Towards sustainable PMR for organic contaminant removal from municipal wastewater

Abstract

Persistent organic pollutants (POPs) are dangerous for the human body and for the environment, due to their high chemical stability at low concentrations and low biodegradability. Traditional treatment plants are inadequate or inefficient, making their removal from water very difficult. Unlike most existing studies that rely on synthetic wastewater, the novelty of this work lies in studying the photocatalytic degradation of POPs in real urban wastewater using titanium dioxide-based slurry reactors. A distinctive contribution of this work also lies in the comparison of two reactor configurations (internal vs. external UV sources), supported by finite element modelling (FEM) to simulate and optimize light distribution. The results showed that the configuration with an immersed lamp, which ensures better light distribution, leads to enhanced catalytic activity at lower photocatalyst concentration and low light power. This optimal configuration was subsequently applied in a slurry photocatalytic membrane reactor (SPMR), resulting in improved pollutant removal efficiency. In particular, experimental results demonstrated that using an inorganic membrane with a molecular weight cut-off of 1 kDa achieved approximately a 15% increase in pollutant removal efficiency. This integrated, experimentally validated approach addresses a critical gap in translating lab-scale photocatalysis research to real wastewater treatment.