Dehydrodimerization of Isobutene to 2,5‐Dimethyl‐1,5‐Hexadiene over Bismuth‐(III)‐Oxide and Various Additives

Bi₂O₃ and mixtures with different additives (Cr₂O₃, MoO₃, NH₄VO₃, SnO₂, and V₂O₅) have been chosen to study the oxidative dehydrodimerization of isobutene. The catalytic performances were investigated by variation of the residence time, isobutene to oxygen molar ratio, and pressure. The best results for 2,5‐dimethyl‐1,5‐hexadiene (DMH) yield (13 %) were achieved with Bi₂O₃ as the catalyst. The selectivity of DMH reaches values of over 90 %.