Aromatic loop, simplified balance

The production schemes shown in Section 4.1 may comprise an aromatic loop to tnaTtmigg the production of o- and p xylene at tiie expense of jii xylene. The two variants in Fig. 4.2 are resumed in Figs. 4.26a and 4.26b, which show only the units of the aromatic loop. This loop may or may not be preceded by ethylbenzene separation, as required. 

Xq s per cent weight o xylene, s per cent weight p-xyiene,.  

Po O Xylene yield of the distillation operation this parameter depends essentially on the QoiQp ratio and is calculated by balance. 

The writing can be simplified by consideriog the reduced recycle amouot r, itself divided into two parts  

The xylene isomerization yidd is 97 per cent, die remaind being cracked with the formation of lighter products (benzene gas). 

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