COADSORPTION OF HYDROCARBONS AND WATER ON BPL ACTIVATED CARBON

A novel experimental apparatus is used to measure hexane, acetone, water, hexane/water, and acetone/water isotherms on BPL activated carbon. Isotherms for pure components are measured from 25 to 125-degrees-C with hydrocarbon pressures varied by a factor of 10(7), from low values to saturation. Emphasis is placed on measuring the hysteresis loop in the water and hydrocarbon/water systems. For adsorption of pure water, the location and size of the hysteresis loop is found to be temperature dependent, with the loop shifting toward higher relative pressures and narrowing as temperature is increased. For the hydrocarbon/water mixtures, the hydrocarbon loading is held constant and water isotherms are measured at 25 and 100-degrees-C. The partial pressure of the hydrocarbon is found to increase dramatically at constant hydrocarbon loading as the water loading is increased. Also, hysteresis is observed in the hydrocarbon partial pressure depending on whether the system is on the adsorption or desorption branch of the water isotherms. Behavior is complex and is interpreted qualitatively.