Examples of application from laboratory practice

With the aid of the columns and other apparatus described it is possible to separate liquid mixtures continuously at normal and reduced pressures as well as at small overpressures (chap. 5.4.5) as sharply a.s in batch distillation. This is clear from the distillation curves of the products obtained in the continuous distillation of a mixture of crude fatty acids in the C4 to Ci range (Fig. 168). A further example shows that by the use of control devices it was possible to separate a mixture of phenols into its main components with great constancy. Fig. 169 illustrates the results of the first separation in this sequence, which was made between the ortho- and Twcfa/pom-cresol fractions. 

120 samples were taken during the run for determination of the density of the bottoms and the solidification point of the tops. As the diagram shows, there were negligible variations in the temperatures of the feed, the head and the bottom, and 

Distillation curves of products prepared by continuous laboratory distillation from a Cj—Ck mixture of fatty acids 

Continuous rectification of crude phenols. Pressure SOtorr duration of run 22 hours 

Distillate phenol -j- o-cresolj bottoms ra/p-cresol -f- xylenols and higher 

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