TY - JOUR
T1 - Synthesis of SAPO-18 with low acidic strength and its application in conversion of dimethylether to olefins
AU - Hirota, Yuichiro
AU - Yamada, Mayuka
AU - Uchida, Yoshiaki
AU - Sakamoto, Yasuhiro
AU - Yokoi, Toshiyuki
AU - Nishiyama, Norikazu
N1 - Funding Information:
This work was financially supported in part by CREST program from Japan Science and Technology Agency (JST). Authors are grateful to Mr. Shigeru Tamiya (Center for Scientific Instrument Renovation and Manufacturing Support, Osaka University) for ICP analysis. The TEM measurements were carried out by using a facility in the Research Center for Ultrahigh Voltage Electron Microscopy, Osaka University.
Publisher Copyright:
© 2016 Elsevier Inc. All rights reserved.
PY - 2016/9/15
Y1 - 2016/9/15
N2 - SAPO-18 molecular sieve was synthesized by a dry gel conversion (DGC) and hydrothermal (HT) synthesis methods using methyltriethoxysilane as the only Si source (DGC-Me-SAPO-18 and HT-Me-SAPO-18). Their physicochemical and catalytic properties on dimethylether-to-olefin (DTO) reaction were compared with those of conventional SAPO-18 molecular sieves synthesized by a hydrothermal synthesis method (HT-SAPO-18). An NH3-TPD measurement revealed that the desorption peak position of Brønsted acid of the Me-SAPO-18 samples moved to lower temperature, indicating that Brønsted acidic strength of the Me-SAPO-18 samples was lower than that of the HT-SAPO-18 samples. The DME conversions and yields of light olefins over DGC-Me-SAPO-18 decreased at a slower rate than those of HT-SAPO-18. The decreased acidic strength and flake-like morphology of DGC-Me-SAPO-18 could retard the coke formation, leading to the prolonged catalytic lifetime.
AB - SAPO-18 molecular sieve was synthesized by a dry gel conversion (DGC) and hydrothermal (HT) synthesis methods using methyltriethoxysilane as the only Si source (DGC-Me-SAPO-18 and HT-Me-SAPO-18). Their physicochemical and catalytic properties on dimethylether-to-olefin (DTO) reaction were compared with those of conventional SAPO-18 molecular sieves synthesized by a hydrothermal synthesis method (HT-SAPO-18). An NH3-TPD measurement revealed that the desorption peak position of Brønsted acid of the Me-SAPO-18 samples moved to lower temperature, indicating that Brønsted acidic strength of the Me-SAPO-18 samples was lower than that of the HT-SAPO-18 samples. The DME conversions and yields of light olefins over DGC-Me-SAPO-18 decreased at a slower rate than those of HT-SAPO-18. The decreased acidic strength and flake-like morphology of DGC-Me-SAPO-18 could retard the coke formation, leading to the prolonged catalytic lifetime.
KW - Brønsted acid strength
KW - Dimethylether-to-olefin (DTO) reaction
KW - Dry gel conversion
KW - SAPO-18
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U2 - 10.1016/j.micromeso.2016.06.009
DO - 10.1016/j.micromeso.2016.06.009
M3 - Article
AN - SCOPUS:84974782975
VL - 232
SP - 65
EP - 69
JO - Zeolites
JF - Zeolites
SN - 1387-1811
ER -