Process for the recovery of pure acetone from cumene hydroperoxide cleavage reaction product.

摘要

Pure acetone is recovered from a crude acetone vapour fraction removed overhead from a first column separating phenol and higher boilers as a bottom fraction from a cumene hydroperoxide cleavage reaction product by partially condensing the crude acetone fraction, returning the condensed portion of the crude acetone fraction to the first column as reflux, feeding the remaining portion as a vapour to an intermediate point in a second distillation column to which there is also fed continuously at a point above the acetone feedpoint a dilute aqueous solution of an alkali, removing from the base of the second column a residue fraction comprising compounds boiling above acetone, removing from a point in the second column intermediate between the alkali feedpoint and the top of the column as a liquid sidedraw fraction pure acetone having a permanganate time (PT) greater than 4 hours, and removing from the top of the second column as a vapour fraction acetone having a PT less than that of the sidedraw fraction, condensing the acetone vapour fraction and returning to the second column at a point above the liquid acetone sidedraw removal point a portion of the condensate as reflux.