In first thank you for your time, i've some problems with the implementation in HYSYS program (in the institute where i'm doing my licence degree) about a separation process to produce Ethylene Oxide 99.5% of purity, from gaseous reactor effluent produced by Shell Oil reaction process.
The desired Ethylene Oxide product stream should have, at least, the conditions presented in the next table.

Stream                  Feed              Product
temp(ºC)                 250                 46.32
pressure(bar)            16.6                 3.5
Ethylene Oxide           366.60               362.04
Acetaldehyde             0.47                 0.10
water                    321.36               0.60
formaldehyde             1.15                 <0.001
argon                    175.18               0
nitrogen                 60.21                0
methane                  5 974.7              trace
ethylene                 3 074.4              <0.001
CO2                      894.47               <0.001
oxygen                   476.82               0
ethane                   262.19               0.001

thanks for your help,
best regards

Hélio Carvalho