Patent GB-630246-A (GB)
Title: Improvements relating to the production of motor fuels of high octane number
IPC: C10L1/06
Filed: 1941-02-24
Abstract: Hydrocarbon distillates of gasoline boiling range are fractionated according to the process described in Specification 600,551 to separate fractions containing normal hydrocarbons, i.e. n-pentane, n-hexane, and n-heptane from the isopentane, isohexane and isoheptane fractions and the normal hydrocarbon fractions are thermally reformed at high temperature and the reformed products blended with the isofractions to give a motor fuel of high octane value.  The normal hydrocarbon fractions are preferably subjected prior to the reforming treatment to solvent extraction with sulphur dioxide and the raffinate obtained is then subject to the thermal reforming treatment while the extract is distilled to separate solvent, and recover aromatic fractions which are added to the blended fuel.  Straight-run distillate is passed into the middle section of the first of a series of fractionating towers a, b, c, d, e, the bottom fraction from each tower being passed to the middle portion of the succeeding tower. Fractionating <PICT:0630246/III/1> conditions as to temperature, pressure and reflux ratio are controlled as decribed in Specification 600,551 to remove overhead from towers a, c, e, respectively the isopentane, isohexane and isoheptane fractions which are blended in line h3 while the normal pentane and hexane fractions are removed overhead from towers b, d and the normal hexane and higher boiling fraction from the bottom of tower e, these fractions being blended and passed to the thermal reforming plant.ALSO:<PICT:0630246/IV (b)/1> Hydrocarbon distillates of gasoline boiling range are fractionated according to the process described in Specification 600,551 to separate fractions containing normal hydrocarbons, i.e. n-pentane, n-hexane, and n-heptane from the iso-pentane, iso-hexane and iso-heptane fractions, and the normal hydrocarbon fractions are thermally reformed at high temperature and the reformed products blended with the iso-fractions to give a motor fuel of high octane value.  The normal hydrocarbon fractions are preferably subjected prior to the reforming treatment to solvent extraction with sulphur dioxide and the raffinate obtained is then subjected to the thermal reforming treatment while the extract is distilled to separate solvent, and recover aromatic fractions which are added to the blended fuel.  Straight run distillate is passed into the middle section of the first of a series of fractionating towers a, b, c, d, e, the bottom fraction from each tower being passed to the middle portion of the succeeding tower.  Fractionating conditions as to temperature, pressure and reflux ratio are controlled as described in Specification 600,551, [Group III], to remove overhead from towers a, c, e, respectively the iso-pentane, iso-hexane and iso-heptane fractions which are blended in line h3 while the normal pentane and hexane fractions are removed overhead from towers b, d and the normal hexane and higher boiling fraction from the bottom of tower e, these fractions being blended and passed to the thermal reforming plant.