(552e) Synthesis of Photocatalytic Hydrochars and Application of Emerging Contaminants Degradation

Hydrothermal carbonization of waste biomass has led to emergence of hydrochars – a porous carbon material – for environmental applications. We aim to improve hydrochar’s application in the field of water and wastewater treatment by creating a novel photocatalytic nanocomposite from deposition of homogeneously dispersed TiO₂ nanoparticles on hydrochar surface. This conjugated nanocomposite combines with important advantage of an excellent adsorbent i.e., hydrochar for emerging organic pollutant adsorption with the ability to degrade these contaminants by photocatalytic activity of TiO₂ nanoparticles. In this study, we prepared TiO₂ nanoparticles in situ during the hydrothermal carbonization of food waste. We studied the effect of temperature and precursor ratios (biomass:TiO₂ precursor) on the physicochemical properties of the synthesized hydrochar-TiO₂ nanocomposite. This was done using scanning electron microscopy (SEM) for physical morphology, electron dispersive spectroscopy (EDS) for elemental composition, and thermogravimetric analysis (TGA) for metal content. We studied the degradation of ibuprofen and carbamazepine – the two well-known pharmaceuticals present in wastewater. We found that the nanocomposites degrade these compounds much faster than the TiO₂ nanoparticles themselves under sunlight activation. The bandgap measurement shows that TiO₂ achieves visible light activity when conjugated with hydrochar and that contributes to the enhanced performance in the enhancement of contaminant degradation.