Chemistry Reference
In-Depth Information
outside a normal batch reactor, which acts as a
reservoir within which conventional chemistry can
occur. Such an arrangement allows the ultrasonic
dose of energy entering the reaction to be controlled
by the transducer power input and flow rate (resi-
dence time). Temperature control is achieved
through heat exchange in the circulating reaction
mixture.
Pipes of various cross-sectional geometry can be
converted to flow processors by generating ultra-
sonic vibrations through their walls. The length of
pipe must be designed accurately so that a null point
exists at each end and then it can be retro-fitted to
existing pipework. Such systems are capable of han-
dling high flow rates and viscous materials. There are
four common cross-sectional geometries: rectangu-
lar, pentagonal, hexagonal and circular. The pentag-
onal pipe provides a fairly uniform ultrasonic field
because the energy from each irradiating face is
reflected at an angle from the two opposite faces.
The other configurations provide a 'focus' of energy
in the centre, where direct energy and that reflected
from the opposite wall meet.
3.
Abramov, O. V.
High-intensity Ultrasound: Theory and
Industrial Applications
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4.
Mason, T. J.
Ultrasonics
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5.
Suslick, K. S.
Ultrasound: its Chemical, Physical and Bio-
logical Effects.
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6.
Mason, T. J.
Sonochemistry: the Uses of Ultrasound in
Chemistry.
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7.
Mason, T. J.
Sonochemistry
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Povey, M., & Mason, T. J.
Ultrasound in Food Process-
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Crum, L. A., Mason, T. J., Reisse, J. L., & Suslick,
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7 Conclusions
Through the cavitational energy provided by power
ultrasound, sonochemistry is finding a niche as a
clean technology for the future. Trends that are now
evident include chemical synthesis, sonocatalysis,
environmental remediation and the use of ultra-
sound to enhance electrochemistry, biotechnology
and photochemistry. The future prospects are likely
to encompass a much wider range of applications as
the frequency effects are exploited and more studies
of sonochemical reaction mechanisms are embarked
upon. Equipment design is coming on apace both
in the laboratory and in development work for the
scale-up of sonochemistry and processing.
Sonochemistry is an expanding field of study that
continues to thrive on outstanding laboratory results
that have even more significance now that scale-up
systems are available.
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Luche, J.-L., & Cintas, P. In
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