Synthesis, characterization, and performance of nitrated polysulfone membranes

Wholly aromatic polysulfone was modified by nitration and was investigated as a possible membrane material for separation of inorganic solutes, low mo lecular weight organic solutes and dyes from aqueous solutions. The nitrate d polysulfones were characterized in terms of extent of nitration, percent moisture regain, inherent iscosity, IR spectra, TGA/DTA and DSC data. Membr anes were prepared from nitrate polymer and performance characteristics in terms of permeate flux and solute separation are reported. The effects of t he casting solution composition and casting condition, effect of feed conce ntration and separation of different inorganic salts are also included. Sep aration data for low molecular weight polyethylene glycol (PEG) solutes and dyes are studied. Nitrated polysulfone membranes have been found to give h igher separation for polyvalent anionic electrolytes. The stability of memb ranes in acid and alkaline medium and chlorine tolerance of the membranes a re also investigated.