The Role of Denitration Catalysts  

Denitration catalysts are essential for reducing environmental pollution by converting nitrogen oxides (NOx) in flue gas into harmless nitrogen (N₂) and water (H₂O). These catalysts are widely used across industries, including coal-fired power plants, chemical facilities, gas boilers, rail systems, and automotive exhaust treatment.  

 

Composition of Denitration Catalysts  

Commercial SCR catalysts are primarily composed of:  

- TiO₂ as the support material.  

- V₂O₅ as the main active component.  

- WO₃ and MoO₃ as additives to improve oxidation resistance and prevent catalyst poisoning.

Catalysts are manufactured in three main configurations:  

1. Plate-type catalysts: A mixture of TiO₂ and V₂O₅ is applied to stainless steel mesh, pressed, sintered, and assembled into modular units.  

2. Honeycomb-type catalysts: A homogeneous mixture of TiO₂, V₂O₅, and WO₃ is extruded by a ceramic extrusion device into a honeycomb structure and then sintered.
3. Corrugated plate-type catalysts: Glass fiber-reinforced TiO₂ as the base material, with active components like WO₃ and V₂O₅ impregnated onto the surface to enhance catalytic activity and minimize SO₂ oxidation.  

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Application of EDXRF Method with Fused Bead Preparation in Analyzing Denitration Catalyst Components 

Equipment

- EDXRF Spectrometers: XRF2501/XRF 2501(*Integrated) / XRF2510.  

- Fusion Machines: HF3000 / HF3200 / HF3400 / AFM3600 / FM3500.  

- Reagents: Flux and releasing agents.  
Sample Preparation Process  

1. Weigh a dried catalyst powder sample (dried at 105°C) and mix it with a flux in a platinum crucible.  

2. Place the crucible into the fusion machine, which automatically processes the sample at high temperatures to produce a homogeneous glass beads ideal for XRF analysis.  

Creating Calibration Curves

1. Prepare glass beads for calibration using the fusion machine.  

2. Analyze the beads using the XRF spectrometer to create calibration curves.  

- Performance: The linear correlation coefficients (R²) for all calibration curves exceed 0.99, ensuring exceptional accuracy and reliability.  

Samples Results  

After the calibration curves had been created, multiple samples of denitration catalysts were analyzed. The test results are as follows (%):

Sample	MgO	Al₂O₃	SiO₂	P₂O₅	SO₃	CaO	TiO₂	V₂O₅	Fe₂O₃	MoO₃	WO₃
1	0.16	2.71	5.21	7.51	0.43	1.14	78.12	0.31	0.16	-	4.27
2	0.31	1.2	5.84	-	/	1.12	78.49	5.65	4.04	2.62	-
3	0.45	3.83	9.12	-	1.18	2.02	79.41	0.92	0.57	-	2.72
4	0.32	2.38	9.48	-	1.7	2.07	78.76	0.8	0.68	-	4.14
5	0.54	1.24	5.64	-	0.45	1.57	87.18	0.52	0.18	-	2.32
6	0.16	1.88	7.9	-	0.98	1.63	82.12	0.67	0.48	-	4.16
7	0.45	2.26	9.35	-	0.97	1.92	79.72	1.48	0.92	-	2.73

Key findings include:  

- High accuracy: The method delivers precise determinations of components such as MgO, Al₂O₃, SiO₂, P₂O₅, SO₃, CaO, TiO₂, V₂O₅, Fe₂O₃, MoO₃, and WO₃.  

- Operational efficiency: The process is simple, highly automated, and fast, meeting the demands of industrial production for rapid and accurate analysis.