Study of time-dependent diffusion coefficient membrane systems and its application to extractions from sugarcane bagasse

Abstract

It is widely recognized that the mathematical modeling of mass transfer in membrane processes is an essential component not only for understanding the underlying mechanisms associated with the transport, but also that is a powerful tool for design, cost estimation, control and scale-up of extraction processes. Here, a simple methodological approach for the study and description of diffusional changes during the extraction and transport processes in liquid membrane systems is developed and evaluated in the extraction and transport of gallic acid from aqueous solutions. It is concluded that, in comparison with the use of flux and distribution coefficient in function on time, a more sensitive description of diffusion coefficient can be performed using mass-transport coefficient in function on the time. In addition, it is concluded that, during the polyphenol extraction by liquid membrane based on castor oil and Cyanex 921, transportation can be affected by dissolution of membrane phase in the feed phase, and evidenced by a negative value of g in function of time. Diffusion coefficientLiquid membrane Mass-transport coefficient Coupled transport M.