Production of catalytically active activated carbons
The invention is directed to a method for preparing catalytically active activated carbon, to catalytically active activate carbon obtainable by the method, and to the use of the catalytically active activated carbon. The method of the invention method comprises the steps of: i) mixing charcoal with one or more organic nitrogen-containing compounds, said nitrogen-containing compounds comprising, next to a first nitrogen atom, at least two or more further heteroatoms selected from the group consisting of nitrogen and oxygen, wherein said further heteroatoms have a lone pair; ii) drying the mixture obtained in step i); iii) activating the dried mixture using steam, thereby producing catalytically active activated carbon.
1. Method for preparing catalytically active activated carbon comprising micropores, mesopores and macropores, said method comprising the steps of:
i) mixing charcoal with one or more organic nitrogen-containing compounds, said nitrogen-containing compounds comprising one or more moieties selected from the group consisting of amines, amides, nitriles, nitrosamines, cyanates, isocyanates, and oximes;
ii) drying the mixture obtained in step i);
iii) activating the dried mixture using steam, thereby producing catalytically active activated carbon,
wherein the mixture obtained in step i) is not carbonised before being activated using steam in step iii).
2. Method according to claim 1 , wherein the one or more nitrogen-containing compounds comprise two or more groups selected from the group consisting of —NH 2 , ═O, —OH, ═NH and —NH—.
3. Method according to claim 1 , wherein the one or more nitrogen-containing compounds are selected from the group consisting of urea, N-butylurea, biuret, 2-cyanoguanidine, guanidine, biguanide, cyanuric acid, creatinine, ammeline, ammelide, hexamethylenetetramine, melamine, ammonium lignosulphonate, and derivatives thereof.
4. Method according to claim 1 , wherein said charcoal is wood char.
5. Method according to claim 1 , wherein said charcoal is in the form of charcoal chunks, charcoal chips, and/or charcoal powder.
6. Method according to claim 1 , wherein the dried mixture entering the steam activation in step iii) is catalytically inactive.
7. Method according to claim 1 , wherein in step ii) the mixture is dried to a moisture content of 10 wt. % or less based on total weight.
8. Method according to claim 1 , wherein the steam activation of step iii) results in a burn-off of 10-80 wt. %.
9. Method according to claim 1 , wherein the amount of the one or more nitrogen-containing compounds in the mixture is such that the amount of nitrogen atoms is 0.1-8 wt. % based on the total weight of the charcoal.
10. Method according to claim 1 , wherein said catalytically active activated carbon is in particulate form having particles with an average particle size of 1-200 μm as determined by laser diffraction, or in granulate form having granules with an average particle size of 0.2-5 mm.
11. Method according to claim 10 , wherein said catalytically active activate carbon has a hydrogen peroxide conversion time using the hydrogen peroxide conversion test as described herein of 40 minutes or less.
12. Method according to claim 10 , wherein said catalytically active activate carbon has an iodine number in the range of 400-2000 mg/g as determined by ASTM D4607-94.