Process for producing activated carbon

Claim 1

A process for producing activated carbon which comprises: a. charging an internal space of an internally heated rotary furnace, said furnace having a charge inlet at one end thereof, an opposed discharge outlet at the other end thereof and a ratio of length to diameter of from 1:1 to 10:1, with a mixture of an organic material capable of being carbonized at a temperature of 200°C or higher, and a material containing therein at least one metal compound capable of reacting with carbonized organic material at a temperature of at least 500°C to form activated carbon, said metal compound being selected from the group consisting of metal oxides, carbonates and hydroxides, through the inlet of said rotary furnace; b. rotating said rotary furnace to cause said mixture of said organic material and said metal compound-containing material to travel from the feed end to the opposite discharge end of said rotary furnace through a distillation and carbonization zone and an activation zone in said internal space of said rotary furnace; c. blowing air or oxygen gas into said internal space of said rotary furnace from and through said opposite discharge end thereof in a direction which is parallel to the longitudinal axis of said rotary furnace or inclined at an angle from said axis towards an inside periphery surface of said rotary furnace; d. heating said mixture in said distillation and carbonization zone at a temperature of at least 200°C to carbonize said organic material in said mixture and to generate from said organic material combustible distilled gas; e. heating the resulting mixture containing said carbonized material in contact with said metal compound in said activation zone at a temperature of at least 500°C to activate said carbonized material, to reduce said metal compound and to generate carbon monoxide which, together with said distilled gas serves as the sole fuel used to generate heat in said process; f. contacting said distilled gas and carbon monoxide with said blown air or oxygen at a temperature of at least 500°C to burn said distilled gas and carbon monoxide; g. whereby the burnt gas including said air or oxygen gas is uniformly circulated throughout said internal space of said rotary kiln by said blowing of said air or oxygen gas to provide the heat required by said heating steps (d) and (e).