METHOD FOR ISOMERIZATION OF BRANCHED UNSATURATED MONONITRILES INTO LINEAR UNSATURATED MONONITRILES

摘要

The invention concerns a method for isomerization of branched mononitriles comprising an ethylenic bond into linear mononitriles. More particularly, the invention concerns performing said isomerization reaction in gas phase and in the presence of a heterogeneous catalyst. Therefor, the invention proposes isomerization of aliphatic and acyclic branched mononitriles comprising an ethylenic unsaturation non conjugated with the nitrile function into linear mononitriles by heating at a temperature less than 170 DEG C and higher than the saturated liquid temperature of the mononitriles in the presence of a catalyst comprising a transition metal in oxidation state 0 or 1 and a ligand consisting of a multidentate phosphine. The inventive method is particularly useful for making adiponitrile from butadiene.