Method of removing residual active oxy-hydrogens
View Patent ↗A method of efficiently removing active oxy-hydrogens (e.g., existing as hetero element-containing functional groups such as COOH, CHO, and OH) present in a carbon material at a relative low temperature. The invention also provides a carbon-activating material adapted for use in a polarizable electrode typically used in an electrical double-layer capacitor. The method of removing residual active oxy-hydrogens in the carbon material starts with mixing the carbon material and a transition metal or a transition metal compound. The resulting mixture is thermally processed within a stream of a reducing gas. Preferably, the transition metal or transition metal compound is removed from the thermally processed mixture.
1. A method of removing residual active oxy-hydrogens from carbon material, comprising the steps of:
mixing said carbon material and at least one of a transition metal and a transition metal compound to thereby produce a mixture;
thermally processing the obtained mixture within a stream of a reducing gas, thereby removing active oxy-hydrogens present in said carbon material; and
removing the transition metal and/or transition metal compound from said thermally processed mixture.
2. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said carbon material is one of activated carbon, porous carbon, and nonporous carbon, and wherein said carbon material from which the residual activated carbon oxides have been removed is used as a carbon-activating material for use in a polarizable electrode.
3. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said reducing gas is either hydrogen or the mixture gas 3H 2 +N 2 obtained by catalytically decomposing ammonia.
4. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said one of a transition metal and a transition metal compound is a transition metal mixed with a fine powder of said carbon material, and wherein said transition metal mixed with said fine powder of said carbon material assumes any one of finely powdered form, mesh product made of thin wire, dendritic product, and floccular product.
5. A method of removing residual active oxy-hydrogens as set forth in claim 4 , wherein said transition metal is selected from the group consisting of Fe, Ni, Co, Cu, Mo, Cr, Mn, and Th, compounds of at least two of these metals, and alloys including one of Fe, Ni, Co, Cu, Mo, Cr, Mn, and Th.
6. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said one of a transition metal and a transition metal compound is a transition metal, and wherein said carbon material and said transition metal compound are mixed by carrying said transition metal compound on said carbon material.
7. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said one of a transition metal and a transition metal compound is a transition metal compound, and wherein said transition metal compound is one of an inorganic compound and an organic salt capable of being thermally decomposed into a metal.
8. A method of removing residual active oxy-hydrogens as set forth in claim 1 ,wherein:
(A) said one of a transition metal and a transition metal compound is a transition metal;
(B) said transition metal is selected from the group consisting of Fe, Ni, and Co, compounds of at least two of these metals, and alloys including one of Fe, Ni, and Co; and
(C) said transition metal is removed from said thermally processed mixture by a magnetic force.
9. A method of removing residual active oxy-hydrogens as set forth in claim 1 wherein said one of said transition metal and transition metal compound is removed from said thermally processed mixture according to a difference in density with said carbon material.
10. A method of removing residual active oxy-hydrogens as set forth in claim 1 , wherein said step of thermally processing the obtained mixture is carried out at a temperature of between 200° C. and 850° C.
11. A method of producing a refined carbon material, comprising the steps of:
mixing a carbon material and one of a transition metal and a transition metal compound to thereby produce a mixture;
thermally processing the obtained mixture within a stream of a reducing gas; and
removing one of the transition metal and transition metal compound from the thermally processed mixture, thereby obtaining a refined carbon material from which active oxy-hydrogens have been removed.