Photodegradation of paracetamol in montmorillonite KSF suspension followed the Langmuir–Hinshelwood kinetic model. The influence
of KSF dosage, initial paracetamol concentration, initial pH, chelating agents and a radical scavenger on the degradation
of paracetamol were studied and described in detail. The degradation mechanism of paracetamol was also proposed in this work.
The adsorption and photodegradation behavior of tetracycline (TC), chloramphenicol (CAP) and sulfamethoxazole (SMX) in clay mineral dispersion was investigated in this work. Only TC showed significant adsorption to natural montmorillonite and rectorite, whereas CAP and SMX adsorbed to natural montmorillonite, kaolinite and rectorite to a much lower extent. The adsorption equilibrium constants (L/kg) of TC to natural montmorillonite were 332 and 108 at pH 3.0 and 7.0, respectively. The kinetic rate constant kapp (min−1) for the removal of CAP in the presence of different clay minerals follows the sequence: montmorillonite KSF (1.6 × 10−2) > rectorite (4.6 × 10−3) > natural montmorillonite (3.8 × 10−3) > kaolinite (2.8 × 10−3). Removal of SMX follows the same sequence. Oxalate significantly promotes the removal of CAP and SMX in montmorillonite KSF dispersion, while penicillamine (PEN) and β-cyclodextrin retard the diminution. After 3 h of irradiation in 5 g/L KSF dispersion, the total organic carbon was reduced by 72 and 39% for CAP and SMX, respectively.
The degradation of acetaminophen (APAP) in aqueous solutions with heterogeneous Fenton reactions was investigated with montmorillonite
KSF as catalyst. The influencing factors of the initial APAP concentration, initial pH value, initial KSF dosage and H2O2 dosage were studied. The results showed that APAP could be effectively degraded under the conditions of pH 4.0, KSF 0.2 g/L
and H2O2 0.5 mM, and the degradation efficiency of 0.5 mg/L APAP reached 93.5% after reaction for 30 min. The degradation kinetics
of APAP followed the pseudo first-order rate law.