Removal of pharmaceuticals and endocrine disrupting chemicals by a submerged membrane photocatalysis reactor (MPR)

• Detailed assessment of removal kinetics for 33 trace organics.
• Eighteen compounds completely degraded after 1 h in photocatalytic reactor.
• Amide-based compounds were only moderately or slowly degraded.
• Flame retardant tris(2-chloroethyl) phosphate (TCEP) was not removed at all.
• Impact of the tested model water solution found to be not significant.

The photocatalytic degradation of 33 trace organics contaminants (TrOCs), including drugs, analgesics, antibiotics, surfactants or herbicides, has been evaluated using Aeroxide® P25 TiO2 treatment. Pseudo-first order reaction constants (k) of the TrOCs present in a complex mixture have been determined, rather than individually assessed, like in most of the previous studies. All the compounds except the flame retardant tris(2-chloroethyl) phosphate (TCEP), were eliminated by photocatalysis in different extends, with compounds containing amide groups being moderated or slowly degraded. Similar results were obtained during the continuous treatment of the TrOCs in a photocatalytic reactor comprised by suspended TiO2 and a submerged ultrafiltration (UF) hollow fiber membrane. Eighteen compounds were completely degraded after 1 h reaction, a group of 14 compounds showed removal percentages between 50% and 88% and TCEP was not eliminated at all. When the reaction was carried out using an organic-based model surface water containing the 33 TrOCs, percentage removals remained generally constant or slightly decreased by about 15%. Additionally, TrOCs adsorption into the membrane material and into the catalyst was analyzed. Hydrophobic compounds generally showed more tendency to be absorbed into the PVDF membrane.