Transient rates of gas sorption. I. Measurement of rapid gas uptake by Oxide Catalysts

Abstract

The rate of gas uptake by a porous solid in a constant volume system was deter- mined by measuring the decrease in pressure, using a capacitance-type glass diaphragm manometer. Techniques are described for admitting gas to adsorbent quickly, and for measuring rapid changes at low pressures and high temperatures. For water and alcohols the rates of uptake by thoria and alumina at 110-200 °C were found to have a negative temperature coefficient. Rates were first order with respect to initial pressure. Three types of rate dependence on mass of adsorbent were found - first, zero, and second order or exponential.