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Application of ultrasound for degradation of benzophenone-3 in aqueous solutions
Zúñiga-Benítez, H.; Soltan, J. & Peñuela, G. A.
Abstract
This paper reports the results of an experimental
work on sonochemical degradation of benzophenone-
3 (BP3), one of the most commonly used ultraviolet
(UV) filters whose disruptive effect on the endocrine system
of various living beings has been demonstrated.
Ultrasound irradiation is a promising advanced oxidation
technology that has received considerable interest as an
alternative for degradation of persistent organic pollutants
through hydroxyl free radicals that are generated from the
cavitation bubbles implosion. Taking into account the
potential risk due to the presence of BP3 in the environment
and its possible removal using ultrasound, the effect
of operating parameters such us ultrasonic applied power,
pollutant initial concentration, pH, the presence of gases
(including ozone), inorganic anions and alcohols on the
substrate removal was investigated. During sonochemical
treatment, a higher pollutant degradation rate was achieved
by increasing the power in a range of 40.2–80.1 W. Likewise,
at lower benzophenone-3 initial concentrations,
higher extents of degradation were observed, which could
be explained by a heterogeneous kinetics model. Acidic pH
enhanced the pollutant initial degradation by 21 %. Oxygen,
ozone and bicarbonate ions affected positively the
benzophenone-3 removal, while nitrogen, nitrate and
chloride anions inhibited it. Measurements of concentration
of hydroxyl free radicals indicated that by promoting OH∙
radical formation, the pollutant elimination rate can be
increased.
Keywords
Advanced oxidation process; Benzophenone-3; Hydroxyl radicals; Sonochemical degradation; Water treatment
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