Treatments of Pharmaceuticals and Personal Care Products
Among various photocatalysts, photocatalytic removal of pharmaceuticals and personal care products in water using titanium dioxide (TiO 2 ) powder or nanoparticles,
especially Degussa P25 – a commercially available TiO 2 – has been extensively
investigated. Effects of photocatalyst amount, light source, and pH of the solution
have also been studied to determine the optimum conditions for pharmaceuticals and
personal care products removal over powder suspension in water. The examples are
photocatalytic removal of crotamiton, clofibric acid, and sulfamethoxazole using
TiO 2 under UV irradiation. Crotamiton is an antipruritic frequently detected in
Japanese rivers. The removal efficiency of crotamiton is not affected by the initial
pH of the solution in the range of 3–9, whereas the removal efficiencies of clofibric
acid and sulfamethoxazole are significantly decreased when the initial pH is adjusted
higher than 6.5, because of repulsive force between TiO 2 particle and these pollutants (Fukahori et al. 2012). Photocatalytic removal of ibuprofen, which is the
common nonsteroidal anti-inflammatory drugs (NSAID) in the presence of TiO 2
powder suspended in the wastewater under UV/visible light irradiation is another
example. Ibuprofen can be rapidly mineralized over TiO 2 . However, small amounts
of intermediates in the form of oligomeric species can be detected during the
photocatalytic reaction, leading to catalyst deactivation (Choina et al. 2013). The
utilization of solar light, replacing an expensive and bio-hazardous UV light, as a
light source is receiving considerable attention for photocatalytic removals of pharmaceuticals and personal care products, such as photocatalytic removals of amoxicillin over tungsten trioxide (WO 3 ) (Nguyen et al. 2019) and photocatalytic
removals of caffeine over titanium dioxide (TiO 2 ) and zinc oxide (ZnO)
nanoparticles (Ghosh et al. 2019).
Treatments of Persistent Organic Pollutants
In the case of elimination of persistent organic pollutants in water, photocatalysis
using powder photocatalysts can be successfully applied for various target pollutants, such as diuron, alachlor, isoproturon, atrazine (Cruz et al. 2017), chlorpyrifos,
cypermethrin, chlorothalonil (Affam and Chaudhuri 2013), rhodamine B, aldicarb,
norfloxacin (Li et al. 2013), and perfluorooctanoic acid (Zhao et al. 2012).
Photocatalytic mineralization of the representatives of aqueous persistent organic
pollutants was performed, e.g., rhodamine B, aldicarb, and norfloxacin as representatives of color substances, pesticides, and antibiotics, respectively (Li et al. 2013).
Under simulated sunlight irradiation, rhodamine B and norfloxacin can be
decomposed, while aldicarb is difficult to be decomposed (Li et al. 2013).
Perfluorooctanoic acid is a recent-found hazardous persistent organic pollutant.
The shorter chain compounds of perfluorooctanoic acid are less bioaccumulative
and produce a low level of environmental pollution; therefore photocatalytic degradation of perfluorooctanoic acid is increasingly interested as one of the alternative
treatment processes. Photocatalytic degradation of perfluorooctanoic acid using
26
P. Kemacheevakul and S. Chuangchote
Among various photocatalysts, photocatalytic removal of pharmaceuticals and personal care products in water using titanium dioxide (TiO 2 ) powder or nanoparticles,
especially Degussa P25 – a commercially available TiO 2 – has been extensively
investigated. Effects of photocatalyst amount, light source, and pH of the solution
have also been studied to determine the optimum conditions for pharmaceuticals and
personal care products removal over powder suspension in water. The examples are
photocatalytic removal of crotamiton, clofibric acid, and sulfamethoxazole using
TiO 2 under UV irradiation. Crotamiton is an antipruritic frequently detected in
Japanese rivers. The removal efficiency of crotamiton is not affected by the initial
pH of the solution in the range of 3–9, whereas the removal efficiencies of clofibric
acid and sulfamethoxazole are significantly decreased when the initial pH is adjusted
higher than 6.5, because of repulsive force between TiO 2 particle and these pollutants (Fukahori et al. 2012). Photocatalytic removal of ibuprofen, which is the
common nonsteroidal anti-inflammatory drugs (NSAID) in the presence of TiO 2
powder suspended in the wastewater under UV/visible light irradiation is another
example. Ibuprofen can be rapidly mineralized over TiO 2 . However, small amounts
of intermediates in the form of oligomeric species can be detected during the
photocatalytic reaction, leading to catalyst deactivation (Choina et al. 2013). The
utilization of solar light, replacing an expensive and bio-hazardous UV light, as a
light source is receiving considerable attention for photocatalytic removals of pharmaceuticals and personal care products, such as photocatalytic removals of amoxicillin over tungsten trioxide (WO 3 ) (Nguyen et al. 2019) and photocatalytic
removals of caffeine over titanium dioxide (TiO 2 ) and zinc oxide (ZnO)
nanoparticles (Ghosh et al. 2019).
Treatments of Persistent Organic Pollutants
In the case of elimination of persistent organic pollutants in water, photocatalysis
using powder photocatalysts can be successfully applied for various target pollutants, such as diuron, alachlor, isoproturon, atrazine (Cruz et al. 2017), chlorpyrifos,
cypermethrin, chlorothalonil (Affam and Chaudhuri 2013), rhodamine B, aldicarb,
norfloxacin (Li et al. 2013), and perfluorooctanoic acid (Zhao et al. 2012).
Photocatalytic mineralization of the representatives of aqueous persistent organic
pollutants was performed, e.g., rhodamine B, aldicarb, and norfloxacin as representatives of color substances, pesticides, and antibiotics, respectively (Li et al. 2013).
Under simulated sunlight irradiation, rhodamine B and norfloxacin can be
decomposed, while aldicarb is difficult to be decomposed (Li et al. 2013).
Perfluorooctanoic acid is a recent-found hazardous persistent organic pollutant.
The shorter chain compounds of perfluorooctanoic acid are less bioaccumulative
and produce a low level of environmental pollution; therefore photocatalytic degradation of perfluorooctanoic acid is increasingly interested as one of the alternative
treatment processes. Photocatalytic degradation of perfluorooctanoic acid using
26
P. Kemacheevakul and S. Chuangchote