Study of the Chemical Interaction of Gases with Activated Carbon.

摘要

This project was initiated to apply the newly developed technique of Fourier Transform infrared Photoacoustics to the study of activated carbon in the presence of various sorbate gases. The FTIR-PAS measurement is sensitive to reflectivity due to large extinction coefficients. It is also quite sensitive, especially in the spectral overtones region, to particle size when the particle size is less than 50 microns n diameter. FITR-PAS is capable of less than 0.1% precision of measurement and has been shown to be quantitative at least for internally calibrated samples of reproducible mesh. FTIR-PAS spectra do not match normal absorbance spectra. Residual absorption from scattering from the particles in solid state samples shows itself as a broad underlying background signal. There is no commercially available standard carbon black. For the study of adsorption of sample gases much shallower sampling depths than available for this work must be used. The standard hexane-soot prepared for these studies was found to undergo chemical relaxation under normal atmospheric conditions over a period of 48 hours, after which it was observed to be chemically stable.