Hybrid carbon materials: Synthesis, characterization, and application in the removal of pharmaceuticals from water
Velma Beri Kimbi Yaah, Satu Ojala, Hamza Khallok, Tiina Laitinen, Sérgio Botelho de Oliveira
Abstract
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 CO 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.