TY - JOUR
T1 - Catalytic deactivation of HY zeolites in the dehydration of glycerol to Acrolein
AU - Pala-Rosas, Israel
AU - Contreras, José L.
AU - Salmones, José
AU - Zeifert, Beatriz
AU - López-Medina, Ricardo
AU - Navarrete-Bolaños, Juan
AU - Hernández-Ramírez, Sofía
AU - Pérez-Cabrera, Jennipher
AU - Fragoso-Montes De Oca, Andrés A.
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021
Y1 - 2021
N2 - The study of the deactivation of HY zeolites in the dehydration reaction of glycerol to acrolein has represented a challenge for the design of new catalysts. HY zeolites with SiO2/Al2O3 molar ratios between 3.5 and 80 were studied. The solids were characterized by XRD, N2 physisorption, SEM-EDXS, Raman and UV-vis spectroscopies, infrared spectroscopy of pyridine (FTIR-Py) and catalytic activity tests from 250 °C to 325 °C. It was found that the total amount of acid sites per unit area of catalyst decreased as the SiO2/Al2O3 molar ratio increased from 3.5 to 80, resulting in the decrease in the initial glycerol conversion. The initial acrolein selectivity was promoted with the increase of the Brønsted/Lewis acid sites ratio at any reaction temperature. The deactivation tests showed that the catalyst lifetime depended on the pore structure, improving with the presence of large surface areas as evidenced by the deactivation rate constants. The characterization of the deactivated catalysts by XRD, N2 physisorption and thermogravimetric analysis indicated that the deposition of coke resulted in the total obstruction of micropores and the partial blockage of mesopores. Moreover, the presence of large mesopores and surface areas allowed the amount of coke deposited at the catalyst surface to be reduced.
AB - The study of the deactivation of HY zeolites in the dehydration reaction of glycerol to acrolein has represented a challenge for the design of new catalysts. HY zeolites with SiO2/Al2O3 molar ratios between 3.5 and 80 were studied. The solids were characterized by XRD, N2 physisorption, SEM-EDXS, Raman and UV-vis spectroscopies, infrared spectroscopy of pyridine (FTIR-Py) and catalytic activity tests from 250 °C to 325 °C. It was found that the total amount of acid sites per unit area of catalyst decreased as the SiO2/Al2O3 molar ratio increased from 3.5 to 80, resulting in the decrease in the initial glycerol conversion. The initial acrolein selectivity was promoted with the increase of the Brønsted/Lewis acid sites ratio at any reaction temperature. The deactivation tests showed that the catalyst lifetime depended on the pore structure, improving with the presence of large surface areas as evidenced by the deactivation rate constants. The characterization of the deactivated catalysts by XRD, N2 physisorption and thermogravimetric analysis indicated that the deposition of coke resulted in the total obstruction of micropores and the partial blockage of mesopores. Moreover, the presence of large mesopores and surface areas allowed the amount of coke deposited at the catalyst surface to be reduced.
KW - Acrolein
KW - Glycerol dehydration
KW - HY zeolite
KW - Micro/mesoporous zeolites
KW - Zeolite acidity
KW - Zeolite deactivation
UR - http://www.scopus.com/inward/record.url?scp=85102239010&partnerID=8YFLogxK
U2 - 10.3390/catal11030360
DO - 10.3390/catal11030360
M3 - Artículo
AN - SCOPUS:85102239010
SN - 2073-4344
VL - 11
SP - 1
EP - 26
JO - Catalysts
JF - Catalysts
IS - 3
M1 - 360
ER -