The influence of treatment with ammonia on. adsorption properties toward CO2 was examined for commercially available CWZ-35 activated carbon. The treatment was performed for 2 h at elevated temperatures ranging from 200 to 1000 degreesC. The surface groups were determined by Fourier transform infrared (FTIR) spectroscopy of solid. Additionally FTIR measurement was done for outlet gases evolved during temperature-programmed desorption from the ammonia-treated activated carbon. FTIR spectra of solid samples confirmed the presence of N-containing groups in ammonia-treated carbon. Adsorption properties against CO2 were checked for both pristine and ammonia-treated activated carbons using thermogravimetric analysis. Activated carbon treated with ammonia demonstrated distinct enhancement in adsorption of CO2. (C) 2003 Elsevier B.V. All rights reserved.