Photocatalytic degradation of methylene blue by a combination of TiO2-anatase and coconut shell activated carbon

TiO2-anatase is obtained directly by chemical vapor condensation (T-95), or from a commercial catalyst (P-25). TiO2 nanoparticles and coconut shell activated carbon, CSAC, are mixed with mass ratios of 1/1 (CT-1, CP-1) and 2/1 (CT-2, CP-2), respectively. These nanomaterials are characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) surface area, and X-ray photoelectron spectroscopy (XPS). The catalyst obtained from the CVC process is better than the commercial one in a comparison of the physico-chemical properties, and was also confirmed by the photocatalytic degradation of methylene blue (MB). The composited catalysts (CSAC/TiO2) are better than CSAC or naked TiO2 only. At the same TiO2 to CSAC mass ratio, the MB removal efficiencies followed the trend: CT-2 > CT-1 > CP-2 > CP-1 > T-95 > CSAC > P-25. Furthermore, the advantages of the CT-2 catalyst revealed its practical potential to treat pollutants.

Graphical abstractTiO2 nanocatalyst obtained from CVC process (T-95) is better than the commercial one (P-25) in terms of physico-chemical properties. TiO2-anatase nanoparticles and coconut shell activated carbon (CSAC) are mixed with mass ratios 1:1 or 2:1. The MB degradation efficiencies followed the trend: CT-2 > CT-1 > CP-2 > CP-1 > T-95 > CSAC > P-25.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► TiO2 anatase (T-95) was synthesized by chemical vapor condensation. ► T-95 and P-25, were modified with coconut shell activated carbon (CSAC). ► The materials were characterized by XRD, TEM, BET surface area, and XPS. ► The catalysts were used to check their photocatalytic activity using methylene blue. ► Observed removal efficiencies follow the order: CT-2 > CT-1 > CP-2 > CP-1 > T-95 > CSAC > P-25.