Patent ID: 6111160
Filing Date: 2000-08-29
Classification: B01J,C07C

Abstract:
A method for the structural isomerization of linear olefins selected from the group consisting of linear C.sub.4 -olefins, linear C.sub.5 -olefins, and mixtures thereof in the presence of contaminant diolefins to corresponding isoolefins of the same carbon number which comprises(a) contacting an organic feedstock containing linear olefins selected from the group consisting of linear C.sub.4 -olefins, linear C.sub.5 -olefins, and mixtures thereof with a catalyst comprising a member selected from the group consisting of H-ferrierite and the hydrogen form of ZSM-35; and(b) under structural isomerization conditions wherein said conversion is carried out at:(1) temperatures between 250.degree. C. and 650.degree. C.;(2) weight hourly space velocities (WHSV) based on linear C.sub.4 -C.sub.5 -olefins in said feedstock between about 1.0 and about 50 WHSV;(3) linear C.sub.4 -C.sub.5 -olefin partial pressures from about 0.5 atm. to about 10 atm.; and(4) in the presence of hydrogen added in an amount sufficient to enhance linear C.sub.4 -C.sub.5 -olefin conversion and extend the catalyst life of the catalyst relative to operation without any hydrogen added.