“…Many other reactor configurations are described in the technical literature, including microreactors, rotating annular reactors, closed-loop reactors, among many others [26,149,150]. It is also worth mentioning the utilization of photoreactors with parabolic deflectors to enhance the incidence of light and increase the photocatalytic activity, especially in solar photocatalytic applications [151]. The selection of the photoreactor depends on several factors, including the pollutant to be removed, its concentration, the volume of water to be treated, the type of radiation (lamps or real sunlight), and, of course, the budget.…”