Photocatalytic degradation of acetaminophen in aqueous solution by Zn _0.2 Cd _0.8 S catalyst and visible radiation

Photocatalytic degradation of acetaminophen in aqueous solution by Zn _0.2 Cd _0.8 S catalyst and visible light radiation was carried out under optimized conditions. The degradation was monitored spectrophotometrically. The degraded products were analyzed by gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry (LC–MS) and their structures were proposed using tandem mass spectrometry data. Various mechanistic pathways were observed involving ^• OH radicals. The parent compound was converted to lower molecular weight unsaturated carboxylic acids in addition to pyridine derivatives. Based on LC–MS and tandem mass spectrometry MS/MS results, a photocatalytic oxidative mechanism was suggested.