Gas-phase and liquid-gas-phase nitrilation process

A process for the nitrilation of a fatty acid or of a fatty acid ester to the corresponding nitrile, which is optionally unsaturated, by reacting the fatty acid or fatty acid ester with ammonia in a reactor operating continuously in a gas phase or in a mixed gas-liquid phase in a temperature range of from 180 to 400° C. to produce the corresponding nitrile, in the presence of a solid catalyst comprising:

• at least one metal oxide, the metal of which belongs to column 8 of the periodic table, as a mixture with
• at least one metal oxide selected from the group consisting of aluminum oxides, zirconium oxides, niobium oxides, tantalum oxides and tin oxides,
• the metal oxide(s), the metal of which belongs to column 8 of the periodic table, being present in a volume ratio of 0.1 to 0.6 relative to the volume of the mixture of all the oxides.