Functionalized Membranes for Sorption, Separation, and Reaction: An Overview

Functionalized membrane processes are finding wide applications ranging from water treatment to reactors to advanced bioseparations. In this chapter, applications of functionalized membranes in the area of sorption, separation, and reaction are discussed with specific examples. Selected examples for sorption applications include ethoxylated nonionic surfactants sorption from hydrophobic solvent and metal sorption from aqueous solutions. Membranes functionalized with either single layer or layer-by-layer assembly of charged polyelectrolytes have been discussed for separation applications of various ionic and neutral solutes. Charge-based ion exclusion with highly open geometries and high permeabilities is a distinct advantage of the ionizable polyelectrolyte functionalized membranes. Applications of functionalized membranes in the area of reaction by providing alternative support for catalyst immobilization are discussed with reference to catalytic dechlorination of chloro-organics. It was demonstrated that in situ formation of membrane immobilized structured bimetallic nanoparticles offers an efficient way for complete dechlorination of toxic chloro-organics at room temperature.