Cerium modified Y/SBA-15 composite molecular sieve catalyzed synthesis of n-butyl acetate

• Published in: Journal of rare earths 2016-06, Vol.34 (6), p.597-603
• Main Author: 史春薇 吴文远 边雪 裴明远 赵杉林 陈平
• Format: Article
• Language: English
• Subjects: acetate; catalyst; Ce-modification; composite; earths; microporous-mesoporous; microporous-mesoporous composite molecular sieves; molecular; n-butyl; n-butyl acetate; rare; rare earths; sieves
• ISSN: 1002-0721; 2509-4963
• DOI: 10.1016/S1002-0721(16)60067-4

A novel Ce-Y/SBA-15 catalyst was prepared by modifying HY/SBA-15 microporous-mesoporous composite molecular sieve with cerium using the impregnation method. The characterization results from scanning electron microscopy/energy dispersive X-ray dispersive spectroscopy（SEM/EDS）, transmission electron microscopy（TEM）, and X-ray fluorescence（XRF） studies indicated that the Ce-modified catalyst maintained the microporous-mesoporous structure of Y/SBA-15. The Ce ions were found to be uniformly dispersed in the pores of the molecular sieve without aggregation. The results from pyrolysis coupled-Fourier transform infrared spectroscopy（Pyridine-FTIR） and temperature programmed desorption of ammonia（NH3-TPD） showed that the loading of cerium caused the hydroxyl group in the catalyst to display stronger Bronsted acidity. The efficiency of the modified Ce-Y/SBA-15 catalyst was evaluated by using it to catalyze the synthesis of n-butyl acetate. The optimal synthesis conditions were determined by orthogonal experiments. The highest esterification yield of 94.4% was obtained when the reaction time was 2.0 h, with acid/alcohol molar ratio of 1：1.2, and catalyst loading of 10 wt.%. The results in this study demonstrated that the loading of cerium and the structure of Y/SBA-15 microporous-mesoporous composite molecular sieve helped in improving the catalytic activity of this acidic catalyst.