abstract |
Process for producing acetic acid are disclosed in which a vapor sidedraw is withdrawn from the second column in the primary purification train. The vapor sidedraw comprises acetic acid and lithium-containing compounds at a concentration of no more than 100 wppb. A bottoms stream that is enriched in lithium-containing compounds, such as lithium acetate, or lithium acetate dihydrate, is also withdrawn from the second column. Advantageously, the vapor sidedraw, or a condensed portion thereof, is directly fed to a metal-exchanged ion exchange resin having acid cation exchange sites to produce purified acetic acid. This prevents displacement of the metals in the ion exchange resin. |