Enhanced adsorption of phenol from water by ammonia-treated activated carbon.

Influence of treatment with gaseous ammonia on adsorption properties toward phenol from water was examined for commercially available CWZ-series activated carbons. The treatment was carried out at elevated temperatures ranged from 400 degrees C to 800 degrees C for 2 h. In comparison with untreated material, activated carbons modified with ammonia demonstrated enhanced adsorption of phenol from water. The enhancement depended on the treatment temperature and porous structure of studied activated carbons. Fourier transform infrared spectroscopy (FTIR) measurements confirmed presence of N-containing species in ammonia-treated activated carbons. Optimal conditions of the modification with ammonia were determined. Influence of the N-containing groups and porous structure of activated carbons on adsorption of phenol is discussed.