| 摘要 |
PROBLEM TO BE SOLVED: To suppress the release of a chemical substance from activated carbon and the generation of dust, to remarkably improve the ability of the carbon to adsorb chemical substances, especially volatile org. compds. and to remarkably increase the amt. of chemical substances adsorbed by impregnating an aq. sodium silicate soln. into the activated carbon and coating the pores in the carbon with a thin glassy film. SOLUTION: Activated carbon is added to an aq. sodium silicate soln. enough for impregnation and they are mixed under mild stirring so that the powdering of the carbon is not caused. In order to accelerate the penetration of the sodium silicate soln. into the pores in the carbon, a vessel contg. the resultant mixture is evacuated and the internal pressure is suddenly raised preferably to atmospheric pressure by introducing gas into the vessel. The sodium silicate soln. is forced to enter the pores in the activated carbon and satisfactory impregnation is carried out in a relatively short time. The activated carbon is then taken out, freed of the soln. and dried preferably under heating. The surface of the activated carbon and the surfaces of the pores in the carbon are coated with a thin glassy sodium silicate film. |
