Preparation of carboxylic acid esters with BF.sub.3 complex catalyst
USRE31010E · kind E · reissue
Assignee
Inventor
Key dates
| Filing date | Jun 11, 1981 |
| Grant date | Aug 10, 1982 |
| Priority date | — |
| Expiry date | Jun 11, 2001 |
Classification
- Technology area (CPC —)General
Abstract
In a process wherein ethylene or propylene is carbonylated with carbon monoxide to form carboxylic acid esters in the presence of a catalyst complex of one mole of BF.sub.3 and one mole of alcohol, the invention concerns a technique wherein the catalyst is recovered from the reaction product and recycled. The carbonylation is carried out until approximately one-half of the alcohol is consumed, to form a reaction mass containing the BF.sub.3, the alcohol, and the carboxylic acid ester in a 2:1:1 molar ratio. In the first step, the one mole of the free BF.sub.3 is vaporized from the reaction mass. The remaining admixture is a 1:1:1 mixture of the three aforesaid compounds. To this mixture additional alcohol is added and the mixture is subjected to distillation. A carboxylic acid ester/alcohol azeotrope and residual alcohol are removed by the distillation, to leave a residue containing a 1:2 BF.sub.3 /alcohol complex. This complex is combined with an additional mole of BF.sub.3 to form the 1:1 catalyst complex used in the carbonylation. The additional mole of BF.sub.3 is preferably that initially separated from the reaction mass; however, it may be obtained from an external source. Th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.