Overview of polymer–TiO2 catalyst for aqueous degradation of pharmaceuticals in heterogeneous photocatalytic process

There is a great deal of concern about the presence of pharmaceutical pollutants (PP) in water from various sources. The applications of heterogeneous photocatalysis using titanium dioxide (TiO2) for water treatment have been a feasible technology to overcome the occurrence of PP in water and wastewater. At the same time, polymer composite has proven as an excellent material due to its wide range of applications. Polymer modification of TiO2 enhances its effectiveness for visible light absorption employing sensitization. Hence, research interest, in the field of photocatalysis, has recently shifted to TiO2-based polymer nanocomposites, due to their exceptional optical, electrical, adsorptive, and catalytic properties. This article provides a review of various polymer-modified TiO2, as excellent adsorbent and photocatalytic materials for heterogeneous photocatalytic degradation of pharmaceutical and other organic pollutants. Discussions were also made on the basic principles of the heterogeneous photocatalytic process as it applies to the use of TiO2 and its modified forms (polymer–TiO2), as well as the kinetics and mechanism of polymer molecule–sensitized TiO2 catalyst for the degradation of selected pharmaceutical organic pollutants. Finally, some of the photocatalytic degradation intermediates for the selected pharmaceuticals were reviewed.