oil and chemicals without absorbing water, said researchers at the University of Wisconsin–Madison. The technology may offer a cheaper and “greener” method to absorb oil and heavy metals from water and other surfaces.

Shaoqin “Sarah” Gong, a researcher at the Wisconsin Institute for Discovery (WID) and associate professor of biomedical engineering, graduate student Qifeng Zheng, and Zhiyong Cai, a project leader at the USDA Forest Products Laboratory in Madison, just created and patented the new aerogel technology.

Aerogels, which are highly porous materials and the lightest solids in existence, already see use in a variety of applications, ranging from insulation and aerospace materials to thickening agents in paints. The aerogel prepared in Gong’s lab consists of cellulose nanofibrils (sustainable wood-based materials) and an environmentally friendly polymer. Furthermore, these cellulose-based aerogels consist of an environmentally friendly freeze-drying process without the use of organic solvents.

It’s the combination of this “greener” material and its high performance that got Gong’s attention.

“For this material, one unique property is that it has superior absorbing ability for organic solvents — up to nearly 100 times its own weight,” she said. “It also has strong absorbing ability for metal ions.”

Treating the cellulose-based aerogel with specific types of silane after it goes through the freeze-drying process is a key step that gives the aerogel its water-repelling and oil-absorbing properties.

“So if you had an oil spill, for example, the idea is you could throw this aerogel sheet in the water and it would start to absorb the oil very quickly and efficiently,” she said. “Once it’s fully saturated, you can take it out and squeeze out all the oil. Although its absorbing capacity reduces after each use, it can be reused for a couple of cycles.”

In addition, this cellulose-based aerogel exhibits excellent flexibility as demonstrated by compression mechanical testing.

Though there needs to be more work before the aerogel can end up mass-produced, Gong said she remains eager to share the technology’s potential benefits beyond the scientific community.

“We are living in a time where pollution is a serious problem — especially for human health and for animals in the ocean,” she said. “We are passionate to develop technology to make a positive societal impact.”



Leave a Reply

You must be logged in to post a comment.