The invention is a method of purifying a propylene glycol monoalkyl ether
containing carbonyl impurities which comprises contacting the propylene
glycol monoalkyl ether stream in the liquid phase with a carbon
adsorbent, and recovering a purified propylene glycol monoalkyl ether
product. The purification method improves product quality and reduces the
amount of carbonyl impurities in the propylene glycol monoalkyl ether.