Abstract: A process for the catalytic dehydrogenation of a first unsaturated hydrocarbon to form a second unsaturated hydrocarbon which has one olefinically unsaturated bond more than the first unsaturated hydrocarbon and otherwise an unchanged carbon skeleton, which process comprises: contacting in a first step a feed comprising the first unsaturated hydrocarbon with a first dehydrogenation catalyst having a temperature parameter T1 and a selectivity parameter S1, and contacting in a second step a reaction product of the first step comprising the first unsaturated hydrocarbon and the second unsaturated hydrocarbon with a second dehydrogenation catalyst having a temperature parameter T2 and a selectivity parameter S2, such that T1<T2 and S1<S2.

Abstract: A shaped particle suitable for use as a catalyst support or, alternatively, a dehydrogenation catalyst system in the form of a shaped particle, wherein said shaped particle has a geometry including a length and a cross sectional geometry at at least one point along said length, wherein said cross sectional geometry is defined by an asymmetrical shape having an imaginary dividing line providing for an upper end, having an upper end cross sectional area, and a lower end, having a lower end cross sectional area, wherein said upper end cross sectional area is greater than said lower end cross sectional area. The cross sectional geometry may further be characterized as having a perimeter and as defining a plurality of notches with each said notch of said plurality of notches having a groove depth and a groove opening rotational distance.