Tag Archives: Baiyu Zhang

Reusable ‘sponge’ for soaking up marine oil spills—even in northern waters

A May 28, 2024 news item on phys.org announces some new research into sponges, a topic of some interest where oil spill cleanups are concerned,

Oil spills, if not cleaned up quickly and effectively, can cause lasting damage to marine and coastal environments. That’s why a team of North American researchers are developing a new sponge-like material that is not only effective at grabbing and holding oil on its surface (adsorption), but can be reused again and again—even in icy Canadian waters….

A May 27, 2024 Canadian Light Source (CLS) news release (also received via email) by Rowan Hollinger provides some details, Note: CNF can be cellulose nanofibers, cellulose nanofibrils, or, it’s sometimes called, nanofibrillated cellulose (NFC) (see Nanocellulose Wikipedia entry),,

The special material – called CNF-SP aerogel — combines a biodegradable cellulose-based material with a substance called spiropyran, a light-sensitive material. Spiropyran has a unique ‘switchable’ property that allows the aerogel to go between being oil-sorbent and oil-repellent, just like a kitchen sponge that can be used to soak up and squeeze out water.

“Once spiropyran has been added to the aerogel, after each usage we just switch the light condition,” explains Dr. Baiyu Helen Zhang, professor and Canada Research Chair at Memorial University, Newfoundland. “We used the aerogel as an oil sorbent under visible light. After oil adsorption, we switched the light condition to UV light. This switch helped the sponge to release the oil.”

And the material continues soaking up and releasing oil, even when the water temperature drops, according to Dr. Xiujuan Chen, an assistant professor at University of Texas – Arlington.

“We found that when we tested the oil sorbent’s performance under different kinds of environmental conditions, it had a very good performance in a cold environment. This is quite useful for cold winter seasons, particularly for Canada.”

The researchers used the CLS’s Mid-IR beamline to examine the characteristics of the aerogel before and after exposing it to visible and UV light. From here, the researchers are looking to scale up their research with large pilot studies and even testing the material in the field.

“The CLS has very unique infrastructure that supports students and researchers like us to conduct many kinds of very exciting research and to contribute to scientific knowledge and engineering applications,” says Zhang.

Here’s a link to and a citation for the paper,

Development of a spiropyran-assisted cellulose aerogel with switchable wettability as oil sorbent for oil spill cleanup by Hongjie Wang, Xiujuan Chen, Bing Chen, Yuming Zhao, Baiyu Zhang. Science of The Total Environment Volume 923, 1 May 2024, 171451 DOI: https://doi.org/10.1016/j.scitotenv.2024.171451 Available online: 2 March 2024 Version of Record: 8 March 2024

This paper is behind a paywall.

The CLS has made this video of the researchers available,

For the curious, I have many posts about sponges and, in particular, sponges for use in environmental cleanups.