Effects of the solvent ratio on carbon nanotube blended polymeric membranes

Membrane operations are used in a vast range of industries. Hence, there is neither a single type of membrane nor a single technology (Cardew and Le, 1998). Membrane operations use a membrane to execute a particular separation. Due to physical and/or chemical differences between the membrane and the permeating components, membrane can transport some elements more readily than others (Mulder, 1997). Membrane operations can be classified according to the driving force, the mechanism of separation, the structure of the membrane and the phases in contact (Aptel and Buckley, 1996). Most of the membrane operations are governed by the pressure, concentration, electrical potential or temperature gradients (Cardew and Le, 1998). In pressure driven membrane operations the driving force is the pressure difference across the membrane. Main pressure driven membrane operations are reverse osmosis, nanofiltration, ultra-filtration, and microfiltration. Typical properties of the pressure driven operations are given in Table 6.1.