Thermally-induced hydrolysis of acetal

A process for the selective, thermally-induced hydrolysis of acetals to the corresponding aldehydes and alcohols is disclosed, involving heating and pressurizing a substantially acid-free acetal containing solution to effect the rapid hydrolysis of the acetals without significant harm to the remaining reaction system components, and removing the treated solution from the reaction zone as product.

I claim:

1. A process for the selective-thermally induced hydrolysis of acetals to the corresponding lower non aromatic aldehydes and alcohols of about 2 to 6 carbon atoms, comprising:

forming a substantially catalyst-free, acetal-containing solution;

heating and pressurizing the acetal-containing solution to a temperature above about 140.degree. C. and a corresponding pressure ranging from about 50-5000 psia to effect the substantial hydrolysis of the acetal present in the solution to the corresponding non aromatic aldehyde and alcohol of about 2 to 6 carbon atoms; the reaction occurring in a suitable amount of water;

removing the resultant liquid solution as product.

2. A process as claimed in claim 1 wherein the acetal containing solution is formed by separating the solution from any acidic catalyst component present.

3. A process as claimed in claim 2 wherein the acidic catalyst component is separated from the acetal-containing solution by distillation.

4. A process as claimed in claim 1 wherein the acetal-containing solution is the effluent from the reductive carbonylation of methanol.

5. A process as claimed in claim 1 wherein the acetal-containing solution is heated to about 150.degree.-250.degree. C.

6. A process as claimed in claim 1 wherein the pressure is about 100-2000 psia.

7. A process as claimed in claim 1 wherein the amount of water present in the hydrolysis reaction system ranges from about 200/1 to 0.1/1 moles H.sub.2 O per mole of acetal.

8. A process as claimed in claim 7 wherein the amount of water present is about 10 moles H.sub.2 O per mole of acetal.

9. A process as claimed in claim 1 wherein the process is a batch process.

10. A process as claimed in claim 1 wherein the process is a continuous process.

11. A process as claimed in claim 1 wherein dimethoxy ethane is substantially hydrolyzed to acetaldehyde and methanol.