METHOD OF PURIFYING SULFATE PINE OIL-CONTAINING PRODUCT Russian patent published in 1997 - IPC

FIELD: wood working industry. SUBSTANCE: in a method involving preliminarily treating initial material with aqueous alkali solution followed by separation of water-alkali layer from organic layer and treatment of the latter with mineral sorbent, initial material is sulfate terpentine or sulfate α-pinene. Preliminary treatment is performed with 6-12% alkali solution in amount 1-5% based on initial terpentine or α-pinene weight at temperature 70-105 C for 60 to 240 min. Organic layer is treated with sorbent immediately after separation and treated organic layer is then submitted to vacuum distillation. As sorbent, product is used obtained by hydrating titanium dioxide with 20-30% alkali solution and subsequent decomposition of resulting titanate with organic acid. Sorbent is applied in concentration 0.1- 1.0% based on weight of initial terpentine or α-pinene. Utilized are: NaOH or KOH (alkali), hydrochloric or sulfuric acid (mineral acid), and formic or acetic acid (organic acid). Organic layer may be additionally treated with another sorbent: activated carbon taken in amount 0.1-0.4%. Percentage of residual sulfur in treated product is as low as 0.0005%. EFFECT: increased yield and improved quality due to reduced total sulfur in treated product and reduced number of treatment operations. 4 cl