Construction of LaFe1−xMnxO3/attapulgite nanocomposite for photo-SCR of NOx at low temperature

Abstract

LaFe 1-x Mn x O 3 /attapulgite (ATP) nanocomposite was prepared by a sol-gel method. The structures and physicochemical properties were investigated by X-ray diffraction (XRD), Transmission electron microscope (TEM), UV-visible diffused reflectance spectroscopy (UV-vis) and X-ray photoelectron spectroscopy (XPS). LaFe 1-x Mn x O 3 /ATP nanocomposite was used as catalyst for photo-assisted selective catalytic reduction (photo-SCR) of NO under visible light irradiation. The impact of the various Mn doping fraction on the NO conversion was investigated. Results indicate that LaFe 1-x Mn x O 3 remains as a perovskite solid solution supported uniformly on the ATP surface when x is less than 0.4. When x is beyond 0.4, LaMnO 3 phase coprecipitates with the perovskite LaFe 0.6 Mn 0.4 O 3 and forms coherent heterojunction of LaMnO 3 /LaFe 0.6 Mn 0.4 O 3 on ATP. The photocatalytic deNO x activity of the composite material is the highest when x = 0.6 and the NO conversion reaches as high as 85% even under room temperature.

Magnetic γ-Fe2O3-Loaded Attapulgite Sorbent for Hg0 Removal in Coal-Fired Flue Gas

“…In addition, the surface of ATT can be used as a nucleation center to stabilize nanoparticles, leading to the formation of a uniform metal compound /ATT nano-composite 32,33 . There are increasing research efforts focusing on the modification of ATT as a catalyst for the selective catalytic reduction (SCR) of NOx in recent years [33][34][35] . However, few have investigated Hg 0 removal from coal-fired boiler flue gases by using ATT.…”

Semicondutores Heteroestruturados: Uma Abordagem Sobre Os Principais Desafios Para a Obtenção E Aplicação Em Processos Fotoquímicos Ambientais E Energéticos

“…Entretanto, o sucesso desses processos está ainda associado a um elevado custo energético, uma vez que se faz necessário o uso de temperaturas elevadas para que as reações ocorram com conversões satisfatórias. 127 Diante desse problema, diversos grupos de pesquisa têm proposto o abatimento fotocatalítico de tais compostos como um processo alternativo e promissor devido principalmente ao seu menor custo operacional, uma vez que se pode utilizar a luz solar como fonte de energia, e à sua alta eficiência. O abatimento fotocatalítico de NO x pode seguir um mecanismo de…”

“…Embora a fotorredução de NO x a N 2 seja uma tecnologia muito interessante e promissora, principalmente quando se utiliza outros poluentes gasosos associados ao processo como agentes redutores, como o CO, hidrocarbonetos (e.g., CH 4 ) ou NH 3 , a maioria dos estudos sobre abatimento fotocatalítico de NO x utilizando fotocatalisadores heteroestruturados encontrados na literatura refere-se à conversão de NO em NO 3 ou HNO 3. 127,129,130 O mecanismo da foto-oxidação de NO x pode ser descrito conforme as equações a seguir. 130,131…”

Synthesis, Property Characterization and Photocatalytic Activity of the Ag3PO4/Gd2BiTaO7 Heterojunction Catalyst under Visible Light Irradiation

“…The Z-scheme heterojunction greatly improved the redox property and electron transport rate of the catalyst by generating effective electron-hole recombination within the two semiconductors [52]. Li et al [53][54][55][56] discovered and prepared a series of doped perovskite catalysts with excellent low-temperature redox properties, such as direct Zscheme LaFe 1−x Mn x O 3 /ATP and indirect Z-scheme LaCoO 3 /RGO/ATP. Subsequently, these catalysts were applied to photo-SCR, light nitrogen and other fields, and as a result, these catalysts showed excellent activity.…”