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Updated: Aug 14, 2026
09:37
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Core-Shell Ni/ZSM-5@SiO2 Bifunctional Catalysts for Enhanced n-Heptane Hydroisomerization via Regulated Metal-Acid
Xiuli Dong1, Zhuoyan Li1, Qinghua Du2
1College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing 163318, China.
Molecules (Basel, Switzerland)
|August 13, 2026
Summary
A novel core-shell catalyst enhances gasoline production by improving octane number and reducing aromatics. This bifunctional catalyst, Ni/ZSM-5@SiO2, optimizes n-heptane hydroisomerization for cleaner fuels.
Area of Science:
- Catalysis
- Materials Science
- Chemical Engineering
Background:
- Improving gasoline quality requires increasing octane number and decreasing aromatic content for cleaner fuel production.
- Bifunctional catalysts are essential for processes like n-heptane hydroisomerization, but often suffer from issues like undesired cracking.
- Designing catalysts with controlled acidity and pore structure is key to enhancing selectivity and conversion.
Purpose of the Study:
- To construct a core-shell bifunctional catalyst (2% Ni/ZSM-5-138@SiO2-1) for n-heptane hydroisomerization.
- To investigate the effect of an amorphous SiO2 shell on catalyst performance, particularly surface acidity and mass transport.
- To achieve high n-heptane conversion and isomer selectivity for clean fuel applications.
Main Methods:
- Synthesized a core-shell catalyst by coating ZSM-5 with SiO2, followed by Ni impregnation.
- Characterized the catalyst's structure, acidity, and pore properties.
- Evaluated the catalyst's performance in n-heptane hydroisomerization under optimized reaction conditions.
Main Results:
- The core-shell catalyst demonstrated an n-heptane conversion of 91.1% and an isomer selectivity of 56.7%.
- The SiO2 shell effectively regulated external surface acidity, preserved the ZSM-5 framework, and created a hierarchical pore structure.
- The catalyst design suppressed undesired cracking reactions, indicating improved metal-acid synergy and mass transport.
Conclusions:
- The core-shell architecture of Ni/ZSM-5@SiO2 provides a synergistic optimization of surface acidity, mass transport, and metal-acid cooperation.
- This catalyst design offers a practical strategy for developing efficient bifunctional catalysts for n-heptane hydroisomerization.
- The study contributes to the development of cleaner fuel production technologies through advanced catalyst design.
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