Utilization of e-waste as a silica source for the synthesis of the catalyst support MCM-48 and highly enhanced photocatalytic activity of supported titania nanoparticles
An extensive range of studies has investigated the silica-supported TiO2 catalyst. However, research on cubic-type MCM-48 photocatalyst materials is limited. E-waste represents one of the fastest-growing sources of industrial waste worldwide. The present study reports, for the first time, direct synthesis of TiO2 nanoparticles loaded on MCM-48 deriving from e-waste. Alkali-extracted electronic packaging resin ash provided a source of sodium silicate precursors. Titanium salts were introduced into the pores of MCM-48 and subsequently decomposed to TiO2 nanoparticles. Methylene blue was used to evaluate the photoactivity of the hybrid catalyst at varying amounts of TiO2 loading, catalyst masses, and heat-treatment temperatures. Results indicated that TiO2/MCM-48 demonstrates a combined effect, including the photocatalytic activity of TiO2 along with the high adsorptive efficiency of MCM-48. Different ratios of titanium metal deposited on silica surfaces had significant influences on the porosity and adsorption properties of the MCM-48 support, as well as the dispersion, particle size, and catalytic activity of the TiO2 catalyst. Good dispersion of TiO2 on the MCM-48 support played a significant role in obtaining high photocatalytic activity. Synthesis of mesoporous photocatalysts from e-waste using a green approach can reduce the disposal problem and produce viable materials for a wide range of applications.
Graphical abstractPure titania reveals a very weak photocatalytic activity. MCM-48 plays a major role in adsorption of MB. The hybrid catalysts’ higher surface areas and adsorption capacities are significant factors in increased elimination of dye. Titania/MCM-48 has a higher photoefficiency than that of titania/silica-gel.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesis of mesoporous photocatalysts from e-waste. ► Titania/MCM-48 shows a combined effect of photoactivity with high adsorptive efficiency. ► The porosity and adsorption capacity of MCM-48 support is affected by titania ratios. ► Hybrid catalyst material has a high surface area of 1046 m2/g. ► Good dispersion of titania on MCM-48 support obtains high photocatalytic efficiency.
Journal: Applied Catalysis B: Environmental - Volumes 115–116, 5 April 2012, Pages 138–148