Tuesday, May 3, 2011
Separations in a biorefinery will require use of membranes to improve energy efficiency and because many of the components are non-volatile. Optimization of membrane performance requires continuous monitoring of permeate flux and composition to assess selectivity. One of the obstacles to developing and commercializing biorefinery membrane systems is a lack of instrumentation to assess membrane performance in real time. Raman spectroscopy offers the potential to make rapid and accurate measurements of both carbohydrate and lignin contents in biorefinery streams. The purpose of our research is to assess potential for membranes to separate sugars from lignin in a biorefinery process stream and apply Raman Spectroscopy for rapid and accurate measurements of both sugar and lignin contents in membrane permeate stream. The results of the preliminary study show that 5000 Dalton membrane provides good separation of sugars from lignin in synthetic solution. The lignin concentration determined by Raman spectroscopy correlates well with determination using UV spectroscopy (R2=.995). This work demonstrates application of Raman spectroscopy to enhance membrane separation research and its potential for commercial application.