Going Beyond Silver in Ethylene Epoxidation with First-Principles Catalyst Screening.

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• Ethylene epoxidation is a critical industrial selective oxidation process.
• Silver catalysts are the established standard, with ongoing improvements through empirical doping and co-catalyst discovery.

Purpose of the Study:

• To computationally screen the periodic table for superior ethylene epoxidation catalysts.
• To experimentally validate computationally identified catalysts.
• To emphasize the importance of in situ conditions in computational catalyst design.

Main Methods:

• Computational screening of metals using ab initio calculations.
• Experimental synthesis and testing of novel catalyst formulations.
• Rigorous reactor microkinetic modeling incorporating surface oxidation and side reactions.

Main Results:

• Ag/CuPb, Ag/CuCd, and Ag/CuTl catalysts demonstrated superior performance compared to pure silver.
• Computational models that include in situ conditions accurately predict experimental outcomes.
• Neglecting in situ effects like surface oxidation leads to erroneous catalyst predictions.

Conclusions:

• Computationally-led catalyst design, incorporating in situ conditions, can accelerate the discovery of superior catalysts for industrial applications.
• The developed microkinetic modeling approach bridges the gap between first-principles simulations and practical catalyst development.
• The methodology is extensible to larger reaction networks and additional complex effects like surface oxidation.