Acidic and Structure Characterization of Ce-MCM-41 MesoporousMolecular Sieve with Different Ratio of Silicon to Cerium
1. College of Chemistry and Chemical Engineering of Qiqihar University, Qiqihar 161006, China; 2. College of Chemical Engineering, Huaihai Institute of Technology, Lianyungang 222005, China
Abstract Ce-MCM-41 mesoporous molecular sieve with different silicon to cerium ratio(Si/Ce) was synthesized by hydrothermal method. The surface acidity, mesoporous structure, and chemical state of cerium were characterized by X-ray diffraction(XRD), NH3 temperature programmed desorption(NH3-TPD), pyridine adsorption infrared spectrum(PY-IR), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS) and N2 adsorption-desorption. The results indicated that when Si/Ce molar ratio drops from 150 to 30, the Ce-MCM-41 mesoporous molecular sieve exhibited the typical hexagonal mesoporous structure with both Lewis and Bronsted acid sites on the catalyst surface; when Si /Ce molar ratio declined further to 10, the ordered structure of the molecular sieve was partially diminished with mainly Bronsted acid on the catalyst surface. The Ce element introduced to the molecular sieve was in the form of Ce3+ and Ce4+ valence state with predominantly the positive quadrivalence.
He Xifeng 1,Song Weiming 2,An Hong 2. Acidic and Structure Characterization of Ce-MCM-41 MesoporousMolecular Sieve with Different Ratio of Silicon to Cerium[J]. 化学反应工程与工艺, 2013, 29(2): 164-169.
He Xifeng 1,Song Weiming 2,An Hong 2. Acidic and Structure Characterization of Ce-MCM-41 MesoporousMolecular Sieve with Different Ratio of Silicon to Cerium[J]. 化学反应工程与工艺, 2013, 29(2): 164-169.
