In one of our news “roundups” posted last week, there was a brief mention of NSF support for work being done on a family of organically-modifiable silica products that is being developed under the Osorb brand name. I think it is worth taking a little deeper look at this material and what it could do, given the growth of new gas drilling/fracking projects in the US and the concerns about the environmental impact.
According to its principle developer, Paul Edmiston, somewhat stumbled into discovering what the material could do. An NSF story quotes Edmiston, saying, “The discovery of Osorb was serendipitous. It happened during basic science research, while I was investigating glasses that would bind with explosive vapors.”
An NSF story reports that Edmiston, chair of the analytical chemistry department at Wooster College (a small Ohio institution) had been focusing on detector-type applications based on nano-engineered glass
His lab is composed of exclusively undergraduate students who were testing various methods of preparation at the time. During testing, one of the formulations instantaneously grew in size. That formulation became the first identified member of a now larger group of swellable silica-based materials. (emphasis added)
In other words, the Osorb key properties depend on mechanical and dimensional changes. Edmiston explains in the same NSF story
“So, when Osorb expands and is absorbing something, it is not going through a traditional chemical reaction. Osorb is actually going through a mechanical expansion, sort of like the sponge in your kitchen, a nano-mechanical sponge.”
One big plus is that this “nano-mechanical sponge” repels water, and its structure and composition can be tuned to optimize its ability to suck up particular contaminants in water. Early on, Edmiston discovered that the Osorb is particularly talented at sucking oily materials out of water.
Edmiston has working for several years with ABSMaterials to commercialize and adapt Osorb for a variety of applications. For example, ABSMaterials Osorb-based VOCEater system can remove volatile organic compounds, including chlorinated solvents, pesticides, herbicides and even pharmaceuticals. Apparently there are around 30 Osorb variations developed so far.
Another big plus is that Osorb is relatively simple to make and can be reused repeatedly (the filtered compounds can be removed and captured through heating or chemical rinsing, followed by decompression). The essential ingredients are acetone, glass particles and a catalyst. When combined, they form a gel, which is then dried. Unlike aerogel creation—where maintenance of the 3D structure is critical during drying—Osorb gel drying is allowed to reduce the bulk to one-eighth its original size. It can also lift 20,000 times its own mass.
Edmiston and ABSMaterials have been working on projects involving cleaning municipal water supplies and stormwater runoff and, so far, they say they have been able to cost-effectively scale-up the production and use of the Osorb.
Municipal water treatment is a huge market, but so is energy production, and that brings us back to the issue of gas production and tracking. Many individuals and communities have expressed concern because drilling and fracking produce a lot of contaminated water, either because it is pumped in or because it is released from subsurface sources. Meanwhile, energy producers and the government have a long-term interest in seeing that underground gas and petrochemical resources are tapped. Everyone would like to see something like Osorb succeed.
According to a story from this summer in the New York Times, Edmiston and ABSMaterials have been working using a 2011 SBIR grant to develop materials and systems for energy prospectors and have been making headway. NSF reports on its website that a version of Osorb can remove 90 percent of the organic compounds found from fracking wastewater, and have expanded their efforts to tune the porous glass to suck up radioactive elements and rare earth metals. A trailer-mounted prototype can process 60 gallons of water per minute.
Perhaps Osorb won’t pan out, and oftentimes these descriptions turn out to be too-good-to-be-true. But something like it is certainly needed. While several recent examples of water contamination have been duly covered in the media, it is important to note that drilling and wastewater can turn into a huge, long-term liability for taxpayers. Boreholes are forever—but ownership and accountability isn’t. The Midwest is riddled with hundreds of thousands of old, nonproductive sites left over from prior drilling booms. Very often these wells have not been properly capped or the caps have been damaged, and, as a result, can unexpectedly spew “brine” and toxic water-borne contaminants that require considerable remediation.
For example, West Virginia has over 110,000 wells; 13,000 are classified as “abandoned” and state officials can’t identify who last operated 5,800 of these. Pennsylvania may have 200,000 abandoned wells. In Ohio, Wood County, alone, is reported to have 36,000 abandoned wells, some of which have been leaking into aquifers, and state officials estimate that only 1-2 percent of all of Ohio’s old wells have been properly capped. Unfortunately, cash-strapped state officials show little inclination or ability to fix these problematic sites, some dating back more than 100 years.
So, the problem of contaminated drilling-related water isn’t a new one. But if an inexpensive and scalable product, such as Osorb, comes along, it will arm state regulatory officials with something powerful it can demand to be used as part of the governmental permitting process.
Meanwhile, here is a longer NSF-produced video demonstration of Osorb and an interview with Edmiston: