Synthesis of Nb/MCM-48 material using rice husk ash as silica source with different SI/NB molar ratios

Abstract

The large amount of rice produced in Brazil generates a large volume of co-products, such as, Rice Husk (RH) and Rice Husk Ash (RHA). These co-products have amounts of silicon (Si) present in their structure, which can be used to synthesize silica-based materials as zeolites and MCM-type structures. The synthesis of MCM-48 material was carried out at room temperature, using the ionic liquid [C16MI·Cl] as structure-directing agent, depositing the niobium in situ during the synthesis with different molar ratios of Si/Nb (5, 20, 50 and 80). The material obtained was subjected to characterization by X-Ray Diffraction (XRD), Nitrogen Adsorption/Desorption isotherms and Scanning Electron Microscopy (SEM). The results confirm the formation of Nb/MCM-48 materials, in which their properties are consistent with those described in the literature. The deposition of Nb on MCM-48 did not change its structural properties, such as specific surface area and pore distribution for Si/Nb higher than 5. The results obtained demonstrate the success in the synthesis of mesoporous materials Nb/MCM-48 using industrial residues of rice as an alternative source of silicon, and in situ deposition of the niobium metal on the structure.

Opportunities and Challenges of Plant Bioactive Compounds for Food and Agricultural-Related Areas

“…For example, Rice Husk (RH) and Rice Husk Ash (RHA) can be used to synthesize silica-based materials into zeolites and MCM-type structures due to the silicon (Si) contained in these co-products. Pedott et al [130] demonstrated the synthesis of MCM-48 material using ionic liquid as a structure-directing agent employing Si obtained from RH and RHA. Moreover, MCMtype structures can be used in the immobilization of enzymes for use as catalysts in hydrolysis and esterification reactions [131].…”