Nien-Hwa Wang is the Maxine Spencer Nichols Professor in the Davidson School of Chemical Engineering. Her research interests are in chemical and biochemical separations. Current projects are focused on adsorption and chromatography processes, which are highly selective and versatile techniques capable of producing pure materials of uniform size, shape, composition, and surface properties. The goals of her research are to understand the kinetics and equilibrium of competitive adsorption at liquid-solid interfaces and to develop novel, economical large scale adsorption processes. Various theoretical analyses, computer simulations, and experimental studies are used to address these key issues. In collaboration with industry and national laboratories, her research group is developing novel large scale simulated moving bed (SMB) chromatography processes for the recovery of nonbiodegradable chemicals from waste streams and a variety of biochemicals including sugars, antibiotics, anticancer drugs, amino acids, peptides, and proteins from biological sources. Analysis based on the concept of standing concentration waves has been developed to facilitate the design and optimization of multiple system and operating parameters in SMB systems for multicomponent fractionation. Computer simulations based on a detailed parallel pore and surface diffusion model have been developed to understand the transient wave propagation and its relation to port movement frequency and intra-column and extra-column mass transfer effects. A systematic SMB design and optimization method based on the standing wave analysis has been established. A versatile simulated moving bed pilot plant has been developed and tested for multi-component separation.
