摘要
Titanosilicate pillared MFI zeolite nanosheets were successfully synthesized by infiltrating the mixed tetraethyl orthosilicate(TEOS)/tetrabutyl orthotitanate(TBOT)solvent into the gallery space between adjacent MFI zeolite layers.The obtained zeolite catalysts were characterized using powder X-ray diffraction,N2 adsorption/desorption isotherms,scanning electron microscopy,transmission electron microscopy,ultraviolet-visible spectroscopy,X-ray photoelectron spectroscopy,and Fouriertransform infrared spectroscopy techniques.The H2〇2 oxidation of dibenzothiophene(DBT)was used to evaluate the catalytic performance of the obtained titanosilicate pillared MFI zeolites.The conversion of DBT and selectivity of dibenzothiophene sulfone(DBTS)were most affected by the textural properties of the zeolites.This was attributed to the DBT and DBTS molecules being larger than micropores of the MFI zeolites.The conversion of DBT and yield of DBTS could be systematically tailored by tuning the molar ratio of the TEOS/TBOT solvent.These results implied that a balance between the meso-and microporosity of zeolites and tetrahedrally coordinated Ti(IV)active sites of titanosilicate pillars can be achieved for the preparation of desired catalysts during the oxidation of bulk S compounds.
基金
This work was funded by the National Natural Science Foundation of China(Grant Nos.21808040,51476176,and 21776049)
The support of the Science and Technology Program of Guangzhou,China(Grant No.201804010172)is also gratefully acknowledged.