Low-temperature synthesis of hierarchical architectures of SAPO-11 zeolite as a good hydroisomerization support
Source abstract
Abstract
Hierarchical SAPO-11 was successfully synthesized without a secondary template by changing the hydrothermal crystallization temperature. SAPO-11 with a larger external surface area, more acidity, and a large number of external active sites was constructed through a novel two-step crystallization strategy. Both precrystallization step and the low-temperature crystallization step were confirmed to be indispensable conditions for constructing hierarchical SAPO-11. After loading Pt nanoparticles by incipient wetness impregnation, the heptane hydroisomerizations based on 0.5 wt% Pt/C-SAPO-11-200 and 0.5 wt% Pt/T-SAPO-11-120 catalysts were carried out in a fixed-bed at a total pressure of 1.5 MPa with a H2/n-heptane volumetric of 400 and WHSV = 10 h−1. A conversion level of 75.7% of 0.5 wt% Pt/T-SAPO-11-120 catalyst was reached, which was higher than that of 0.5 wt% Pt/C-SAPO-11-200 catalyst (64.3%) at 300 °C. The enhanced performance achieved was attributed to the improved effect of the support, in terms of not only better mass transport and higher number of exposure active sites but also improved dispersity and decrease in the size of Pt particles.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Zeolite Catalysis and Synthesis · Metal-Organic Frameworks: Synthesis and Applications · Chemical Synthesis and Characterization
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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