Effects of catalytic mineral matter on CO/CO[sub 2] ratio, temperature and burning time for char combustion

We have extended our recently reported method for determining the surface area of single microporous particles, Dudek et al., 1989 using an electrodynamic chamber (EDC) by increasing the operating pressures from 1 at to 25 at. The value of total surface area is determined from adsorption measurements of CO[sub 2] assuming monolayer adsorption. Measurements of CO[sub 2] desorption were also carried out to yield a point to point difference from the adsorption measurements of about 1%. Adsorption-desorption cycles were carried out for 10 particles to yield a scatter of less than 5% in the measured value for saturation adsorption. The major advantage of using high pressure measurements for evaluating the saturation value for CO[sub 2] adsorption is the improved accuracy of the extrapolation procedure. Previous measurements with the EDC at atmospheric pressure, Dudek, et al., 1989, yielded values for the surface area for similar particles of comparable value with a relative error of about 15%. The results of the high pressure measurements are however bounded with an error of about 3%. Also, the equilibrium adsorption-desorption coefficient was found with a high accuracy, whereas from atmospheric measurements it was not practical to obtain an accurate value