Kaneko, T. Suzuki, Y. Fujiwara and K. Nishikawa

Department of Chemistry, Faculty of Science, Chiba University 1-33 Yayoi, Chiba 260, Japan 

Cellulose(CEL)- and polyacrylonitrile(PAN)-based ACF s and coconut-shell granular activated carbons (AC) were used in this study. Also nonporous carbon black(NPC) whose surface area Is 81 m g was examined by in situ XRD for comparison. The adsorption Isotherms of water at 298 K and N2 at 77 K on samples were measured gravimetrically. The ACF sample was pre-evacuated at 383 K and 1 mPa for 15 h prior to the adsorption. The evolved gas analyses (EGA) of ACF samples preheated at 373 K under 1 mPa for 15 h were carried out at a heating rate of 10 K min with the aid of a mass filter(ULVAC, MSQ-150A). The elemental analysis for the nitrogen atom of the ACF samples was done the ratios of nitrogen to carbon in wt. % of CEL and PAN were 2 and 6-7, respectively. 

The in situ XRD patterns of ground ACF samples were measured with an automatic powder diffratometer (Rlgaku 2028) of the diffraction cell with Kapton wlndows[10]. The radiation was Nickel filtered CuKoC operated at 35 kV and 10 mA. The accuracy in the reflection angle was examined by use of a Grafoil. The ground ACF sample after drying at 383 K for 2h was wetted in water, then it was compacted to a pellet, which was mounted in the diffraction cell. 

The changes in XRD patterns of the wet ACF pellet with evacuation by a rotary pump were measured at 298 K. The SAXS spectra of ACF previously dried at 403 K were measured under varying relative humidities (RH) at 298 K. The Cu Koc X-ray beam operated at 30 kV and 30 mA was used after monochroraati2ation[14]. 

Also the adsorption isotherm of N2 on AC was of Type I. These samples have considerably uniform micropores. The surface area a., external surface area ext t micropore volume 

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