Abstract: Novel process for the preparation of an arylglyoxylic acid compound, e.g., phenylglyoxylic acid, which comprises oxidizing an .alpha.-hydroxyarylacetic acid, e.g., mandelic acid, of the formula ##STR1## in which m is 1, 2 or 3,each R individually is hydrogen, alkyl, cycloalkyl,aryl, aralkyl, alkoxy, cycloakoxy, aryloxy, hydroxyl,halogen, aminoalkyl or carboxyl,with the proviso thattwo R's together can represent the methylenedioxygroup or a fused-on, optionally heterocyclic andoptionally substituted ring,with oxygen or a gas containing molecular oxygen in aqueous alkaline medium in the presence of a catalyst comprising a platinum-group metal in the presence as an activator of at least one of lead, a lead compound, bismuth and a bismuth compound at a temperature of up to the boiling point of the resulting reaction mixture.

Abstract: A process for the preparation of pure 2-hydroxybenzyl alcohol, pure 4-hydroxybenzyl alcohol or a mixture of both hydroxybenzyl alcohols by reacting phenol and formaldehyde in the presence of a basic catalyst and subjecting the resulting reaction mixture to an at least 2-stage countercurrent extraction in a solvent system of water/organic solvent which is water-immiscible or water-miscible only to a limited extent.

Abstract: A process for the tertiary dealkylation of a tertiary alkyl containing m- and/or p-cresol wherein a tertiary alkyl containing m- and/or p-cresol is continously introduced into a reaction vessel with a small amount of sulfuric acid or an quivalent amount of a sulfonic acid and the reaction vessel contains a high concentration of m- and/or p-cresol or a high boiling phenol which under the prevailing reaction conditions is not substantially vaporized from the reaction mixture. The reaction mixture is maintained at a temperature of no greater than 230.degree. C. The reaction products are withdrawn continuously from the reactor (and separated into its components) and at the same time a small amount of the reaction mixture being withdrawn intermittently or continously from the reactor.

Abstract: A process for the continuous preparation of a ditertiary butylcresol wherein m- or p-cresol is reacted with isobutene at elevated temperature using H.sub.2 SO.sub.4 as catalyst wherein the process is carried out stepwise by introducing stepwise into a reaction mixture comprising substantially all of the cresol to be reacted with isobutene. The total amount of isobutene introduced is introduced such that less isobutene is charged in a last stage of the process than in the first stage thereof. Thereafter the catalyst is deactivated.

Abstract: Salicylaldehyde and other hydroxybenzaldehydes are prepared by oxydation of a hydroxybenzyl alcohol in the presence of a platinum metal catalyst and lead, silver, tellurium or tin or compounds thereof as activator.

Abstract: A process for the removal of acids and potential acid-forming agents from a composition containing such acids and potential acid-forming agents and an alkylphenol which composition is obtained by reacting phenols with alkenes in the presence of sulfuric acid or a sulfonic acid, and for treating the effluent thereby obtained, the process being characterized by the steps of:(a) extracting a major amount of the acid constituents from the alkylphenol mixture by means of water;(b) treating the alkylphenol mixture with a dilute aqueous alkali solution in an amount such that the alkali is insufficient to neutralize all the acid originally present in the alkylphenol mixture,(c) separating the alkylphenol mixture from the aqueous alkali solution;(d) combining the aqueous phases obtained from steps (a) and (b);(e) heating the combined aqueous phases to a temperature of 100.degree. to 200.degree. C,(f) separating off the organic phase obtained in step (e); and(g) discharging the aqueous phase.