Production of o- and p-xylenes, variant

The difference between these two variants is related to the separation of o-xylene, which takes place on a smaller feed, but with a higher yield. This variant is espedally interesting if the demand for o-xyiene is much smaller than the demand for p-xylene Thus a maximum of o-xylene can be isomerized to p-xylene, with only a part of the isomerization effluent sent for distillation. 

Remark. The foregoing calculations are valid for situations normally encountered, in which demand for p-xylene is greater than for o-xylene. If not, the value of po obtained may be higher than 1. A technically feasible maximum value of p is therefore set, and the value of pf that helps to adjust the balance is calculated. Low values of Pq or pp may correspond to low yield operation, or to the diversion of part of the effluent, which therefore does not go to the separation unit 

Free addity None None None None 

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