Imprinted Photocatalysts for Applications in Pollutant Removal from Water

Imprinted TiO2 nanoparticles using phenol derivatives as a template for the removal of organic
pollutants from wastewater were developed. Phenol was selected as a target pollutant. The
chemicals used are titanium (IV) oxide, 4-hydroxybenzoic acid, acetic acid, and ethanol. All
chemicals used were analytical grade and used as received without any further purification. Sol-
gel technique was used for the synthesis of photocatalysts. The mixed solution was stirred for
3 h, aged for 24 h, and dried at 100 °C for 1 h before calcination. The nanoparticles were then
calcined at 500, 550, and 600 °C, and their catalytic activity was compared with non-imprinted
TiO2. The imprinted TiO2 samples are named MITiO2@500 °C, MITiO2@550 °C, and
MITiO2@600 °C according to their calcination temperatures, while the non-molecular
imprinted Ti02 is named NMITiO2. The results showed that MITiO2@500 °C had the highest
removal efficiency (91.66-0.42%). For non-imprinted TiO2, the removal efficiencies at various
calcination temperatures were quite low (< 50%). This study revealed that the imprinting
technique was more effective in enhancing photocatalytic performance than the non-imprinting
technique. The optimum calcination temperature for both imprinted and non-imprinted
techniques was found to be 500 °C. Overall, imprinted TiO2 nanoparticles showed potential for
the removal of phenol from wastewater.