|A California startup has received new funding for cracking the puzzle of how to make liquid chemicals directly from methane.
As petroleum prices rise, so does the cost of producing ethylene and all the products that come from it. Ethylene is the world's highest volume commodity chemical and is made from petroleum using "steam cracking" in which the long-chain hydrocarbons are thermally broken down (cracked). Natural gas is definitely cheaper than oil, and with the recent exploitation of shale deposits, particularly in the United States, its supplies are projected to last for decades. Thus, making ethylene from natural gas will provide a far cheaper route to various petrochemicals and even fuels, and could also provide natural gas producers with a valuable outlet for their products, as well as reduce dependence on petroleum. This is why chemical researchers have been searching for years for a way to produce ethylene via anther process.
Startup company Siluria, believes it has found a pathway there using methane instead of petroleum, and has received some US$20 mln in investment capital from various groups to invent technology to convert methane-the main component of natural gas. MIT professor Angela Belcher, a board member of Siluria, has been focusing her research on ways to use methane to make ethylene. She has developed a virus-based template technology that can be used to guide growing nanowire catalysts comprised of inorganic crystals. Afterwards the template can be burned away, leaving just the inorganic surface. The key is that the virus can create a tangle of catalyst coated nanowires that provide so much surface area for chemical reactions to occur that the energy needed to produce the reactions is much reduced. With its hairballs of virus-created nanowires coated with unspecified metals, Siluria has been able to create ethylene-producing reactions at temperatures 200-300 degrees lower than previously achieved. That will provide the perfect platform for discovering the perfect catalyst for replacing oil with methane when making ethylene.
If Siluria is successful-the technology is still confined to laboratory testing-it could transform the economics of producing various chemicals and plastics, and even fuels. It can solve the long evasive problem of finding catalysts that will selectively get methane to react with oxygen to make ethylene. Using recently developed nanotechnology tools and rapidly screening techniques, Siluria says it has invented several groups of catalysts that seem to work, at least in the lab, and is optimizing those catalysts while it continues to search for additional ones. It plans to begin testing the catalysts in a pilot system next year. The company has received additional investment because it now has multiple catalysts that work in a "commercially viable realm" of relatively low temperatures and pressures. The company's candidate catalysts will work with conventional types of reactors and reactor designs, providing manufacturers with a minimal risk of scale-up. New types of reactors will not have to be invented.
The search for more efficient, less expensive approaches to the production of ethylene has gone on for over three decades, and although some progress has been made, no new techniques have yet proved commercially viable. Success in this process will mean lower prices for ethylene and the products that are made from it. Apparently the new process would require less energy and water than current methods, meaning the resultant products would be greener.