INVESTIGADORES
MARTIN Carlos Alberto
congresos y reuniones científicas
Título:
Kinetics and Modelling of Dichloroacetic Acid Oxidation Using Ozone and UV Radiation
Autor/es:
LOVATO, MARIA EUGENIA; MARTIN, CARLOS ALBERTO; CASSANO, ALBERTO ENRIQUE
Lugar:
Praga
Reunión:
Congreso; 6th European meeting on Solar Chemistry and Photocatalysis: Environmental Applications (SPEA6); 2010
Resumen:
Dichloroacetic Acid (DCA) is a water pollutant very often found as a DPB
of natural water chlorination resulting from the combination of free
chlorine with humic substances regularly present. Ozone is an oxidizing
agent showing a high reactivity with a large number of organic
compounds. The reaction of ozone with organic substrates follows two
reaction mechanisms: (i) direct reaction of molecular ozone and (ii)
indirect reactions involving radicals formed in the ozone
decomposition in water. The direct oxidation by ozone molecule is
selective to unsaturated electron-rich bonds contained in specific
functional groups, but relatively slow. On the other hand, indirect
oxidation reaction by means of radicals proceeds at a faster rate but
with low selectivity, which makes this reaction interesting for
degrading many types of organic compounds. This process occurs slowly in
water, and the decomposition process can be accelerated with UV
radiation, since the photolysis of ozone produces hydrogen peroxide as
primary product, which can then photolyze into a hydroxyl radical
directly, or can react with molecular ozone to produce the hydroxyl
radical. In this work, degradation of DCA by direct photolysis, O3 alone
and the O3/UV process were studied and evaluated to successfully model
the reacting system. The effects of different operating variables were
investigated and oxidation by-products were identified and quantified,
in order to develop an operative reaction scheme.