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Synthesis of Bimetallic Pt/Sn-based Nanoparticles in Ionic Liquids
Published on: August 23, 2018
[Selective reduction of NO over indium catalysts prepared by different methods]
Xiang-yu Cui1, Ji-ming Hao, Lin-xin Fu
1Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue= Huanjing Kexue
|May 12, 2006
Summary
Alumina-supported indium catalysts show high activity for nitrogen oxide (NOx) reduction. Preparation methods significantly impact performance, with co-precipitation and sol-gel methods yielding superior results compared to impregnation.
Area of Science:
- Catalysis
- Materials Science
- Environmental Chemistry
Context:
- Selective Catalytic Reduction (SCR) is crucial for controlling nitrogen oxide (NOx) emissions.
- Developing efficient and cost-effective catalysts for NOx reduction is an ongoing challenge.
- Indium-based catalysts are explored as alternatives to traditional NOx reduction catalysts.
Purpose:
- To synthesize and characterize alumina-supported indium catalysts (In/Al2O3) using impregnation, co-precipitation, and sol-gel methods.
- To evaluate the catalytic activity of these In/Al2O3 catalysts for the selective catalytic reduction of NOx by propene in excess oxygen.
- To investigate the influence of preparation methods, oxygen concentration, and water presence on catalyst performance.
Summary:
- Alumina-supported indium catalysts prepared via co-precipitation or sol-gel methods demonstrated high NOx conversion (around 90%) in SCR reactions.
- Impregnation method resulted in significantly lower activity (below 60% conversion).
- Optimal indium loading was consistently around 1-2% across all preparation methods, a unique characteristic for indium catalysts.
Impact:
- Co-precipitation and sol-gel synthesis routes are identified as superior for preparing active In/Al2O3 SCR catalysts.
- Oxygen concentration in the feed gas affects NOx reduction efficiency and reaction temperature, with higher O2 levels lowering the required temperature.
- Water in the feed gas significantly inhibits the deNOx activity of In/Al2O3 catalysts, highlighting the need for dry reaction conditions.
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