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

Yıl 2024, , 339 - 347, 11.07.2024

Himmet Özarslan

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

Öz

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.

Anahtar Kelimeler

Selective catalytic Reduction, Catalyst, Cordierite, NOx emission

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

Öz

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.

Anahtar Kelimeler

Seçici katalitik indirgeme, Katalizör, Kordiyerit, NOx emisyonu

Kaynakça

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