Nitridation of BaO supported on mesoporous materials: Basicity characterization and catalytic properties

Nitridation has drawn much attention as a novel method to prepare solid base materials. In the present work, nitridation was employed to improve the basic property of BaO supported on mesoporous materials. Ba2SiO4 and Ba4Si6O16 basic species were formed after BaO loading on MCM-41 and SBA-15, respectively while only Ba2SiO4 species were observed both on MCM-41 and SBA-15 after nitridation. Basic species, bridging –NH– groups, were introduced into the framework of BaO-MCM-41/SBA-15 by nitridation with the mesoporous structure preserved. The surface basic property of obtained samples was analyzed by IR spectra using CDCl3 and CO2 as probe molecules and XPS. The enhancement in the surface basicity was observed after nitridation. Compared with BaO-MCM-41/SBA-15, the N-incorporated materials with stronger basicity exhibited higher activities in Knoevenagel condensation and the conversion of 2-propanol.

Nitridation was used to improve the surface basicity of BaO supported on MCM-41 and SBA-15 mesoporous materials. Obviously, the as-prepared mesoporous materials with stronger basicity exhibited better base catalytic results in the conversion of 2-propanol..Figure optionsDownload high-quality image (133 K)Download as PowerPoint slideResearch highlights▶ The surface basicity of BaO-MCM-41 and BaO-SBA-15 is improved by nitridation. ▶ The Ba2SiO4 and -NH- base species are formed on the surface after nitridation. ▶ BaO-MCM-41N and BaO-SBA-15N present enhanced basic catalytic properties.