Efficient photocatalytic mineralization of polymethylmethacrylate and polystyrene nanoplastics by TiO2/β-SiC alveolar foams

Household wastewaters contain microplastics and nanoplastics that end up in ecosystems because these pollutants are not filtered by current wastewater treatment plants. Therefore, there is a need for advanced removal technologies. Here, we tested the degradation of polymethylmethacrylate (PMMA) and polystyrene (PS) nanoparticles by photocatalysis with TiO2–P25/β-SiC foams under UV-A radiation. We studied the effect of flow rate, initial pH and light intensity. Results show that about 50% of the carbon of polymethylmethacrylate nanobeads are degraded in 7 h at an irradiance of 112 W/m2, a flow rate of 10 mL/min and an initial pH of 6.3. Degradation is faster at low pH (4–6) and low flow rate. 140-nm polystyrene degrades faster than 508-nm polystyrene.