Mechanical Engineering Associate Professor Neal Sullivan and Metallurgical and Materials Engineering Professor Ryan O’Hayre were recently awarded close to $330,000 from the U.S. Department of Energy to upgrade natural gas to building-block fuels using a novel, scalable reactor.
In this two-year small business innovative research (SBIR) program titled “Methane Dehydroaromatization with Protonic Ceramics,” Sullivan and O’Hayre will work with Technology Holding LLC of West Valley City, Utah, to demonstrate a modular and scalable reactor that economically upgrades natural gas into fuels and chemicals. The novel approach integrates carbon-carbon catalysts developed at Technology Holding with protonic-conducting ceramic membranes developed at Colorado School of Mines to efficiently convert the methane from natural gas into benzene, a building-block fuel used to produce numerous valuable chemicals.
Benzene is currently made in large chemical plants from crude oil. If the new technology proposed in this SBIR program is successful in converting methane to benzene, it could create opportunities to harness our nation’s vast natural gas resources to fuel the transportation sector and other petroleum-based industries. This would decrease our dependence on crude oil and move transportation toward more sustainable fuels.
“We don’t have a good technology to cost-effectively convert natural gas to benzene,” Sullivan says. “With current processes, the natural gas conversion is low, the benzene formation is low, and the catalysts get gunked up fast. By harnessing emerging materials developed at Mines with advanced catalysts from our industrial partner Technology Holding, we can increase reactor productivity, boost natural gas conversion, and promote benzene formation.”
The proposed modular approach and small reactor footprint enables placement and use of the new technology at remote natural gas wellheads.
“If we can make benzene from natural gas, especially the ‘stranded’ gas that is far from a processing plant, we’ve got a way to stop the flaring of stranded natural gas, which reduces greenhouse gas emissions while creating a valuable chemical,” Sullivan says.
The figure illustrates the proposed concept for electrochemical methane dehydroaromatization (E-MDA). A tubular membrane reactor with an aluminosilicate zeolite ZSM-5 catalyst (blue) surrounds a proton-conducting ceramic membrane (red) with porous support. Methane (CH4) is fed to the catalyst, forming benzene (C6H6) and hydrogen (H2). The hydrogen is split to form protons (H+) that are driven across the protonic membrane, effectively removing the molecular-hydrogen product from the reaction zone. This product removal shifts the equilibrium chemistry, resulting in greater methane conversion and benzene formation, promoting the natural-gas-to-liquids process.
This program builds on active research programs in the Colorado Fuel Cell Center (cfcc.mines.edu) involving proton-conducting ceramic electrochemical devices. Through years of careful technical advancements, these emerging materials are now finding applications in electricity generation and energy storage, and through this new program are being extended to the field of fuels synthesis.