Hybrid polymer aerogels containing porphyrins as catalysts for efficient photodegradation of pharmaceuticals in water

Polymer aerogels of poly(acrylic acid)/poly(vinyl alcohol) (labeled as CPA) were prepared and tested as support materials for different cationic porphyrin organocatalysts (denoted as TMPyP, TMPyPZn, or TMPyPMn). The hybrid aerogels were characterized by various techniques, while their catalytic activity was investigated towards the photodegradation of amoxicillin (AMX), caffeine (CAF), and naproxen (NPX) under artificial visible light. Photodegradation experiments revealed that the CPA-TMPyPMn aerogel shows superior catalytic potential when compared to the others aerogels or the “free” TMPyPMn porphyrin. All pharmaceuticals were quickly degraded (before 60 min) and high COD removal rates (greater than95%) were achieved at pH 7.0 and room temperature. The CG-MS data confirm the complete degradation of all tested pharmaceuticals catalyzed by CPA-TMPyPMn. Recycling experiments revealed that this hybrid aerogel keeps its photocatalytic efficiency for at least 15 reuse runs. In short, this original photocatalytic system is promising to mediate the removal of pharmaceutical contaminants from the aqueous medium.