Effective removal of paracetamol in compound parabolic collectors and fixed bed reactors under natural sunlight

Abstract Removal of persistent organic pollutants from water is quite challenging using biological treatment processes in waste water treatment plants. In order to improve the wastewater treatment quality for water reuse, many techniques are developed and the most commonly used is heterogeneous photocatalysis. This work studies the degradation of paracetamol (PAR), which is one of the most persistent pharmaceutical drugs in water, and widely used as an analgesic and antipyretic drug in Algeria. The paracetamol degradation has been carried out via heterogeneous photocatalysis, in a suspended solution of catalyst using a Compound Parabolic Collectors (CPC) reactor and in a fixed bed with immobilized catalyst under natural solar radiation. The degradation performance has been studied under various parameters such as substrate concentration and pH of solution. The degradation efficiency decreased when the initial paracetamol concentration increased from 2.5 mg/L to 20 mg/L. In addition, the selected reactors were found to be competent for the paracetamol degradation with an almost 98–99% removal of PAR. For the CPC reactor with suspended TiO2, the paracetamol elimination reached 98% after 300 min; however, for the fixed-bed reactor, TiO2 immobilized on cellulose-based paper was utilized, which yielded an almost 99% reduction in the PAR concentration after 90 min only of solar irradiation.