Good news! However, this is a theoretical study!
"Scientists have discovered a potentially greener way to produce a crucial industrial chemical used to make many everyday products from plastics and textiles to antifreeze and disinfectants ..."
"... 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. ...
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. ..."
"... The team has submitted international patents for its discovery and is in discussions with a major commercial producer about implementing the technology in existing manufacturing facilities. ..."
From the editor's summary and abstract:
"Editor’s summary
Traces of nickel can increase the selectivity of supported silver ethylene epoxidation catalysts to levels comparable to that of added alkyl chloride promoters. Theoretical studies ... showed that nickel dopants on silver could activate molecular oxygen, and surface science experiments showed that nickel could stabilize nucleophilic oxygen that would otherwise react unselectively. Parts per million addition of nickel enhanced selectivity by 25%, and added chlorine could also boost the effect of nickel by an additional 10%. ..."
Abstract
Over the last 80 years, chlorine (Cl) has been the primary promoter of the ethylene epoxidation reaction valued at ~40 billion USD per year, providing a ~25% selectivity increase over unpromoted silver (Ag) (~55%). Promoters such as cesium, rhenium, and molybdenum each add a few percent of selectivity enhancements to achieve 90% overall, but their codependence on Cl makes optimizing and understanding their function complex.
We took a theory-guided, single-atom alloy approach to identify nickel (Ni) as a dopant in Ag that can facilitate selective oxidation by activating molecular oxygen (O2) without binding oxygen (O) too strongly. Surface science experiments confirmed the facile adsorption/desorption of O2 on NiAg, as well as demonstrating that Ni serves to stabilize unselective nucleophilic oxygen. Supported Ag catalyst studies revealed that the addition of Ni in a 1:200 Ni to Ag atomic ratio provides a ~25% selectivity increase without the need for Cl co-flow and acts cooperatively with Cl, resulting in a further 10% initial increase in selectivity.
Engineers find greener path to making key industrial chemical (original news release)
Nickel promotes selective ethylene epoxidation on silver (no public access)
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