Functionalized and Responsive Membranes for Water- Related Applications: An Overview

摘要

Membrane processes provide a highly flexible separation technique for water treatment and materials recovery. The special features for membrane processes that make them attractive are their compactness, ease of fabrication, operation, and modular design. The development of responsive, multifunctional materials and membranes for water applications requires a high level of control of both the characteristics of the base polymeric support layer, as well as, its corresponding pore configurations. Microfiltration membranes are primarily used for the removal of bacteria and particles, but on the other hand by appropriate pore functionalization (with polymeric charge groups or integration of nanoparticles) of these MF membranes (termed Functionalized Membranes) one can use these as high capacity metal capture membranes to catalysis and pH/temperature flux modulations with separation selectivity. Depending on the types of functionalized groups (such as, chain length, charge of groups, biomolecule, etc.) and number of layers, these materials and membranes could be used in applications ranging from tunable metal (or oxyanions) separation to oxidative reactions. The dependence of conformation properties of polyelectrolytes provides tunable separation and membrane flux control by pH-based stimuli responsive properties. Layer-by-layer (LBL) assembly technique, most commonly conducted by intercalation of positive and negative polyelectrolytes or polypeptides, is a powerful, versatile and simple method for assembling supramolecular structures.