New material holds great promise for cleaning up wastewater from the oil and gas industry

By Matthew Chin

A groundbreaking membrane material developed at the UCLA Henry Samueli School of Engineering and Applied Science has received an international award for innovation at one of the water industry’s largest global conferences. The new technology holds great promise for cleaning up municipal and industrial wastewaters, in particular, the water that is co-produced during oil and gas extraction. The technology cleans the water to a high level of purity so that it can be safely discharged or reused for beneficial purposes.

Underground oil and gas deposits typically sit on top of a water layer. During the oil and gas extraction process, “produced water” containing varying concentrations of oil and solids is also extracted. The oil and solids in this water must be reduced to very low levels to meet U.S. and international environmental standards. Environmental standards have tightened as reliable clean
water sources around the world have become more scarce, and improved treatment — particularly to enable reuse — of this valuable water resource has become highly desirable. To achieve reuse, most oil and gas producers are turning to ceramic-based membranes because they perform better than conventional technologies and because traditional polymeric membranes are not robust enough for applications as challenging as produced water treatment. However, ceramic membranes are expensive and bulky.

The new polymeric-ceramic membrane, developed by Eric Hoek, professor of civil and environmental engineering, and Richard Kaner, professor of chemistry and biochemistry, and of materials science and engineering, could change that because the materials exhibit ceramic-like performance at the much lower cost of traditional polymeric membranes. The new material’s advantages include resistance to fouling from hydrocarbons, particles and bacteria, as well as tolerance of extreme pH conditions and high temperatures, which makes them easier to clean than traditional polymers.

Because the material is polymer-based, it costs much less to manufacture than ceramic membranes. Finally, the new membrane material is highly “tunable.” That is, the pores that allow water through while keeping pollutants at bay can be made with openings from a few nanometers up to a few hundred nanometers.

Polymeric 2013

Electron microscope image of polymeric-ceramic fibers

This suggests the membrane material can be further engineered for use in a range of water and wastewater treatment applications, including to selectively remove both suspended solids – such as like clay particles and bacteria – as well as dissolved solids which are not typically removed by ceramic membranes.

This suite of advantages earned polymeric-ceramic membranes a Distinction Award for Technology Innovation of the Year at the Global Water Awards, held in Seville, Spain, in late April.

“This innovation is very exciting for me,” Hoek said. “Ric and I have been working on it for over eight years and we have evaluated many applications, but it appears the first commercial use of polymeric-ceramic membranes will be for environmental protection.  That is very satisfying to me.”
Added Kaner: “This is a very exciting new application area for these novel polymers, which were originally developed for applications in aerospace and electronics industries.”

Hoek and Kaner are members of the California NanoSystems Institute (CNSI) at UCLA.

UCLA’s Office of Intellectual Property is in discussions on licensing the technology to Water Planet Engineering, a Los Angeles-based water technology startup.

“We are very excited about the transformative potential for this technology in water purification and recovery and are looking forward to working with industry to get it commercialized, thereby benefitting the economy and society at large,” said Earl Weinstein, associate director of licensing at UCLA’s Office of Intellectual Property.

Water Planet Engineering has been evaluating the UCLA membrane’s performance in produced water treatment. Lee Portillo, who heads up product development and engineering at the company, said, “We have subjected these materials to a battery of tests, really pushing them to their limits. We have tested most commercial membrane materials and, so far, we have not found another polymeric membrane that is better positioned to disrupt the produced water market more than the UCLA polymeric-ceramic membranes. We are now raising a $5 million round of venture funding that will enable Water Planet to commercialize the technology.”

Hoek’s previous membrane innovations have been commercialized through NanoH2O Inc. (nanoh2o.com), a UCLA startup which now sells high performance reverse osmosis membranes around the world.

This latest membrane innovation got its start in 2005 when Hoek, then a junior faculty member, heard Kaner give a talk on new materials his lab was developing. Hoek thought it would be interesting to explore these materials for water treatment membranes.

“I remember sitting in the audience next to a postdoc in my lab, slack jawed as Ric described these amazing materials,” Hoek said. “I turned to my postdoc and said, ‘Imagine if we could get that material into a membrane.’ He then looked at me, slack jawed at first, and then he smiled.  After the talk, I introduced myself to Ric, not sure if such an accomplished chemist and materials scientist would be interested to collaborate with an unknown assistant professor in civil and environmental engineering. Right from the start he was excited to try it, and over the years I have really enjoyed our collaboration.”

Over the past eight-plus years, Kaner and Hoek overcame a number of challenges to be able to create such robust, tunable membranes. One key to their success was exploring methods of modifying the polymer structure and chemistry, and that is the basis for much of the intellectual property they have developed.

Kaner said, “UCLA has a great tradition of collaborations and I’m always looking for ways to put our new materials to use. Working with Eric on membrane technology has been very rewarding.”

Main Image: The new UCLA polymeric membrane has a glass-like surface that repels oil, bacteria and particles.