Distribution of butyric acid between water and trioctylamine dissolved in 17 solvents (isoamyl alcohol, 1-nonanol, 1-decanol, 1-dodecanol, oleyl alcohol, methyl ethyl ketone, isopropyl methyl ketone, isobutyl methyl ketone, 4-heptanone, ethyl acetate, cyclohexyl acetate, dimethyl phthalate, dibutyl phthalate, tert-butyl methyl ether, kerosene, n-hexane, toluene) and 4 vegetable oils (haselnut, corn, soybean, olive) have been studied at T) 298.15 K. The highest distribution coefficient for butyric acid is shown by trioctylamine dissolved in isoamyl alcohol. As the molar mass of the alcohol increases, the value of the distribution coefficient decreases. In the amine extraction, it was observed that the use of trioctylamine dissolved in alcohol increased the distribution coefficient between 6 and 7 times; dissolving in ketones increased the distribution between 3 and 5 times; dissolving in esters increased it 4 to 9 times; dissolving in tert-butyl methyl ether increased it 2.3 times; dissolving in hydrocarbons increased it 10 to 18 times; and dissolving in vegetable oils increased it 12.5 times, all as compared to use of the pure solvents as extractant.