Ethylene oxide (C2H4O) is formed by the partial oxidation of ethylene in a gas phase reaction. In this process, 1000 mol/h of pure ethylene is fed to the system. It is mixed with air. The feed rate of the air is such that the molar ratio of ethylene in the fresh feed to oxygen is 2:1. The ethylene single-pass conversion is 25%. The stream leaving the reactor contains ethylene, ethylene oxide, water, CO2, and N2 only; all of the oxygen is consumed. The reactor effluent goes to a separation unit in which the ethylene and nitrogen are separated from the other gases. A portion of the ethylene and nitrogen stream is purged, and the.

remainder is mixed with the fresh ethylene and air streams to form the reactor feed. The remaining gases (ethylene oxide, water, and CO2) are sent to other units for further processing. A total of 50 mol/h of CO2 appears in this stream. The gas phase reaction proceeds accord- ing to the following stoichiometry:

C 2 H 4 + 12 O 2 → C 2 H 4 O

C2H4 +3O2 →2H2O+2CO2

Determine the amount of ethylene oxide is produced (Problem

Figure 6.9.1). (850 mol/h)

  

CH;OH HCHO + H, 1 H2 +02 H2O 8) Purge CH4 N2 C,H: 1000 mol/h Y-3 Reactor Air: (21%O, 79%N,) CO, = 50 mol/h CH,0 Separator