Abstract: In a process for the preparation of methylglyoxal dimethyl acetal from methylglyoxal and methanol in the presence of an acidic ion exchanger, water is introduced in an amount sufficient to form an acidic reaction mixture in which the acetal product and water form an azeotropic mixture, with or without the retention of some methanol reactant. After subjecting a single phase acidic reaction mixture to an azeotropic distillation, it will separate into two distinct liquid phases with a simple recovery of the acetal product from the aqueous phase.

Abstract: Supported catalysts containing silver and alkali metals, for the preparation of ethylene oxide from ethylene and oxygen in the gas phase, are prepared or regenerated by modifying, respectively, a new or spent supported catalyst which already contains metallic silver and may or may not contain the light alkali metals lithium and/or sodium and, where a spent catalyst is concerned, also contains the heavy alkali metals potassium, rubidium and/or cesium, with a solution containing the heavy alkali metals, the modifier solution used containing(a) a surfactant and/or a reducing agent, in the case of the preparation of a new catalyst or(b) a surfactant, in the case of the regeneration of a spent catalyst.

Abstract: A catalyst for the manufacture of ethylene oxide, giving improved yield and having a long life, based on an alkali metal-modified silver catalyst on an oxide carrier is obtained by providing the silver-containing catalyst, in the reduced state, with the alkali metal by applying an alcoholic alkali metal salt solution which also contains an organic oxygen compound or nitrogen compound which forms complexes with silver ions.

Abstract: A novel catalyst for the manufacture of ethylene oxide from ethylene by means of oxygen or air, comprising from 2 to 12% of silver on a conventional carrier, together with from 0.1 to 2 atom% (based on silver) of lithium and from 0.05 to 0.35 atom% of potassium or 0.003 to 0.25 atom% of rubidium or 0.0005 to 0.2 atom% of cesium or mixtures of potassium, rubidium and/or cesium in amounts exhibiting corresponding catalytic activity. The catalyst is advantageously obtained by heating a carrier which is impregnated with a silver complex compound.