[Studies on the adsorption removal of ammonia gas. 1) Adsorption of ammonia gas on several kinds of activated carbons (author's transl)].

The present study was designed to secure some fundamental informations on the adsorption removal of ammonia gas by the static method. In order to find out the suitable activated carbons for the adsorption removal of ammonia gas, amounts of ammonia gas adsorbed on twelve kinds of activated carbons were measured at 30 degrees C and up to 70,000 ppm of ammonia gas. The relations between the amounts of ammonia gas adsorbed on the activated carbons and the physical properties of them were discussed through the results of specific surface area, pore volume, mean pore radius, scanning electron micrograph, pH, and amount of base. The results were as follows: 1) Among the twelve kinds of activated carbons, the activated carbons No. 2, No. 3, and No. 6 adsorbed larger amount of ammonia gas than the others. 2) Adsorption of ammonia gas on the activated carbons seemed to be mainly physical as judged from the values of heat of adsorption. 3) The adsorption capacity of the used activated carbons can be recovered to the original capacity by some treatment. 4) The period to reach adsorption equilibrium was about 5 minutes. 5) It may be concluded that adsorption of ammonia gas on the activated carbons was decided mainly by the surface properties (pH and amount of base) of the activated carbons rather than their porous structures.