Abstract: A continuous catalytic hydrogenation process, in which a reaction mixture containing the substance to be hydrogenated, the hydrogenation product, hydrogen and the hydrogenation catalyst suspended in the reaction mixture is recirculated in a reactor. Part of the hydrogenation product is removed from the reactor and the substance to be hydrogenated and hydrogen are fed into the reaction. In this process the substance to be hydrogenated and the hydrogen are mixed before entering the reactor. A venturi nozzle is particularly suitable as the mixing device.

Abstract: A continuous catalytic hydrogenation process, in which a reaction mixture containing the substance to be hydrogenated, the hydrogenation product, hydrogen and the hydrogenation catalyst suspended in the reaction mixture is recirculated in a reactor. Part of the hydrogenation product is removed from the reactor and the substance to be hydrogenated and hydrogen are fed into the reaction. In this process the substance to be hydrogenated and the hydrogen are mixed before entering the reactor. A venturi nozzle is particularly suitable as the mixing device.

Abstract: A continuous catalytic hydrogenation process, in which a reaction mixture containing the substance to be hydrogenated, the hydrogenation product, hydrogen and the hydrogenation catalyst suspended in the reaction mixture is recirculated in a reactor. Part of the hydrogenation product is removed from the reactor and the substance to be hydrogenated and hydrogen are fed into the reaction. In this process the substance to be hydrogenated and the hydrogen are mixed before entering the reactor. A venturi nozzle is particularly suitable as the mixing device.

Abstract: A continuous catalytic hydrogenation process, in which a reaction mixture containing the substance to be hydrogenated, the hydrogenation product, hydrogen and the hydrogenation catalyst suspended in the reaction mixture is recirculated in a reactor. Part of the hydrogenation product is removed from the reactor and the substance to be hydrogenated and hydrogen are fed into the reaction. In this process the substance to be hydrogenated and the hydrogen are mixed before entering the reactor. A venturi nozzle is particularly suitable as the mixing device.

Abstract: Tartaric acid is produced by epoxidizing acid calcium maleate with aqueous hydrogen peroxide in the presence of a tungstic acid-containing catalyst to produce sparingly soluble acid calcium cis-epoxysuccinic acid, which is suspended in a solvent medium comprising an organic solvent or a mixture of organic solvent and water and treated with sulphuric acid. Calcium sulphate is formed and separated and the liberated organic acids consisting essentially of epoxysuccinic acid are then hydrolyzed in an aqueous medium to form tartaric acid. The organic solvent may be one in which epoxysuccinic acid is soluble and may be immiscible or miscible with water. If the solvent is imiscible with water the epoxysuccinic acid may be transferred to the aqueous medium in which it is hydrolyzed by liquid-liquid extraction.