An additional concern with the use of methyl acetate from a vinyl- or ethylene-alcohol or vinyl acetate-based process is the carbonyl content in the stream. Carbonyl impurities include acetaldehyde, acetone, methyl ethyl ketone, butyraldehyde, crotonaldehyde, 2-ethyl crotonaldehyde, and 2-ethyl butyraldehyde and the like, as well as unsaturated aldehydes. Additional impurities to be considered in the methyl acetate stream can include toluene, benzene, acetone, dimethyl acetal, 3-methyl-2-pentanone, propionic acid, ethyl acetate and ethanol.