Effect of surface modification with silica on the structure and activity of Pt/ZSM-22@SiO2 catalysts in hydrodeoxygenation of methyl palmitate

Crystal‐size–dependent external surface diffusion barriers in Pt/ZSM‐5 catalyzed n‐pentane isomerization

“…The BAS numbers measured at 673 K (Py‐H + [673 K]) can be regarded as the number of strong BAS, and Py‐H + (673 K) for Z5‐S and Z5‐L decrease by 26.1% and 7.4% after SiO 2 deposition. Apparently, SiO 2 deposition on external surface of ZSM‐5 crystals can passivate BAS, which is also supported by other works 50–52 …”

“…Z5-L possesses more BAS and LAS than Z5-S, which is consistent with the result obtained from NH 3 -TPD curves and can also be attributed to the lower Si/Al ratio of Z5-L. BAS sites are believed to be the active sites for n-pentane isomerization, and the number of BAS can be directly correlated to the catalytic performance. 37,46 The BAS numbers mea- [50][51][52] To give a direct proof of SiO 2 deposition on ZSM-5 crystals, FTIR spectra are compared for parent and modified samples (Figure 6D).…”

Template Guiding for the Encapsulation of Uniformly Subnanometric Platinum Clusters in Beta‐Zeolites Enabling High Catalytic Activity and Stability

“…Generally, for noble-metal/zeolite as a catalyst to realize efficient HDO of phenolics, both of active metal sites and acid sites of support are important. [16] Guaiacol goes through sequenced hydrogenation (associated with metal) followed by deoxygenation (associated with acid sites) to form cyclohexane (Figure S15), consistent with those in literatures. [17] The original Pt@beta gave a guaiacol conversion of only 18.6 % (Figure S16), demonstrating the low catalytic activity of Pt@beta due to the weakened acidities, confirmed by ammonia temperature-programmed desorption experiments (NH 3 -TPD, Figure S17).…”

Correlated super-resolution fluorescence and electron microscopy reveals the catalytically active nanorods within individual H-ZSM-22 zeolite particles

“…In n-alkane hydroisomerization, for example, this would deteriorate catalyst shape selectivity. [37,38] The molecular confinement of the individual fluorescent reaction products with respect to the H-ZSM-22 crystals and the underlying pore structure was investigated using linear polarized excitation light. Note that the fluorescent FFA oligomers will only be efficiently excited when its dipole moment is oriented parallel to the polarization of the excitation light.…”