Cyclic process for hydrotreating petroleum feedstocks
US5707511A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1994 |
| Grant date | Jan 13, 1998 |
| Priority date | — |
| Expiry date | Dec 22, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G45/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process for simultaneously removing heteroatoms, such as sulfur, from a virgin distillate stream and a light catalytic cyclic stream in two reaction zones in a hydrotreating process unit. One reaction zone will be a low temperature reaction zone and the other will be the high temperature zone. In the low temperature reaction zone, the cracked stream is reacted with a hydrotreating catalyst at a predetermined temperature and in high temperature reaction zone, the virgin distillate stream is reacted with a catalyst which is less reactive than that of the first reaction zone. When catalyst in the high reaction zone is replaced with fresh catalyst the temperature is lowered so that it now becomes the low temperature zone in which the cracked stream is redirected. Correspondingly, the virgin stream is redirected to the other reaction zone whose temperature is now raised and which becomes the high temperature zone and which now contains a catalyst less active than the low temperature reaction zone which now contains the fresher more active catalyst. This cyclic operation is repeated each time fresh catalyst is substituted for spent catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.