N-octanol (octaol): colorless liquid. Has a strong aromatic smell. Density 0.83. Refractive index 1.430. Melting point -16℃. Boiling point 196℃. Not miscible with water, but miscible with ethanol, ether and chloroform. Used in making flavors and cosmetics, and as solvents, antifoaming agents, plasticizers, antifreezes, lubricating oil additives, etc.
The production and synthesis method of n-octanol is as follows:
1. Octanol is found in essential oils such as bitter orange, grapefruit, sweet orange, green tea, and violet leaves. It may exist in the free state, or in the form of acetate, butyrate, or isovalerate esters. In industrial production, octanal can be reduced or prepared by utilizing the octanoic acid present in coconut oil. It can also be prepared by oxo synthesis using heptene-1 as raw material. Heptene, carbon monoxide and hydrogen, in the presence of cobalt salt, generate aldehydes at 150-170°C and high pressure of 20-30MPa. After cobalt removal, they are then pressurized and hydrogenated to primary alcohols using a nickel catalyst. This method has mature production technology abroad.
Refining method: fractional distillation under reduced pressure, drying with metallic sodium and then fractionating. Or add boron trioxide to reflux and then distill. The distillate is neutralized with sodium hydroxide and then fractionated.
2. Use industrial product n-octanol as raw material, dry and dehydrate with metallic sodium and then carry out vacuum distillation, or add boron anhydride to reflux and then distill, neutralize the distillate with sodium hydroxide and then reduce it. Pressurize distillation and collect the 98°C fraction at 1333Pa, which is the pure product.
3. Tobacco: FC, 18, 40; synthesis: using methyl octanoate as raw material, reducing with ethanol and metallic sodium; or purifying by fractionation of industrial grade octanol.
4. Preparation method
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