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Ammonia adsorption on bamboo charcoal with acid treatment

Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 956– 8603, Niigata, Niigata, Japan; Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 956–8603, Niigata, Niigata, Japan
Journal of Health Science 01/2006; 52:585-589. DOI: 10.1248/jhs.52.585

ABSTRACT The effect of ammonia adsorption in aqueous solutions was examined for bamboo charcoal carbonized at 400, 700 and 1000°C, and activated carbon. Furthermore, the change of the ammonia adsorption in aqueous solutions was also examined by treatment of each sample with diluted sulfuric acid. Bamboo charcoal carbonized at 400°C and treated with diluted sulfuric acid was the most effective for removing ammonia from aqueous solutions. Al-though the ammonia adsorption of the bamboo charcoal carbonized at 400°C in gas phase hardly changed by the treatment with diluted sulfuric acid, that in aqueous solutions significantly increased by the treatment. duced and removing ammonia all year around is needed. Many reports have describes the adsorption of ammonia gas by activated carbon and charcoal. 7–19) The charcoal carbonized from 400 to 500°C is found effective for the adsorption of basic ammonia gas due to many acidic functional groups on its sur-face. 7–11) It is also described that the adsorption amount of the ammonia gas on activated carbon in-creases by modifying the acidic functional groups on the surface of the activated carbon with an oxi-dizing reagent. 20,21) In aqueous solutions, properties differing from the gas phase are expected because ammonia with a high solubility in water is easily soluble and NH 4 + is formed on the basis of the solu-tion of pH. However, the properties of the ammonia adsorption in aqueous solutions have not been re-ported except for ammonia adsorption in the gas phase on activated carbon and charcoal. In this study, the relation between the carbonization temperature and ammonia adsorption was examined in order to effectively remove ammonia from aqueous solutions. Furthermore, the improvement of the adsorption capacity of ammonia by treatment with dilute acid was examined.

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