Ruthenium-based catalyst for producing lower polyhydric alcohols

A method of producing a catalyst comprising from 0.5 to 5% by weight of ruthenium supported on granulated activated carbon useful for hydrogenolysis under pressure of higher polyhydric alcohols, wherein it comprises the steps of:

• (a) suspending granular activated carbon in water, the granular activated carbon having:
• a specific surface area of from 600 to 1000 m2/g;
• a total pore volume of from 0.5 to 1.2 cm3/g;
• an apparent specific weight (bulk density) of from 0.45 to 0.55 g/cm3;
• an actual specific weight of from 1.9 to 2.3 g/cm3;
• a total volume of micropores having a radius smaller than 75 A of from 0.4 to 0.55 cm3/g;
• and
• an ash content of from 2 to 5% by weight;
• (b) adding an aqueous ruthenium chloride solution to the suspension;
• (c) adjusting the pH of the suspension to a value of between 4.5 and 8 by adding an alkaline agent;
• (d) heating the suspension to a temperature of between 70° and 100° C. and maintaining the suspension at this temperature for a time of between 30 minutes and 2 hours;
• (e) separating the solid from the suspension by filtration;
• (f) re-suspending the solid in a solution of alkaline agent by heating the suspension to a temperature of between 60° and 100° C.;
• (g) reducing the catalyst obtained by bubbling a hydrogen flow into the suspension for a time of between 1 and 3 hours;
• and
• (h) separating the solid from the suspension.

A method of producing a catalyst comprising from 1 to 3% by weight of ruthenium supported on granulated activated carbon, useful for hydrogenolysis under pressure of higher polyhydric alcohols, wherein it comprises the steps of:

• (a) suspending granular activated carbon in water, the granular activated carbon having:
• a specific surface area of from 600 to 1000 m2/g;
• a total pore volume of from 0.5 to 1.2 cm3/g;
• an apparent specific weight (bulk density) of from 0.45 to 0.55 g/cm3;
• an actual specific weight of from 1.9 to 2.3 g/cm3;
• a total volume of micropores having a radius smaller than 75 A of from 0.4 to 0.55 cm3/g;
• and
• an ash content of from 2 to 5% by weight;
• (b) adding an aqueous ruthenium chloride solution to the suspension;
• (c) adjusting the pH of the suspension to a value of between 4.5 and 8 by adding an alkaline agent;
• (d) heating the suspension to a temperature of between 70° and 100° C. and maintaining the suspension at this temperature for a time of between 30 minutes and 2 hours;
• (e) separating the solid from the suspension by filtration;
• (f) re-suspending the solid in a solution of alkaline agent by heating the suspension to a temperature of between 60° and 100° C.;
• (g) reducing the catalyst obtained by bubbling a hydrogen flow into the suspension for a time of between 1 and 3 hours;
• and
• (h) separating the solid from the suspension.

A catalyst comprising ruthenium in an amount from 0.5 to 5% by weight supported on active granulated carbon of vegetable origin, the catalyst being capable of catalyzing hydrogenolysis of higher polyhydric alcohols under pressure, the catalyst having:

• (a) a specific surface area of from 600 to 1000 m2/g;
• (b) a total pore volume of from 0.5 to 1.2 cm3/g;
• (c) a total volume of micropores having a radius smaller than 75 Å of from 0.4 to 0.55 cm3/g;
• and
• (d) an ash content of from 2 to 5% by weight.