Page 624 - Polymer-based Nanocomposites for Energy and Environmental Applications

576 Polymer-based Nanocomposites for Energy and Environmental Applications

Nonequilibrium based
pressure-driven MF, UF, NF, RO, PV, GP
membrane processes
Membrane technology membrane processes Forward osmosis,
Nonequilibrium based
nonpressure driven
Dialysis, ED

Equilibrium based
nonpressure driven
liquid membranes
membrane processes

Equilibrium based Membrane
pressure driven distillation
membrane processes
Fig. 21.7 Schematic representation of membrane processes.
Reproduced with the permission from Copyright 2016 Elsevier.

Conventional nanocomposite Thin-film nanocomposite

Surface located nanocomposite
TFC with nanocomposite substrate
Fig. 21.8 Typical types of nanocomposite membranes.
Reproduced with the permission from Copyright 2015 Elsevier.

their large specific surface area and high reactivity. The high surface-area-to-mass
ratio of nanomaterials can greatly improve the adsorption capacities of sorbent mate-
rials. Magnetic nanoadsorbents are particularly attractive as they can be easily
retained and separated from treated water. However, the small particle size of NPs
brings excessive pressure drops when NPs are applied in fixed bed or any other
flow-through systems and certain difficulties in separation and reuse. Hybrid
nanocomposites are fabricated by impregnating the fine particles onto solid particles
of larger size to overcome the limitations of NPs. The resultant polymer-based
nanocomposite (PNC) retains the inherent properties of NPs, while the polymer sup-
port materials provide higher stability, processability, and improvements caused by
the NPs-matrix interaction [27].