RMX Technologies (Knoxville, TN, US) reports that its atmospheric plasma technology, which it’s been developing for the last four years, is close to commercialization and could reduce oxidation energy consumption during carbon fiber manufacturing by as much as 75%, and overall carbon fiber production costs by 20%.
Rod Grubb, president, and Truman Bonds, vice president of R&D, say they have demonstrated that atmospheric plasma, when used to oxidize polyacrylonitrile (PAN) precursor — instead of the conventional oxidation ovens used today — generates unique reactive chemistry from air that accelerates the oxidation rate.
Bonds notes that conventional ovens requires a great deal of energy and use molecular oxygen in air to thermally and chemically stabilize PAN for the carbonization process. Instead of air and molecular oxygen, the RMX atmospheric plasma system creates “other chemistries,” from air as well as heat, to speed up the oxidation process. “Our system is basically a chemistry generator,” he says.
RMX has proved the technology over the last 18 months using a 1-metric ton/year nameplate capacity oven in its lab. Grubb says RMX has worked with several unidentified carbon fiber manufacturers to test the atmospheric plasma oxidation process and reports that “good product” has resulted. In some cases, he says, properties of carbon fiber made with RMX atmospheric plasma oxidation have exceeded those achieved with conventional thermal oxidation.
Grubb says RMX now has an industrial partnership with an established oxidation oven manufacturer (also unidentified), which will help RMX scale up the technology to a multi-hundred-ton model for commercialization. This, Grubb expects, will happen in the next 18-24 months.
Bonds says the cost and energy savings are achieved primarily because the atmospheric plasma process is faster (20-30 minutes total) than traditional thermal systems. Further, Bonds notes, the RMX oven, as designed, will be one-third to one-half shorter than conventional oxidation ovens, which will help reduce the physical footprint the entire carbon fiber line.
While RMX is scaling up its oven, Bonds says the company will also be working with a European precursor partner to develop a textile-grade PAN precursor specially optimized for plasma oxidation for the manufacture of a 500-ksi, 50K carbon fiber. This effort, Grubb says, could be commercialized around the same time that the oven is.
Although the development work of applying atmospheric plasma to oxidation is about a decade old, most of the effort at RMX on the technology has happened in the last four years. Bonds says the company’s R&D was helped early on by a partnership with Oak Ridge National Laboratories (ORNL, Oak Ridge, TN, US), but that now “we want to emphasize that we are in sole control of commercializing this technology and we want to make sure the marketplace understands that.”
For more information, contact Grubb at firstname.lastname@example.org.
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