Hybrid carbon materials: Synthesis, characterization, and application in the removal of pharmaceuticals from water

Hydrothermal carbonization was used to develop novel carbon-based hybrids for the removal of diclofenac and amoxicillin from water. These non-crystalline and partly graphitic materials can be regenerated by photocatalysis. The synthesized materials have beneficial oxygen containing surface functional groups, of which C--O were observed only for tungsten-containing hybrid. An interaction between W, C and TiO2 was observed, which could influence the photocatalytic performance. The best performance was observed for W-containing hybrid (HC butox W) at pH 3 (diclofenac photocatalytic degradation of 80% and removal of 93% after 60 min). Significant part of the removal appeared due to precipitation of diclofenac on the hybrid material surface. Removal efficiency was fully recovered after regeneration at pH 7 under uv-B irradiation. With the same hybrid, 10% removal of amoxicillin after 30 min with 42% photocatalytic degradation at non-adjusted pH was reached. In general, tungsten improved the photocatalytic activity of material, while specific surface area played only a minor role.