Abstract: The invention concerns a method for producing esters of a hydroxy acid and a C1-C8 alcohol. The invention is characterized by the fact that the esterification is carried out by reactive distillation on a heterogeneous catalyst. The invention makes it possible in particular to produce high purity lactic acid esters in high yields.

Abstract: In a process for selective crystallization of 2,6-dialkyl-naphthalene selected from the group consisting of methyl-n-propyl-naphthalene, methyl isopropyl-naphthalene, ethyl-isopropyl-napthalene, ethyl-n-butyl-naphthalene, di-n-propyl-naphthalene, diisopropyl-naphthalene, methyl-amyl-naphthalene, ethyl-amyl-naphthalene, propyl-amyl-naphthalene, di-n-butyl-naphthalene and diisobutyl-naphthalene from their isomer mixtures from a polar solvent solution, the improvement comprising effecting the crystallization with constant stirring at a temperature from 25.degree. to -30.degree. C. to obtain the 2,6-dialkyl-naphthalene at least 95% pure.

Abstract: A process for the preparation of 2,6-dialkyl-naphthalenes comprising selectively alkylating naphthalene or 2-alkyl-naphthalene with alkylating agent in the presence of a zeolite catalyst at 250.degree. to 345.degree. C. which dialkyl-naphthalenes are useful for the preparation of naphthalene 2,6-dicarboxylic acid used to produce high-quality polyesters or polyamides.