Patent ID: 6897345

Claim:
The process for the production of hydrocarbons with a high octane number starting from a mixture comprising n-butane and isobutane, comprising: a) feeding a part of the mixture comprising n-butane and isobutane a stream of hydrogen and a stream consisting of recycled n-butane, to a skeleton isomerization section, wherein said n-butane is isomerized; b) joining the product leaving the skeleton isomerization section with the remaining part of the mixture comprising n-butane and isobutane and sending the mixture thus obtained to a dehydrogenation section of paraffins; c) sending the stream leaving the dehydrogenation to a selective hydrogenation of butadiene; d) sending the stream leaving the selective hydrogenation section to a first conversion section in which the isobutene is reacted by dimerization separating the dimerized product from the non-reacted C 4 hydrocarbon stream, which comprises isobutane, n-butane and linear butenes, and subjecting said product to hydrogenation, thus providing a hydrocarbon stream comprising iso-octane; e) sending the C 4 hydrocarbon stream leaving the first conversion section, to a second conversion section in which all the linear butenes are reacted by alkylation with isobutane obtaining a stream of saturated hydrocarbons; f) sending the non-reacted butanes in the second conversion section to a first separation column (deisobutanizing column) from whose head a stream comprising propane and isobutane is recovered and from whose bottom n-butane is recovered to be recycled to the skeleton isomerization section; g) sending the stream at the head of the first separation column (deisobutanizing column) to a second separation column (depropanizing column) from whose head the light products are recovered and from whose bottom the isobutane is recovered, which is recycled to the second conversion section and/or to the first conversion section and/or to the selective hydrogenation section.