Catalyst for reducing lower polyhydric alcohols by hydrogenolysisal higher polyhydric alcohols and method for preparing catalyst

A method for preparing a catalyst composition for hydrogenolysis reactions of higher polyhydric alcohols, comprising the steps of:

• I) preparing an aqueous solution consisting of a compound of ruthenium and tin;
• II) putting this aqueous solution into contact with an aqueous suspension of activated carbon, and regulating the pH by adding an alkaline agent until a value of between 4.5 and 8 is obtained, the activated carbon having:
• a) a specific surface area of 600 to 1000 m.sup.3 /g;
• b) a total pore volume of 0.5 to 1.2 cm.sup.2 /g;
• c) an apparent specific weight (bulk density) of 0.45 to 0.55 g/cm.sup.3 ;
• d) an actual specific weight of 1.9 to 2.3 g/cm.sup.3 ;
• e) a total volume of micropores having a radius smaller than 75 .ANG. of 0.4 to 0.55 cm.sup.3 /g;
• and
• f) an ash content of 2 to 5 weight %;
• III) heating to a temperature of 60.degree. to 100.degree. C. for a time sufficient to give rise to depositing of the metals on the activated carbon, and separating this solid;
• IV) suspending the solid thus obtained in an alkaline solution and hydrogenating the suspension thus obtained with gaseous hydrogen at a temperature of between 60.degree. and 100.degree. C. for a time sufficient to give rise to reduction of the metals deposited on the support, the concentration of the metals in the solution I) being such as to obtain a catalyst composition comprising:
• a) 0.5 to 5 weight % ruthenium;
• b) 0.1 to 10 weight % tin.