Enhanced Photocatalytic Kinetics Using HDTMA Coated TiO2-Smectite Composite for the Oxidation of Diclofenac under Solar Light

Abstract

Slow kinetics is one of the capital issues of photocatalytic technology because of its heterogeneous nature, which involves multi-step processes. Herein, we show that the simple modification of the sol-gel-based TiO2-smectite composite by hexadecyltrimethylammonium bromide (HDTMA) significantly boosts adsorption and photocatalytic efficient sol-gel-based light towards the removal of diclofenac from water. Three photocatalysts were prepared, including TiO2, TiO2-smectite, and HDTMA-TiO2-smectite. The materials were characterized to understand the surface interaction and crystal characteristics. In terms of photoactivity, it was found that the addition of HDTMA to TiO2-smectite improved the removal rate by twice. HDTMA changes the functional groups to TiO2-smectite composite allowing enhanced adsorption and photoactivity through the so-called Adsorb and Shuttle process. The recycling tests show that HDTMA-TiO2-smectite can be used up to four times with good performance. This modification approach could intensify the removal of pollutants from water instead of using complicated and costly techniques.

Physicochemical analysis and detection of exceptionally high diclofenac concentration in the pharmaceutical wastewaters collected from the production units of national industrial zone, Rawat, Pakistan

“…Due to its excessive annual consumption of almost 940 tons all over the world, DCF has become a common and persistent water contaminant because of its high stability and hydrophobicity (Fellah et al 2022). The highest (38%) consumed pharmaceutical groups in Pakistan is nonsteroidal anti-inflammatory drug (NSAID) (Nasir et al 2012), and among the NSAID, DCF is the most popular pain killer due to its over-the-counter availability (Lonappan et al 2016).…”