Preparation and NOx Reduction Performance of Ag-Ni-TiO2/Cordierite Catalyst for HC-SCR System

Year 2024, Volume: 39 Issue: 2, 339 - 347, 11.07.2024

Himmet Özarslan

https://doi.org/10.21605/cukurovaumfd.1514048

Abstract

Selective catalytic reduction (SCR) technology in diesel engines is an exhaust after treatment system used for abatement of nitrogen oxide (NOx) emissions. In order to synthesize Ag-Ni-TiO2/Cordierite catalyst in the conducted study, a solution including silver nitrate (AgNO3), titanium dioxide (TiO2), and nickel (II) nitrate hexahydrate (Ni(NO3)2·6H2O) were used in the coating of the cordierite (2Al2O3-5SiO2-2MgO) main carrier structure. The prepared catalyst was characterized for morphological characteristics via scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) analysis. The NOx reduction measurements as catalytic was carried out at 20 °C intervals in the temperature range from 190 to 270°C at 1 kW and 3 kW motor loads and under 30000 h−1 space velocity (SV). Ethanol was used as a reductant during the experiments. As a results of the measurements, it was seen that the Ag-Ni-TiO2/Cordierite catalyst exhibited a good NOx conversion efficiency with 93.8 % at 270°C at 3 kW.

Keywords

Selective catalytic Reduction, Catalyst, Cordierite, NOx emission

HC-SCR Sistemi için Ag-Ni-TiO2/Kordiyerit Katalizörünün Hazırlanması ve NOx İndirgeme Performansı

Abstract

Dizel motorlardaki seçici katalitik indirgeme (SCR) teknolojisi, nitrojen oksit (NOx) emisyonlarının azaltılması için kullanılan bir egzoz son arıtma sistemidir. Yapılan çalışmada Ag-Ni-TiO2/Kordiyerit katalizörünü sentezlemek amacıyla kordiyerit (2Al2O3-5SiO2-2MgO) ana taşıyıcı yapının kaplanmasında gümüş nitrat (AgNO3), titanyum dioksit (TiO2) ve nikel (II) nitrat hekzahidrat (Ni(NO3)2·6H2O) içeren bir çözelti kullanıldı. Hazırlanan katalizör, taramalı elektron mikroskobu (SEM) ve enerji dağılım spektroskopisi (EDS) analizi yoluyla morfolojik özellikler açısından karakterize edildi. Katalitik olarak NOx azaltım ölçümleri, 190 ila 270 ᵒC sıcaklık aralığında 20ᵒC aralıklarla, 1 kW ve 3 kW motor yüklerinde ve 30000 h-1 alan hızında (SV) gerçekleştirildi. Deneyler sırasında indirgeyici olarak etanol kullanıldı. Yapılan ölçümler sonucunda Ag-Ni-TiO2/Kordiyerit katalizörünün 270ᵒC'de 3 kW'ta %93.8 ile iyi bir NOx dönüşüm verimi sergilediği görülmüştür.

Keywords

Seçici katalitik indirgeme, Katalizör, Kordiyerit, NOx emisyonu

References

• 1. Boningari, T., Smirniotis, P.G., 2016. Impact of Nitrogen Oxides on the Environment and Human Health: Mn-based Materials for the NOx Abatement. Current Opinion in Chemical Engineering, 13, 133-141.
• 2. Kampa, M., Castanas, E., 2008. Human Health Effects of air Pollution. Environmental Pollution, 151, 362-367.
• 3. Kagawa, J., 2002. Health Effects of Diesel Exhaust Emissions-A Mixture of Air Pollutants of Worldwide Concern. Toxicology, 181-182, 349-353.
• 4. Busca, G., Lietti, L., Ramis, G., Berti, F., 1998. Chemical and Mechanistic Aspects of the Selective Catalytic Reduction of NOx by Ammonia over Oxide Catalysts: A Review. Applied Catalysis B: Environmental. 18, 1-36.
• 5. Dumestic, J.A., Topsøe, N.Y., Topsøe, H., Chen, Y., Slabiak, T., 1996. Kinetics of Selective Catalytic Reduction of Nitric Oxide by Ammonia over Vanadia/Titania. Journal of Catalysis, 163, 409-417.
• 6. Thirupathi, B., Smirniotis, P.G., 2012. Nickel-doped Mn/TiO2 as an Efficient Catalyst for the Low-temperature SCR of NO with NH3: Catalytic Evaluation and Characterizations. Journal of Catalysis. 288, 74-83.
• 7. Ning, S., Kashif, M., Deng, W., Zhao, B., Su, Y., 2024. Reactivity of Ni-modified MIL-100(Fe) Catalysts for C3H6-SCR and Reaction Mechanism. Catalysis Communications, 187, 106854.
• 8. Ning, S., Su, Y., Yang, H., Zhao, B., 2024. Ni-Modified MIL-100(Fe) Catalysts for CO-SCR of NO and Reaction Mechanism. Fuel, 359, 130452.
• 9. Shi, Y., Chu, Q., Xiong, W., Gao, J., Huang, L., Zhang, Y., Ding, Y., 2021. A New Type Bimetallic NiMn-MOF-74 as an Effcient Low-temperatures Catalyst for Selective Catalytic Reduction of NO by CO. Chemical Eng.& Processing: Process Intensification, 159, 108232.
• 10. Zhang, Y., Chu, Q., Shi, Y., Gao, J., Xiong, W., Huang, L., Ding, Y., 2021. Synthesis of Bimetallic Ag-Ni-MOF-74 Catalyst with Excellent CO-SCR Performance in Low Temperature Range. Acta Chimica Sinica, 79(3), 361-368.
• 11. Du X., Gao X., Fu Y., Gao F., Luo Z., Cen K. (2012). The Co-effect of Sb and Nb on the SCR Performance of the V2O5/TiO2 Catalyst. Journal of Colloid and Interface Science, 368, 406-412.
• 12. Liu, F., W. Shan, D. Pan, T. Li, and H. He. 2014. Selective Catalytic Reduction of NOx by NH3 for Heavy-duty Diesel Vehicles. Chinese Journal of Catalysis 35(9), 1438-45.
• 13. Zhao B., Ran R., Guo X., Cao L., Xu T., Chen Z., Wu X., Si Z., Weng D. (2017). Nb-Modified Mn/Ce/Ti Catalyst for the Selective Catalytic Reduction of NO with NH3 at Low Temperature. Applied Catalysis A: General, 545, 64-71.
• 14. Kang, W., Choi, B., Jung, S., Park, S., 2018. PM and NOx Reduction Characteristics of LNT/DPF +SCR/DPF Hybrid System. Energy 143 (January), 439-47.
• 15. Keskin, A., Yaşar, A., Candemir, O.C., Özarslan, H., 2020. Influence of Transition Metal Based SCR Catalyst on the NOx Emissions of Diesel Engine at Low Exhaust Gas Temperatures. Fuel, 273, 117785.
• 16. Keskin, Z., Özgür, T., Özarslan, H., Yakaryılmaz, A.C., 2021. Effects of Hydrogen Addition into Liquefied Petroleum Gas Reductant on the Activity of Ag-Ti-Cu/Cordierite Catalyst for Selective Catalytic Reduction System. International Journal of Hydrogen Energy, 46, 7634-7641.