Abstract
An automated gravimetric measuring system has been developed to study adsorption and desorption of gases on fine powders. With interchangeable Dewar and furnace systems, the temperature range of weight change measurements is −196° to 500°C. The high-vacuum system has the capability of operating below the 10−7-torr range at a temperature to permit thorough outgassing of materials being studied. The automated features of the system include an adjustable programmed pressure controller which permits unattended recording of weight change as a function of pressure. This feature permits automatic recording of adsorption isotherms such as are required for surface area determinations. Initially the equipment was used to study the adsorption of CO2 on ferric oxide. A type I adsorption curve was obtained at all three temperature conditions measured, with some evidence of chemisorption.