Production of high viscosity index lubricants
US5358628A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 1992 |
| Grant date | Oct 25, 1994 |
| Priority date | — |
| Expiry date | Jun 15, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G2400/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Petroleum wax feeds are converted to high Viscosity Index lubricants by a two-step hydrocracking-hydroisomerization process in which the wax feed is initially subjected to hydrocracking under mild conditions with a conversion to non-lube range products of no more than about 30 weight percent of the feed. The hydrocracking is carried out at a hydrogen pressure of at least 1000 psig using an amorphous catalyst which preferentially removes the aromatic components present in the initial feed. The hydrocracked effluent is then subjected to hydroisomerization in a second step using a low acidity dicarboxylic acid-treated zeolite Beta or mordenite catalyst which effects a preferential isomerization on the paraffin components to less waxy, high V.I. isoparaffins. The second stage may be operated at high pressure by cascading the first stage product into the second stage or at a lower pressure, typically from 200 to 1000 psig. The second stage catalyst is preferably a noble metal containing zeolite Beta catalyst which is treated with oxalic acid to give a low Alpha Value, typically below 10. The second stage is carried out at relatively low temperature, typically from 600.degree. to 650.deg…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.