Extraction of Chinese fir wood oil and refinement of pyroligneous oil

With the steam distillation method, high quality of Chinese fir oil could be obtained, but low yield of 1.7%. With the retorting method, yield of the crude pyroligneous oil was as high as 9.6%, but its quality was poor and the oil could not be directly used in the perfumery.In order to improve the quality and yield of Chinese fir oil, the Chinese fir oil was extracted from Chinese fir root by the steam distilling and retorting methods. The purification process of the crude pyroligneous oil was also studied, which focusing on the radical substitution reaction in the presence of the peroxide and the fatty alcohol and the influence of the reacting condition on the smell of the pyrolysis oil, and suitable technological conditions of reaction temperature and time (140℃ and 1h) were obtained. The chemical constituents and relative contents of the steam distillation oil, the crude pyroligneous oil and the refined pyroligneous essential oil were characterized by GC-MS with 26, 50 and 34 compounds respectively. Among all of the chemical constituents, the main components contained α-Cedrene, β- Cedrene, Cedro, Thujopsene, etc., which were the characteristic aroma constituent for cedarwood oil. The composition among the crude pyroligneous oi was complex, and many carboxylic acids, phenols and α, β-unsaturated carbonyl compounds which influenced the the pyroligneous oil aroma were removed by refining process. The result showed that the refined pyroligneous essential oil had light color, soft wood and tree fragrance, which may be used as a perfume raw material in the perfume industry.