Abstract: The comparison of isolation methods of dehydroabietic acid was carried out, using disproportionated rosin as raw material by GC method. Dehydroabietic acid was isolated from disproportionated rosin by methods of amination, saponification and aminating reaction-crystallization enhanced with ultrasonic wave, respectively. The isolating dehydroabietic acid from diffe-rent kinds of disproportionated rosins has been investigated. The results showed that the method of aminating reaction-crystallization enhanced with ultrasonic wave was the best to isolate the dehydroabietic acid from the self-made disproportionated rosin at the temperature of 40℃. The purity of dehydroabietic acid prepared was 99.99%. The yield of dehydroabietic acid was 55.37%. The high purity dehydroabietic acid prepared has been analyzed and confirmed by using GC, UV, IR, melting point instrument and polarimeter as well. The results are in agreement with the values in literature.

Key words: dehydroabietic acid, isolation, disproportionated rosin