US scientists say that they have devised a potentially easier, cheaper and cleaner way to turn natural gas into usable fuels and chemicals – a discovery which could lead to natural gas products displacing oil products in the future.
The process would be less complex than conventional methods to turn natural gas into liquid products and it uses much lower heat and inexpensive materials to get the job done, they said.
High cost prohibitive
Almost anything – fuel or chemical – that can be made from petroleum also can be made from natural gas, but it is not done today because the cost of converting natural gas into those materials is much higher, the researchers said.
"Current technologies to convert natural gas into fuels or commodity chemicals are too expensive to compete with products generated from petroleum," said Roy Periana, director of the Scripps Energy and Materials Centre at the Scripps Research Institute in Florida who led the study published in the journal Science.
The finding comes as natural gas production soars in the United States thanks to methods like hydraulic fracturing, known as fracking, and horizontal drilling. The United States stands as the world's biggest natural gas producer, topping even Russia.
"The US has a glut of natural gas, and there are not that many ways to efficiently use it," said Brigham Young University's Daniel Ess, another of the researchers.
Methane, ethane and propane are the primary components of natural gas. They are members of a class of molecules known as alkanes. But turning alkanes into other useful forms like gasoline and diesel fuel, alcohols or olefins – key sources of industrial chemicals and plastics – can be costly and inefficient with current technologies.
Breaking the bonds
Alkanes are made up of carbon and hydrogen atoms joined together by some of the strongest bonds known in chemistry. Converting these alkanes in natural gas requires the breaking of these bonds which is no easy task.
Conventional conversion methods use very high temperatures – more than 900 degrees Celsius. The method – very much like the original conversion process developed in the 1940s – remains costly, not very efficient and can lead to high emissions of pollutants, the researchers said.
These scientists said their conversion process uses much lower temperatures – about 200 degrees Celsius – and fewer steps. It also uses inexpensive ordinary metals like thallium and lead rather than costly precious metals like platinum, palladium, rhodium or gold, they said.
Their process could greatly reduce capital costs of future processing plants, Periana added.
Periana said the process is not immediately ready for commercialisation and that additional research is required, but that if all goes well a practical demonstration could occur within three years and a pilot plant could be in place perhaps a year after that.
The researchers have been in touch with potential corporate partners and venture capital firms about creating a separate company or collaboration with an existing petrochemical company to commercialise the process, Periana said.
Given vast US and other reserves of natural gas, the new process eventually could help change the world economy from one based on oil to one based on natural gas, Periana said.
"This would lead to a paradigm change in the petrochemical industry, increase energy security and facilitate sustainability, as natural gas is cleaner than petroleum or coal," Periana added.
Like oil, natural gas plays an important geopolitical role.
There are concerns Russia, which has tightened its grip on Ukraine's Crimea peninsula, could slash shipments of natural gas to Europe, nearly half of which go through Ukraine via pipeline.
US House of Representatives Speaker John Boehner and other supporters of American energy exports have seized on the crisis in Ukraine to pressure President Barack Obama's administration to speed approval of liquid natural gas (LNG) exports, saying doing so could help keep Russia in check.
(Picture: natural gas production from Shutterstock)