The search for greener ethylene

Abstract

One of the pillars holding up the chemical industry rests on shaky ground. That pillar, ethylene, is arguably the most important petrochemical raw material. Its handy carbon-carbon double bond is easily opened and made accessible for countless chemical reactions. For instance, free-radical polymerization of ethylene creates the molecule’s largest-volume derivative, polyethylene, which is used in plastic bags and packaging. The reaction of ethylene with chlorine produces ethylene dichloride, a precursor to another plastic, polyvinyl chloride. Combined with oxygen, ethylene becomes ethylene oxide for detergents and ethylene glycol. But forming that convenient double bond uses a lot of energy. Cracking the hydrogens off an ethane molecule or longer hydrocarbons like naphtha requires temperatures in excess of 800 °C. And the heat for the enormous furnaces where cracking takes place comes from combustion of natural gas or other fossil fuels. According to EcoCatalytic, which is developing an alternative route to ethylene, conventional