Modification and purification of rosin

Abstract

The aim of this research was to modify and purify rosin by dehydrogenation (disproportionation), and hydrogenation reactions. Dehydrogenation was to operate in a temperature range of 240-280°C under nitrogen atmosphere and concentration of Pd/C catalyst 0.3% by weight of rosin for 4 hours. Dehydrogenated rosin was distilled under reduced pressure of 3 mmHg in an atmosphere of nitrogen to obtain 87% yield of purified rosin. The purified rosin was crystallized from acetone to obtain 97% of dehydroabietic acid having a melting point 160℃. Hydrogenation was to operate at optimum condition using Raney Nickel catalyst at 200℃, 12 hours, 700 psi, 10% catalyst concentration by weight of rosin and in ethanol. Hydrogenated rosin was distilled under reduced pressure of 3 mmHg to give pure hydrogenated rosin (86.23%).