Environmental Engineering Reference
In-Depth Information
Fenton reactions have been widely utilized to degrade organic compounds. However, due to some drawbacks (Section 24.5)
of this process, a new technology in treating organic compounds is needed. in order to overcome this drawback, more recently,
a novel sono-Fenton system was developed that could offer advantages including working at neutral pH, no sludge generation,
and the possibility of recycling the iron reagent [84b].
Some new studies on the use of ultrasonic irradiation in photocatalysis, electro-oxidation, and Fenton processes are summa-
rized in Table 24.4 [84b, 114, 116, 117].
24.7
coNclusioN
Since the definition of the concept of a catalyst given by Berzelius in 1836, the field of catalysis has experienced an aston-
ishing transformation. The success of basic research in the field of catalysis has had a direct effect on solving many
fundamental technological and environmental problems. regardless of the intended application, the common challenge of
achieving long-lasting, highly active, selective, and environmental-friendly catalytic materials and processes still remains.
Nanocatalysis is one of the most exciting subfields to have emerged from nanoscience. Nanomaterials also provide unprec-
edented opportunities to develop more efficient water-purification catalysts and redox-active media. This chapter has given
further evidence to this issue and has tried to address what all the potential environmental impacts of the nanocatalyst might
be. despite recent positive progress, additional investigations of the risks of nanomaterials to the environment as well as
their toxicity and persistence are still needed, as this type of understanding is a requirement for the rational design of
efficient catalysts.
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