Preparation of pine flotation oil by hydration with α-pinene

Abstract

The hydration of α-pinene of gum turpentine and separately pinene fractions in the organic acids media for the purpose of obtaining terpene alcohols, which are widely used as flotation reagent for mineral processing in mining production were studied. The best results are obtained among the organic acids when 70% formic acid is used. The α-pinene hydration process in the acid imedium is exothermic, and it is necessary to maintain a constant temperature of 65 °C to reduce the rate of side reactions. The main component of turpentine, resulting in the formation of α-terpineol is α-pinene; 3-carene, terpinolene, and limonene contents do not practically change in the reaction mixture, which testify their stability in 70% formic acid media. The maximum content of terpene alcohols (60,1%) was obtained when using α-pinene fraction at a ratio of α-pinene and 70% formic acid 1.0 : 1.1 for 3 hours. Increase of the duration of hydration reaction leads to the decrease in the content of terpineol in the reactio n mixture due to the secondary isomerization processes.