4 - Organic-inorganic nanocomposite membranes for molecular separation processes

Abstract

Publisher Summary The discovery of novel materials with unique properties can profoundly impact existing technologies as well as enable development of entirely new products and processes. Such breakthrough potential has led to considerable research into organic–inorganic composites. Through hybridization, one hopes to capture the desirable attributes of the organic and inorganic components in a single material and possibly to discover new synergistic properties. In most cases, the best property enhancements are achieved when the inorganic and/or organic components are of sufficiently small dimensions to blend at a molecular level. Such nanocomposites frequently take the form of nanoscale inorganic particles dispersed in an organic matrix. Nanocomposites may also prove to be useful for molecular separations, a diverse field affecting processes such as biomolecule purification, environmental remediation, seawater desalination, and petroleum chemicals and fuel production. Separations in these applications are often accomplished using energy-intensive, established technologies, such as distillation, absorption, and adsorption. Membrane separation can be an attractive alternative because membranes are a low-cost, energy-efficient, green technology. Their widespread use in separation applications has been limited, however, by the difficulty of preparing membranes with the desirable combination of high selectivity, which yields high product purity and low operating costs, and high permeability, which reduces membrane area and capital cost. This chapter reviews the history and current state-of-the-art for molecular separations using organic/inorganic nanocomposite membranes.