Environmental Engineering Reference
In-Depth Information
state of knowledge toward both the science and technology of these bio-inspired sys-
tems [72,111-114]. In particular, mimicking ion-channel-gating behavior for the transport
and control of ions has generated signiicant interest leading to the development of luidic
transistors [73] and conical nanopores for ion pumps for the potassium ion [115] (Figure
27.16). One advantage of bio-inspired systems is that the fundamental processes occur at
the nanoscale and engineering these systems could allow for rapid development of bio-
nanotechnology as a core area for water desalination research. Furthermore, with most
biological systems operating near thermodynamic energy minima, such systems hold the
promise of delivering the most energy-eficient water desalination systems ever conceived.
However, signiicant questions remain open and would likely need extensive investiga-
tions. Molecular dynamic simulations begin to answer some of these questions and sug-
gest that for electrokinetic low of an electrolytic nanoilm where non-uniform charge
exists (i.e., charged patches were introduced), low of water and ions can be controlled by
manipulating a combination of axial electric ield and charge density of the patches. This
simulation shows promise for ion control at the nanoscale [116] with potential to develop
systems as these recent simulations use length scales currently accessible by fabrication
technologies.
27.4 Summary and Conclusions
In this chapter, the current state of knowledge of water desalination methods was pre-
sented with a comparison between commonly used methods and opportunities for further
research and growth. Throughout the chapter, the focus was on the energy-water nexus,
i.e., the consumption of energy to generate freshwater from salt water. Consequently,
many innovative and emerging technologies were discussed, highlighting the exciting
opportunities for future development in desalination and water puriication but also the
need for further understanding either in basic science or engineering systems to engineer
and implement these technologies in an energy-eficient manner. While biotechnology
and nanotechnology provide interesting clues on developing novel systems for ion trans-
port with applications in water desalination, many scientiic and technological questions
remain open.
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