As the primary component of natural gas, methane is a common, problematic by product of oil drilling.
A greenhouse gas 34 times more potent than carbon dioxide over the course of a century, methane is a costly challenge for the energy industry. Piping it from remote areas is expensive, so companies burn off about a third of the gas they produce in bright flares that can be seen from space.
In 2015, a team of Russian and US scientists claimed that this methane gas flaring accounted for 3.5% of the world’s natural gas consumption. Every year, methane burnt off by oil and gas fields produces as much greenhouse gas as a million cars.
A cheap, less polluting solution
Two scientists from Washington State University, Jean-Sabin McEwen and Su Ha, have been working on developing an alternative to methane flaring.
"It's a big problem because not only do you waste energy, but you produce CO2," says Ha, a Washington State University associate professor of chemical engineering and director of the O.H. Reaugh Laboratory for Oil and Gas Research. "So the question is: Is there something you can do better than that?"
Usually, methane is such a tightly bonded molecule that huge quantities of water and extremely high temperatures (1,800°F/982°C) are needed to break it down. McEwen and Ha discovered that lower operating temperatures and an inexpensive nickel catalyst could be used in the presence of an electrical field to orientate methane and water in a way that makes them easier to break apart.
"It's like a combination lock," said Ha. "When you apply the right combination, when you apply the electric field with the right strength and right direction, it's like you are applying a combination to a lock and click, it opens."
Carbon monoxide and hydrogen are the products of the process, ingredients that can be used to generate synthetic gas (syngas). This syngas can be used to produce gasoline, or the reactor could be attached to fuel cells that convert and store the energy as electricity.
"The idea is to have something that is better suited to these remote areas than a large-scale reactor," said McEwen.
A study detailing McEwen and Ha’s research has been published in the journal ACS Catalysis.