Evaluating pore characteristics and acid site locations in hierarchical SAPO-11 by catalytic model reactions

Pinpointing basic sites formed upon incorporation of iron in hierarchical SAPO-11 using catalytic model reactions

“…These surface areas also correspond to previous studies on non-metal-containing conventional SAPO-11 and hierarchical SAPO-11 synthesized with CTAB as a meso-SDA, where a comparison to a reference conventional SAPO-11 without metal (C-SAPO-11) has been provided in the ESI, Table S1-2. † 10,19,28 The micropore volumes of the SAPOs in this study were comparable (∼0.07 cm 3 g −1 ), whereas FeCTAB-11 had a much larger mesopore volume (0.13 cm 3 g −1 ) than FeSAPO-11 (0.06 cm 3 g −1 ). The micropore volumes were in accordance with previous literature reports, 28,29 whereas the mesopore volumes for both the conventional FeSAPO-11 and the hierarchical FeCTAB-11 were in the lower range of previous studies on non-metal-containing SAPO-11 systems.…”

“…The vapor phase Beckmann rearrangement of cyclohexanone oxime was carried out in a vertical tube reactor (ID: 4 mm) attached to a condenser as described by previous reports. 19 By applying chlorobenzene (99%, Sigma Aldrich) as an internal standard, the obtained liquid products were identified and analyzed with a gas chromatograph equipped with a flame ionizing detector (FID) coupled to a mass spectrometer (GC-MS, Agilent 7890A coupled to an Agilent 5975C inert XL MSD).…”

“…The calibration, conversion, selectivity and mass balance calculations were carried out in accordance to previous reports. 18,19 3. Results & discussion…”

“…12,29 Notably however, both the micropore and mesopore volumes matched a previous study on the hydrothermal synthesis of conventional SAPO-11 and hierarchical SAPO-11 with CTAB as a meso-SDA, where a comparison to the former has been included in the ESI, Table S1-2. † 19 The nitrogen physisorption isotherms of the FeSAPOs are displayed in Fig. 3A, whereas a comparison to a reference C-SAPO-11 has been provided in the ESI, Fig.…”

“…17,18 Likewise, the corresponding properties of the low acid density hierarchical SAPO-11 (10-membered ring, 0.4 nm × 0.6 nm pore apertures) 17 were successfully investigated by using the vapor phase isomerization of cyclohexanone oxime (Beckmann rearrangement, BMR) model reaction. 19 With this work, we wish to demonstrate the versatility of the previously introduced model reactions by probing the pore connectivity and location of transition metal sites in a metal-incorporated hierarchical SAPO model system.…”