Process for batchwise acetal production

A process for batchwise production of an acetal of the general formula ##STR5## wherein X and X' are the same or different and each represent a hydrogen or halogen atom, an alkyl or alkoxy group containing 1 to 4 carbon atoms or a carboxyl group, m and n each represent an integer of 1 to 5 and p is 0 (zero) or 1, which comprises subjecting (a) a polyhydric alcohol of the general formula ##STR6## wherein p is as defined above, and (b) a benzaldehyde compound of the general formula ##STR7## wherein X and n are as defined above, or a benzaldehyde compound of the general formula ##STR8## wherein X' and m are as defined above, or a mixture of said compound of general formula (III) and said compound of general formula (IV), to condensation reaction in a reactor by feeding a homogeneous solution or suspension containing

• (a) said polyhydric alcohol of general formula (II),
• (b) said compound of general formula (III) or (IV) or said mixture,
• (c) a lower alcohol and, optionally,
• (d) an acid catalyst,
• to the reactor, together with a hydrophobic organic solvent, continuously or intermittently while adjusting the rate of feeding of said homogeneous solution or suspension such that said polyhydric alcohol of general formula (II) and said compound of general formula (III) or (IV) or said mixture are fed to the reaction system in a total amount per hour of about 0.1 to about 2 parts by weight per part by weight of the acetal of general formula (I) as found in the reaction system.