Water treatment: Mn-TiO2 synthesized by ultrasound with increased aromatics adsorption.

Pharma-products are mostly single or multiple cyclic compounds. They pollute surface water and are persistent in the aquatic ecosystem. When irradiated by UV light, TiO2 catalysts cleave or degrade organic contaminants in water. Removal of organics by photocatalysis results from a synergistic effect of adsorption and photocatalysis. Synthesis of catalysts by ultrasound (US) produces high surface area and porous solids. Here, we synthesized Mn-doped TiO2 with a US-assisted sol-gel method. Compared to the classical synthesis, US increased the BET surface area from 83 m2 g-1 to 90 m2 g-1 in the Mn-TiO2 sample and from 9.0 m2 g-1 to 53 m2 g-1 in the control TiO2. Accordingly, acetaminophen and amoxicillin adsorption increased from 44% to 52%, and from 34% to 94% for the Mn-TiO2 obtained in absence and presence of US, respectively. When in a mixture, the two drugs strongly compete for adsorption on TiO2.