Can New Catalysts Turn the Corner for Methanol?

The concept of converting our abundant natural gas supplies into liquid methanol in order to replace oil in our gas tanks has had trouble gaining traction for several reasons, all of which are about to face change.

The first reason is that most of the attention towards additives has been focused on ethanol made from corn. Driven by highly specific government mandates, corn ethanol — which now consumes 45 percent of the country’s corn crop — has taken up whatever role industrial methanol might have been chosen to play as a gasoline additive.

Secondly, there’s the problem of the Environmental Protection Agency. Not only has the EPA not approved methanol for gas tanks, the organization actually imposes huge fines on anyone who converts a gasoline engine to methanol without its permission.

The third, and less distinguishable explanation for methanol’s difficult implementation, is that the whole idea has never been very sexy. Methanol has little to do with the “Cutting Edge” or the “New Age Economy.” The manufacturing of methanol is a 60-year-old process practiced doggedly by dozens of industrial facilities around the world. They produce 33 billion gallons a year at the reasonable price of $1.50 per gallon; the energy equivalent of $2.35 gas. Meanwhile, Elon Musk seems to announce a new milestone for the Tesla, or some “breakthrough” in battery technology or cellulosic ethanol emerging from the university laboratories each week, making methanol appear rather plain-Jane and old fashioned. In effect, the solution to our gas tank woes has been hiding before us in plain sight.

Now an announcement from the Scripps Howard Research Institute and Brigham Young University may change everything. In a paper published last week in Science, a team led by Roy Periana of the Scripps Florida Center and Professor Daniel Ess of Brigham Young University say they have found catalysts made from the common elements of lead and thallium that facilitate the conversion of gaseous methane to liquid methanol, potentially making the process even cheaper and more accessible.

The hydrogen bonds in the alkanes (methane, ethane, propane, etc) are among the strongest in nature. To break them involves a heat-driven process invented in the 1940s that is conducted at 900 degrees Celsius. For more than two decades, the Scripps team has been looking for catalysts that would shorten this heat requirement. In the 1990s they came up with a series of catalysts employing platinum, palladium, rhodium and gold, but quickly realized that these elements were too rare and expensive for commercial application. So it was back to the drawing boards in search of something more useful.

Last week in Science they reported success:

The electrophilic main-group cations thallium and lead stoichiometrically oxidize methane, ethane, and propane, separately or as a one-pot mixture, to corresponding alcohol esters in trifluoroacetic acid solvent.
The process reduces the heat requirement to only 200 degrees Celsius, which introduces enormous potential for energy savings. That “one-pot” notation is also crucial. Methane, ethane and propane all come out of the Earth together in natural gas. Currently, they must be separated before the heat-driven process can begin, With the new catalysts, no separation will be necessary. This means that methanol could become significantly cheaper to harvest than it already is. More importantly, these findings signify that methanol conversion will be able to weather the inevitable price increases that will result as demand for natural gas supplies multiplies.

Periana says the process is three years from commercialization. Reports Chemical & Engineering News:
The team is in discussion with several companies and entrepreneurs and would ideally like to jointly develop the technology with a petrochemical company or spin off a startup.

Periana also claims that “Initial targets would be higher-value, lower-volume commodity chemicals such as propylene glycol or isopropyl alcohol directly from propane.” He told reporter Stephen Ritter:

The next target could be to develop lower-temperature processes for higher-volume chemicals, such as converting methane to methanol and ethane to ethanol or ethylene as inexpensive sources for fuels and plastics.

An enormous portion of the world’s energy consumption is still tethered to oil, particularly the transportation sector, where oil constitutes 80 percent of consumption. As oil becomes more and more difficult to find, natural gas use is escalating. In addition, 25 percent of the world’s gas is still flared off because it has been uneconomical to capture. All this could change rapidly if a low-cost conversion to methanol becomes a reality. Reuters grasped the implications of this development when it reported that the new catalytic processes “could lead to natural gas products displacing oil products in the future.”