MULTICOMPONENT MASS TRANSPORT IN AQUEOUS AND MEMBRANE SYSTEMS

The term "multicomponent mass transport, " as used here re fers to those physical processes whereby molecular species in a mixture are caused to move relative to one another. By such processes a change in composition can be brought about. For example, consider a sample of water containing a pollu tant, say a dissolved pesticide. Suppose that a portion of this aqueous solution is forced through a suitable porous membrane by the use of pressure. In general, the membrane is more easily penetrated by the small water molecules than by the larger molecules of pesticide. Thus, the effluent from the low pressure side of the membrane will contain a very much reduced pesticide concentration. Therefore, it is possible to extract potable water from a contaminated source through use of a pressure difference and a suit able membrane. The rate and efficiency of this and similar pro cesses is determined by the rates of mass transfer across a multicomponent system consisting of water, pesticide, and the membrane matrix. It is to the quantitative prediction of the rates and efficiencies of such multicomponent mass transfer operations that this work is addressed. Processes involving such multicomponent mass transport are found throughout the water resource field. For example, the kinetics and efficiency of membrane desalination processes are governed by rates of mass transport. Similar membrane processes have been proposed for use in contaminate removal from a wide variety of industria