Mesoporous Titanium-Silicalite Zeolite Containing Organic Templates as a Bifunctional Catalyst for Cycloaddition of CO2 and Epoxides

• DOI: 10.1021/acsami.8b04759
• Publication Date: 2018-06-13T09:34:57Z
• Authors: Dan Liu; Gang Li; Jiaxu Liu; Yue Wei; Hongchen Guo
• Keywords: Template

Mesoporous TS-1 (MTS-1) containing organic templates tetrapropylammonium hydroxide (TPAOH) and polydiallyldimethylammonium chloride is synthesized treated with different concentrations of hydrochloric acid aqueous solution. The as-synthesized MTS-1 are characterized using X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy, transmission UV-vis, 13C cross-polarization/magic angle spinning (CP/MAS) NMR, thermogravimetry analysis, CO2-temperature-programmed desorption (TPD), N2 adsorption-desorption, fluorescence, elemental analysis. results CP/MAS NMR show that the structures retained after washing treatment. Not required to be removed by calcination, embedded in can take role basic sites activate carbon dioxide (CO2), which confirmed FT-IR. Moreover, amount samples before treatment modified Hammett indicator method CO2-TPD, respectively. both acidity basicity material improved washing. Thus, sample contains two active sites: stemming from species coming framework Ti, beneficial used as a bifunctional catalyst cycloaddition reaction CO2 epoxides. It highly reaction, conversion epichlorohydrin (ECH) could reach 97.8% selectivity cyclic carbonate 98.0% under 1.6 MPa at 393 K for 6 h when acetonitrile solvent. kinetics studied ECH substrate varying parameters. More importantly, organic-inorganic hybrid reusable stable against leaching reaction.