Isolation of Benzene, Toluene and Xylene Cont.....

Solvent recovery column:

•          To separate non-aromatics and residual carried over solvent contents, solvent recovery column is used. Top vapours of the extractive distillation column injected to the location below pall rings packing of the solvent recovery column.
•            N-formylmoropholine (NFM)  recovered at the bottom of the column is returned to the extractive distillation column. The purpose of the solvent recovery column is to eliminate the loss of NFM losses.
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•          The difference between normal distillation and extractive distillation column is based on phase separation in the separator at the bottom section. Non-aromatic compounds are separated to the bottom of the column with a two-phase product.

Following parameters are set during the process:

•Packing                         Pall rings

•Bottom pressure         0.25 kg/cm2

•Top pressure                0.2 kg/cm2

•Top temperature         100оC

•Bottom temperature    125оC