Process for producing high purity isobutene by combining reactive distillation with hydrogenation isomerization, distillation and skeletal isomerization

摘要

The present invention relates to a process for the preparation of high purity isobutene from hydrocarbon classifications comprising isobutene and also C ₄ olefinic hydrocarbons per molecule, including butene-1 and butene-2 compounds in proportions corresponding to nearly thermodynamic equilibrium. . This method passes a fractionate through a distillation zone 3 connected to a hydroisomerization reaction zone and passes the bottom product of the distillation zone containing the butene-2 compound into a second distillation zone 4, preferably extraction. Passing through the distillation zone produces a first effluent comprising mostly butene-2 compounds and a second effluent comprising mostly n-butane and passing most of the first effluent into the skeletal isomerization reaction zone (2) Wherein the linear butene is at least partially isomerized with isobutene and at least a portion of the effluent from the skeletal isomerization zone is recycled upstream of the reactive distillation zone 1.