Novel Reusable Sponge Could Revolutionize Ocean Oil Spill Cleanup

R&D 100 Staff
March 9, 2018, 3:29 p.m.

In April of 2010, the oil-drilling rig Deepwater Horizon exploded and sank off the Gulf of Mexico. Over the course of 87 days, an estimated 200 million gallons of oil spilled into the ocean, resulting in the largest oil spill in the history of marine oil drilling operations, according to the EPA. Controlled burns of the oil were conducted in an attempt to clean up what was on the surface, and the resulting smoke pumped more than one million pounds of black carbon pollution into the atmosphere, according to a study published by the National Oceanic and Atmospheric Administration (NOAA).

The oil under the surface of the water, which stretched for at least 20 miles, was left for nature to deal with, as there was no technology capable of capturing it.

Oleo Sponge, a newly created absorbent for cleaning up oil spills, was created to ensure the environmental damage caused by Deepwater Horizon is never repeated.

The technology—designed by scientists at Argonne National Laboratory—is based on low-cost materials and processing, can capture 90 times its own weight in oil from both above and below the water’s surface, and is reusable.

It is also a 2017 R&D 100 Winner, as well as a R&D 100 Awards Editor’s Choice recipient and the R&D 100 Award Gold Award recipient for Special Recognition in Green Tech.

“What’s special about our technology is that we can extract the oil, either from the surface or from the water column, without creating any waste,” explained Seth B. Darling, the director of the Institute for Molecular Engineering at Argonne National Laboratory and the project lead on Oleo Sponge, in an interview with R&D Magazine. “We soak up the oil, and then the oil can be recovered, which is also added value because that can now be used—it was extracted from the Earth for a reason—and you can reuse the sponge. That allows you to address a much larger spill incident with a small amount of the absorbent.”

The idea behind Oleo Sponge

Darling and his team at Argonne did not initially set out to create a solution for oil spills. His team had been working for years on a new way to make material, known as Sequential Infiltration Synthesis (SIS), as a basic science exercise with no specific goal application or vision.

Then an article Darling read sparked an idea.

“A little over two years ago I was reading a paper from other researchers about trying to make something to soak up oil, and I thought, ‘we can do better than that by applying this SIS technique,’” said Darling.

About a month later, the opportunity to turn his idea into practice came—the U.S. Coast Guard put out a call for proposals for better ways to clean up oil spills. Darling and his team submitted a white paper about SIS and were asked to make a full proposal. Shortly after, they were funded to investigate the potential of SIS, and what eventually became Oleo Sponge, for the removal of oil.

“This is a really nice example of basic science happening in a government lab, and then becoming—by working with other parts of the government—something that is really a technology,” said Darling. “Often our government tends to be relatively siloed, and this was a really nice example of integration between the Department of Energy, Homeland Security, which owns the Coast Guard, and eventually the Department of the Interior. We had the science and technology here in the DOE and it was a challenge in the real world that was faced by Homeland and the DOI.”

Pilot-scale testing of Oleo Sponge. Credit: Argonne National Laboratory

How it works

The basis of the Oleo Sponge is created out a polyurethane, a common, inexpensive material.

“It is super cheap and it is already manufactured on a huge scale already so that is great about it,” said Darling. “The problem with polyurethane foam is that it doesn’t love oil and hate water. So what we have to do is change the surface chemistry of all of the little struts and fibers that make up that foam on a microscopic level so that they have that property.”

This is done by performing a two-step surface chemical treatment. In the first step, the foam is impregnated with an ultra-thin, inorganic coating using SIS. To perform SIS, the polymer is alternately exposed to two molecular precursor vapors that cause inorganic materials to grow within the polymer. The first precursor diffuses into the polymer and reacts with specific chemical functional groups on the polymer chains in a self-limited manner.

Oleo Sponge’s creators described the process in detail to R&D Magazine.  

“Polyurethane contains carbonyl (C=O) and amine (N-H) functional groups that are binding sites for trimethyl aluminum (TMA), the first precursor molecule in the SIS reaction to grow aluminum oxide. The SIS precursors readily diffuse throughout the porous network and access each of the microscopic fibers that constitute polyurethane foam. Following a brief purge step to remove the unreacted TMA, the foam is exposed to the second precursor, H2O vapor, which selectively reacts with the TMA-modified polyurethane, also in a self-limited manner. Additional SIS cycles of alternating precursors (TMA, H2O, TMA, H2O…) continue to grow the Al2O3 inside the polymer.”

This “primes” the surface for the next step. In the second step, the resulting surface is functionalized with an oleophilic monolayer using silanization, a self-limiting surface chemical reaction. Below is the Oleo Sponge researchers description of this process.

“To impart the Oleo Sponge with a high affinity for oil, we selected a silanization molecule with an oleophilic methacryloxypropyl group. The methacryloxypropyl group is chemically similar to oil, so that it bonds strongly with oil but not with water. Furthermore, the silanization molecule is selected to contain methoxy (O-CH3) functional groups that react strongly with the hydroxyl (OH) groups remaining from the SIS treatment. Therefore, this chemical reaction between the silanization molecule and the SIS-treated foam surface is very fast and efficient, and it renders the foam surface oleophilic and hydrophobic. This silanization step completes the transformation of the polyurethane foam into a highly selective oil absorber, the Oleo Sponge.”

Pilot-scale tests of the Oleo Sponge were performed at the National Oil Spill Response Research & Renewable Energy Test Facility, in Middletown, New Jersey using enough Oleo Sponge to cover a 64 square foot panel. During the test, the Oleo Sponge showed improved absorption capacity, selectivity, absorption rate, and reusability than commercial absorbent materials. This was the first known successful demonstration of subsurface oil removal by any technology.

Looking forward

With pilot testing completed and an R&D 100 Award win behind them, Darling and his team are looking to the future.

They are working to further improve their technology, expanding its abilities so it can absorb other pollutants from water such as heavy metals like lead, radionuclide and mercury.

“There are all kinds of things that end up in water that you don’t want to be there,” explained Darling. “So we are playing with the surface chemistry in different ways to target different things.”

They are also working to scale up their process for more continuous manufacturing, with the goal of soon finding a partner to commercialize the technology.

“We’ve got intellectual property associated with this and the idea would be to license that intellectual property to a private partner, and they, either independently or in partnership with us, would develop it into projects that can get out there in the real world,” said Darling.  “We are hoping that happens soon.”

Apply for the 2018 R&D 100 Awards

Oleo Sponge, by Argonne National Laboratory, was a 2017 R&D 100 Award winner. The winners were announced at The R&D 100 Awards Gala held in Orlando, Florida on Nov. 17, 2017. See the full list of 2017 R&D 100 Award Winners here.

The R&D 100 Awards have served as the most prestigious innovation awards program for the past 56 years, honoring R&D pioneers and their revolutionary ideas in science and technology.

Submissions for the 2018 R&D 100 Awards are now being accepted. Any new technical product or process that was first available for purchase or licensing between January 1, 2017 and March 31, 2018, is eligible for entry in the 2018 awards. Entries for the R&D 100 Awards can be entered under five general product categories— Mechanical Devices/ Materials, IT/Electrical, Analytical/Test, Process/Prototyping, and Software/Services.

The deadline is June 1, 2018.

To apply visit: