Polysulfone Based Membranes for Removal of Polysaccharides from Aqueous Solutions by Means of Ultrafiltration Process

Abstract

This study concerns the ultrafiltration of aqueous solutions of water-soluble polysaccharides. The process is used to remove carboxymethylcellulose and soluble starch from aqueous solutions. These biopolymers are widely used in the textile industry as sizing agents and their recovery is of great importance relating to evident economic and environmental benefits, since both the size agents and the clean water are reusable inside mill processes and since the rejected liquid wastes must be as clean as possible.
Polysulfone and poly(sodium 4-styrene sulfonate) were blended so as to obtain materials of various compositions and the blends were used to prepare ultra?ltration membranes by phase-inversion method. Then, the polysulfone based membranes, employed in a magnetic stirred cell, operating in a batch mode, were used to remove the polysaccharides from aqueous solutions. To investigate the performance of the membranes in removing the macromolecular species, the Dubois spectroscopic method was used.
The objective of this paper is to present and describe the Dubois colorimetric method and to discuss the use of this method in the analysis of the permeates resulting from ultrafiltration of polysaccharides aqueous solutions. It will focus on the accuracy of the method and its suitability for this application.