Isomerization process with preliminary normal paraffin and mono-methyl paraffin feed capture step
US4982048A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 24, 1989 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | Feb 24, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G53/08
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a process for increasing the octane of a refinery gasoline pool by segregating components of a feed stream to increase the value of select components by isomerization and to prevent isomerization of other components already having a high octane value. The preferred feed stream of this process comprises di-branched paraffins, mono-methyl-branched paraffins and normal paraffins. Two or more different separatory sieves are used prior to isomerization. A first separatory shape-selective molecular sieve has a pore size of 4.5.times.4.5A or smaller to adsorb normal paraffins. A second separatory shape-selective molecular sieve has a pore size of 5.5.times.5.5 to 4.5.times.4.5A but excluding 4.5.times.4.5A. These sieves may be situated in a series flow arrangement. Normal paraffins are adsorbed by the first sieve. Mono-methyl-branched paraffins are adsorbed by the second sieve. The paraffins captured by both sieves are desorbed to form an isomerization zone feed stream which is isomerized to produce additional di-methyl branched paraffins. The isomerization zone effluent stream can undergo further separation to provide a recycle stream comprising normal paraffins…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.