Process for making double metal cyanide catalysts
US5783513A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1997 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | Mar 13, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J27/26
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for making substantially non-crystalline double metal cyanide (DMC) catalysts having improved activity and performance is disclosed. The process comprises using a metal salt having an alkalinity within the range of about 0.2 to about 2.0 wt. % as metal oxide based on the amount of metal salt to prepare the catalyst. Surprisingly, important polyol properties such as viscosity and unsaturation improve when the alkalinity of the metal salt used to make the DMC catalyst is properly controlled. The process allows catalyst producers to enjoy the benefits of substantially non-crystalline DMC catalysts even when relatively inexpensive, technical-grade metal salts are used to make the catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.