Imma Perfetto
Cosmos science journalist
Chemical engineers have discovered a greener way to make an industrial chemical used to produce many everyday products – from plastics and textiles to antifreeze and disinfectants.
The manufacture of ethylene oxide is estimated to be a US$40 billion per year global market. But its current production process requires the use of toxic chlorine gas, lots of energy, and releases the highest carbon dioxide emissions per volume compared to other high-value chemicals.
In a new study in the journal Science, researchers have demonstrated that adding small amounts of nickel to silver catalysts can do away with chlorine while maintaining production efficiencies for industrial-scale production.
Ethylene oxide (C2H4O) is created through the reaction of ethylene (C2H4) and oxygen in the presence of a silver catalyst, which reduces the energy required for the process.
However, this also produces carbon dioxide as a by-product.
Adding chlorine to the mix improves the efficiency of conventional ethylene oxide production by about 25%. But it is a corrosive chemical and has safety issues and environmental impacts.
The new study found that adding just one atom of nickel for every 200 silver atoms in the catalyst resulted in the same 25% improvement.
“If industry does try this out and find it useful and are able to commercialise it, the twin benefits are you can save a lot of CO2 and a lot of money,” says Matthew Montemore, a chemical engineer at Tulane University in the US and co-author of the study.
The team has submitted international patents for their discovery and is in discussions with a major commercial producer about implementing the technology in existing manufacturing facilities.
