Emulsifier and catalyst performance optimization for ethylene epoxidation

A process for maximizing the selectivity (S) of an epoxidation catalyst in an ethylene oxide reactor system, the process comprising: receiving a measured reactor selectivity (Smeas), a measured reactor temperature (Tmeas), and one or more operating parameters from an ethylene oxide production system, the ethylene oxide production system is configured to convert a feed gas comprising ethylene and oxygen to ethylene oxide in the ethylene oxide reactor system in the presence of the epoxidation catalyst and a chloride-containing catalyst moderator. The epoxidation catalyst comprises silver and a promoting amount of rhenium (Re), and the measured reactor selectivity (Smeas), the measured reactor temperature (Tmeas), and the one or more operating parameters include real-time and historical operating data points over time generated by the ethylene oxide production system. The method further includes using the processor to perform the following steps: (a) for each point in time, using the model to calculate a model-e