Terrabon achieves production milestone at Texas demo facility

By Bryan Sims | January 27, 2011

Houston-based bioenergy technology firm Terrabon Inc. achieved a significant milestone this week by exceeding its target yield threshold of 70 gallons of renewable cellulosic gasoline from one dry ton of waste feedstock at its demonstration facility in Bryan, Texas.

“Just the research around the process conditions to ultimately achieve that conversion is where a lot of the research in our lab, and translating that into our demonstration plant, has really made this come to fruition,” said Terrabon CEO Gary Luce.

Terrabon’s MixAlco process is described by Luce as a linkage of biological fermentation and chemical processes. It begins by treating the feedstock with lime to enhance its digestibility, and then fermenting the biomass using a mixed-culture of microorganisms to produce a mixture of carboxylic acids. Calcium carbonate is added to the fermentation to neutralize the acids to form corresponding carboxylate salts, which are then dewatered, concentrated, dried and thermally converted to ketones. The ketones are then hydrogenated to alcohols that can be refined into renewable gasoline, diesel or jet fuel blendstocks. 

“When we have those ketones, we use parts of the zeolite and hydrogenation catalysts,” Luce said. “Once we get through the organic acids, we actually create a whole series of secondary alcohols and then we use the same zeolite catalyst structure. The research with CRI that we’ve done is making sure the catalyst structure is set up in a way to optimize through the mix of ketones that we create.”

Terrabon’s cellulosic gasoline product, according to Luce, is a viable drop-in renewable gasoline blendstock that looks similar to cracked gasoline that comes off the fluid catalytic cracking conversion process, a pathway commonly used by today’s petroleum refiners.

“It ends up being a subcomponent of RBOB, which then ethanol can be put on top of to fulfill the RFS2 mandate,” Luce said. “What we’re hoping is that as we begin scaling it up that we can take on the next generation of catalysts to actually make it into a finished product, blend it with ethanol and make E85 straight to the retail station. But, that’s probably version three or four in our vision of what we’re trying to do. First, we want to show we can economically make a drop-in biofuel and use existing infrastructure and satisfy some of this RFS2 mandate.”

Terrabon’s work isn’t satisfied at stopping at this milestone. The company is in the process of engineering scale-up strategies in hopes of bringing its first commercial production plant online. “We’re looking at two regions of the country—one in Texas and another in the Pacific Northwest—to figure out where the best economic position is to put our first commercial facility,” Luce said, adding that the company is targeting an annual production output ranging between 5 MMgy and 25 MMgy. “We’re hoping if we stay on track with what we’re trying to do, then by the end of this year we’ll be breaking ground on either of those two sites for our first commercial facility.”

Luce added that Terrabon intends to leverage existing partnerships with Waste Management Inc. as its core feedstock supply partner, in addition to Valero Energy Corp. for potential off-take arrangements for downstream marketing of its renewable blendstock product once it’s commercially ready.

“We’re not trying to win a Nobel Prize here,” Luce said. “We’re trying to crawl, walk and then run.”