On the soot combustion mechanism using 3DOM ceria catalysts

Alcalde‐Santiago, Virginia; Davó‐Quiñonero, Arantxa; Lozano‐Castelló, Dolores; Bueno‐López, Agustín

doi:10.1016/j.apcatb.2018.04.023

Cited by 92 publications

(50 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…NO 2 -assisted soot combustion over three dimensionally ordered macroporous (3DOM) ceria-based catalysts was studied in [ 83 ]. Both the use of the colloidal crystal template of monodisperse spheres of PMMA and the addition of copper via impregnation step contributed to the high efficiency of the catalyst.…”

Section: Ceria Preparation Methods Based On Artificial Templatesmentioning

confidence: 99%

Template Synthesis of Porous Ceria-Based Catalysts for Environmental Application

et al. 2020

View full text Add to dashboard Cite

Porous oxide materials are widely used in environmental catalysis owing to their outstanding properties such as high specific surface area, enhanced mass transport and diffusion, and accessibility of active sites. Oxides of metals with variable oxidation state such as ceria and double oxides based on ceria also provide high oxygen storage capacity which is important in a huge number of oxidation processes. The outstanding progress in the development of hierarchically organized porous oxide catalysts relates to the use of template synthetic methods. Single and mixed oxides with enhanced porous structure can serve both as supports for the catalysts of different nature and active components for catalytic oxidation of volatile organic compounds, soot particles and other environmentally dangerous components of exhaust gases, in hydrocarbons reforming, water gas shift reaction and photocatalytic transformations. This review highlights the recent progress in synthetic strategies using different types of templates (artificial and biological, hard and soft), including combined ones, in the preparation of single and mixed oxide catalysts based on ceria, and provides examples of their application in the main areas of environmental catalysis.

show abstract

Section: Ceria Preparation Methods Based On Artificial Templatesmentioning

confidence: 99%

Template Synthesis of Porous Ceria-Based Catalysts for Environmental Application

et al. 2020

View full text Add to dashboard Cite

show abstract

“…PMMA colloidal crystals were prepared following the methodology previously described elsewhere. [23,24] After synthesis, a cerium citrate ethanolic solution was infiltrated into the PMMA colloidal crystals. This cerium citrate solution (0.476 M) was obtained by dissolving cerium nitrate (Ce(NO 3 ) 3 · 6H 2 O) and citric acid in stoichiometric proportion in ethanol.…”

Section: Methodsmentioning

confidence: 99%

“…Considering the same concept, three-dimensionally ordered macroporous (3DOM) catalysts have demonstrated an improved activity in soot combustion in comparison to their disordered equivalent, which was associated to the enhanced soot-catalyst contact. [23][24][25] However, this porosity is not optimized to the soot morphology and only several contact points are still achieved. 3DOM structures are composed by spherical voids typically with 50-300 nm of diameter [26][27][28][29] whereas soot particles are formed by agglomerated spherical primary particles with an average primary particles diameter ranging from 10 to 25 nm and average aggregate sizes in the range of 50 to 300 nm.…”

Section: Introductionmentioning

confidence: 99%

Key‐lock Ceria Catalysts for the Control of Diesel Engine Soot Particulate Emissions

et al. 2020

View full text Add to dashboard Cite

A new concept, referred to as key‐lock catalyst, is presented in this article. Soot combustion ceria catalysts were prepared combining hard (polymethylmethacrylate colloidal crystals) and soft (Pluronic F127) templates, tuning the porosity of ceria in different size ranges to match the morphology of soot aggregates. The catalysts porosity was characterized in detail by N2 adsorption‐desorption isotherms and Hg‐porosimetry. XRD and H2‐TPR characterization ruled out that differences in activity are related neither with crystallographic nor with redox properties. As a proof of key‐lock catalyst concept, an optimum key‐lock ceria catalyst was synthesized by combining large macropores (100–300 nm) with mesopores (10–30 nm), because they fit to the large soot aggregates and to primary soot particles sizes, respectively. The best soot combustion activity of the optimum key‐lock catalyst is attributed to the optimum transfer of ceria active oxygen from catalyst to soot. The catalytic results confirmed that all ceria catalysts prepared with different porosity oxidize NO to NO2 at the same rate, and the NO2‐assisted soot combustion pathway is not affected by tuning ceria porosity. This double‐templated synthesis and the key‐lock concept opens a new synthesis approach to design noble‐metal free soot combustion catalysts based on the highly effective active oxygen mechanism.

show abstract

“…In the case of VOCs, and particularly in the case of the oxidation of the remaining hydrocarbons (HC), the following oxidic systems and compounds have been reported as being active: Co 3 O 4 , MnO 2 , CeO 2 , and CuO [21][22][23][24][25][26][27][28][29][30][31]. The combustion reaction of particulate matter has been extensively studied in recent decades, identifying catalysts with very diverse active phases [32][33][34][35][36][37][38][39][40][41]. A meticulous study of them can be found in a review by A. Bueno Lopez et al [32] and in a more recent review by D. Fino et al [33].…”

Section: Introductionmentioning

confidence: 99%

Zirconia-Supported Silver Nanoparticles for the Catalytic Combustion of Pollutants Originating from Mobile Sources

et al. 2019

View full text Add to dashboard Cite

This work presents the physicochemical characterization and activity of zirconia-supported silver catalysts for the oxidation of pollutants present in diesel engine exhaust (propane, propene, naphthalene and soot). A series of silver-supported catalysts AgxZ (x = 1, 5 and 10 wt.%, Z = zirconia) were prepared, which were studied by various characterization techniques. The results show that silver is mainly found under the form of small metal nanoparticles (<10 nm) dispersed over the support. The metallic phase coexists with the AgOx oxidic phases. Silver is introduced onto the zirconia, generating Ag–ZrO2 catalysts with high activity for the oxidation of propene and naphthalene. These catalysts also show some activity for soot combustion. Silver species can contribute with zirconia in the catalytic redox cycle, through a synergistic effect, providing sites that facilitate the migration and availability of oxygen, which is favored by the presence of structural defects. This is a novel application of the AgOx–Ag/ZrO2 system in the combustion reaction of propene and naphthalene. The results are highly promising, given that the T50 values found for both model molecules are quite low.

show abstract

On the soot combustion mechanism using 3DOM ceria catalysts

Cited by 92 publications

References 40 publications

Template Synthesis of Porous Ceria-Based Catalysts for Environmental Application

Template Synthesis of Porous Ceria-Based Catalysts for Environmental Application

Key‐lock Ceria Catalysts for the Control of Diesel Engine Soot Particulate Emissions

Zirconia-Supported Silver Nanoparticles for the Catalytic Combustion of Pollutants Originating from Mobile Sources

Contact Info

Product

Resources

About