Process for preparing vicinal glycol esters from olefins

Claim 2

The process of claim 1 wherein said residue is contacted with said carboxylic acid medium by recycling said residue to said oxidation zone.

Claim 3

In the process for the preparation of vicinal glycol esters by the reaction of an olefin, moleculAr oxygen and a carboxylic acid, said reaction being carried out in the liquid phase within an oxidation zone in the presence of catalyst consisting essentially of (a) a variable valence metal cation selected from the group consisting of tellurium, cerium, antimony, vanadium, gallium, arsenic, copper, selenium and silver and (b) at least one of bromine, chlorine, a bromine-containing compound capable upon oxidation of yielding bromide ions in solution, or a chlorine-containing compound capable upon oxidation of yielding chloride ions in solution, the improvement which comprises: continuously removing a liquid effluent from said oxidation zone; separating said effluent to obtain a residue having a boiling point higher than that of said vicinal glycol ester; separating from said effluent unreacted carboxylic acid contained in said effluent; recovering glycol ester product from said effluent; separating from said effluent a stream comprising precursor light components contained in said effluent; contacting said residue with a liquid medium comprising a caroboxylic acid whereby additional glycol ester is obtained.

Claim 4

The process of claim 4 wherein said carboxylic acid medium contains the same carboxylic acid as used in the oxidation zone.

Claim 5

The process of claim 4 wherein in addition to said residue, the precursor light components are also contacted with said carboxylic acid medium.

Claim 6

The process of claim 4 wherein said carboxylic acid medium is maintained at from about 90*C. to about 180*C.

Claim 7

The process of claim 4 wherein the carboxylic acid is a lower carboxylic acid of from two to six carbon atoms.

Claim 8

The process of claim 8 wherein the olefin is a lower olefin of from two to five carbon atoms.

Claim 9

The process of claim 8 wherein said olefin is ethylene.

Claim 10

The process of claim 8 wherein said olefin is propylene.

Claim 11

A process in accordance with claim 6 wherein both said residue and said precursor light components are recycled to said oxidation zone to effect said contact.

Claim 12

A process in accordance with claim 4 wherein the catalyst is tellurium cation and at least one of bromine and a bromine-containing compound capable upon oxidation of yielding bromine ions in solution.