Abstract: Catalysts and catalyst carriers, in the form of granules having a definite geometric form, characterized by porosity values such that at least 70% of the volume of the pores have a radius corresponding to the peak values of the porosity distribution curve. The catalysts and catalyst carriers are obtained by compression shaping, wherein the lubricant employed is applied to the molding of the chamber (external lubrication).

Abstract: A ruthenium-based hydrogenation catalyst, particularly but not exclusively for hydrogenolysis under pressure of higher polyhydric alcohols, comprises ruthenium supported on granular activated carbon, and has:a specific surface area of from 600 to 1000 m.sup.2 /g;a total pore volume of from 0.5 to 1.2 cm.sup.3 /g;an apparent specific weight (bulk density) of from 0.45 to 0.55 g/cm.sup.3 ;an actual specific weight of from 1.9 to 2.3 g/cm.sup.3 ;a total volume of micropores having a radius smaller than 75 A of from 0.4 to 0.55 cm.sup.3 /g; andan ash content of from 2 to 5% by weight.The catalyst is used in a method for the continuous production of lower polyhydric alcohols in a fixed bed reactor, by means of hydrogenolysis under pressure of higher polyhydric alcohols.

Abstract: A metallic catalyst composition on an inert support, suitable in particular for hydrogenolysis reactions of higher polyhydric alcohols, characterized in that it comprises the following relative to 100 parts of the catalyst:a) 0.5 to 5 weight % ruthenium;b) 1 to 10 weight % of a metal selected from the group consisting of palladium, platinum and rhodium; andc) 0.5 to 2.5 weight % copper,in which the copper content is lower than the content of the metal b).The catalyst is used in particular for producing lower polyhydric alcohols such as ethanediol, propylene glycol, butanediol and glycerol, by means of hydrogenolysis reaction of higher polyhydric alcohols.

Abstract: A metallic catalyst composition on an inert support, suitable in particular for hydrogenolysis reactions of higher polyhydric alcohols, characterised in that it comprises the following relative to 100 parts of the catalyst:a) 0.5 to 5 weight % ruthenium;b) 1 to 10 weight % of a metal selected from the group consisting of palladium, platinum and rhodium; andc) 0.5 to 2.5 weight % copper,in which the copper content is lower than the content of the metal b).The catalyst is used in particular for producing lower polyhydric alcohols such as ethanediol, propylene glycol, butanediol and glycerol, by means of hydrogenolysis reaction of higher polyhydric alcohols.