Condensed phase catalytic hydrogenation of lactic acid to propylene glycol
US6403844B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1999 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Nov 19, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J21/18
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention provides a process for production of propylene glycol with high yield and selectivity in an aqueous reaction mixture of lactic acid and hydrogen with an essentially pure elemental ruthenium catalyst on an inert support at elevated pressure and temperature. In particular, the present invention provides a process wherein the catalyst is a ruthenium salt deposited on a microporous support, reduced to ruthenium on the support with hydrogen, and oxidized in the presence of oxygen to provide a ruthenium oxide surface on the surface of the ruthenium metal and wherein the catalyst is maintained in the surface oxidized state until it is reduced with hydrogen prior to the reaction process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.