Desarrollo y certificación ambiental de catalizadores para emisiones de escape de automóviles

Desde la década de 1980 un grupo de investigadores del Instituto de Investigaciones en Catálisis y Petroquímica “Ing. José Miguel Parera” venía estudiando en Santa Fe, Argentina la eliminación de contaminantes en gases de escape de motores de combustión interna. A partir de la firma de un convenio con YPF (Yacimientos Petrolíferos Fiscales) se llevó a cabo en 1991 el primer desarrollo nacional de un “Convertidor catalítico de oxidación (elimina CO y HC) de contaminantes de escape de motores ciclo Otto”, evaluado con éxito en los Laboratorios de YPF. Un convenio posterior con la Pyme Vega y Camji, ubicada en la Ciudad de Buenos Aires, permitió continuar con el desarrollo de un catalizador de “Tres Vías” para la eliminación de CO, HC y óxidos de nitrógeno (NOx). Como parte del proyecto la Pyme instaló un laboratorio con tecnología de inspección de emisiones de escape (g/km) de automóviles bajo una secuencia de manejo urbano de los Estados Unidos (USIM240), permitiendo evaluar con éxito la performance del catalizador desarrollado en UNL, frente a otros prototipos comerciales disponibles en el mercado internacional. El proyecto solo alcanzó la etapa de escalado productivo, quedando pendiente la instalación de la planta productora. El Laboratorio de Vega y Camji alcanzó en 1998 la certificación del Instituto Nacional de Tecnología Industrial, otorgándole el reconocimiento oficial del servicio. La tecnología y el know-how desarrollados, fueron transferidos en 1998 al estado argentino bajo convenio con la Secretaría de Ambiente y Desarrollo Sustentable (SAyDS), propiciando la construcción del Laboratorio de Control de Emisiones Gaseosas Vehiculares (LCEGV), que oficializó sus actividades en 1999 con servicios para la industria automotriz. Habiendo consolidado hoy sus servicios y contrastado sus mediciones con laboratorios de referencia europeos y del MERCOSUR, el LCEGV se ha convertido en uno de los más modernos y destacados laboratorios de Latinoamérica.Fil: Lombardo, Eduardo Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Camji, Daniel. Vega y Camji; ArgentinaFil: Vassallo, Julio. Laboratorio de Control de Emisiones Gaseosas Vehiculares; Argentin

Thermal analysis of K(x)/La2O3, active catalysts for the abatement of diesel exhaust contaminants

Potassium loaded lanthana is a promising catalyst to be used for the abatement of diesel exhaust pollutants. In this paper we have combined several thermal techniques to study relevant processes that take place during the soot combustion reaction. Temperature programmed oxidation (TPO) experiments show that with potassium loadings between 4.5 and 10 wt.% and calcination temperatures between 400 and 700 °C, these catalysts mixed with soot give maximum combustion rates between 350 and 400 °C. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicate that the reaction coexists with the thermal decomposition of bulk hydroxide species. For the La2O3 solid, the La(OH)3→LaO(OH) and LaO(OH)→La2O3 processes occur at ca. 360 and 500 °C, respectively, whereas the presence of K in the K(x)/La2O3 catalysts provokes a shift of these endothermic peaks to higher temperatures. In all the studied solids, oxycarbonates decompose in the 550–800 °C temperature range. On the other hand, microbalance results show that the bulk carbonate formation depends on both the potassium content and the calcination temperature. The High Frequency CO2 Pulses technique is useful to study the dynamics of the CO2 adsorption–desorption process and to characterize the surface basicity of the solids. When both La2O3 and K/La2O3 solids are calcined at 700 °C, a strong decrease on the CO2–surface interaction takes place, which correlates with a small decrease in catalytic activity and with an increase in the K/La surface ratio. These effects may be originated, at least in part, by a decrease in oxygen vacancies concentration and a thermal dehydroxylation of the catalysts.Fil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Querini, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Activity of Catalytic Ceramic Papers to Remove Soot Particles—A Study of Different Types of Soot

Diesel soot particles are of concern for both the environment and health. To catalytically remove them, it is important to know their structure and composition. There is little described in the literature on how catalysts favor the combustion of different soot fractions. In this work, programmed temperature oxidation (TPO) experiments were carried out using Co,Ce or Co,Ba,K catalysts supported on ceramic papers. Soot particles were obtained by burning diesel fuel in a vessel (LabSoot) or by filtering exhaust gases from a turbo diesel engine in a DPF filter (BenchSoot), and compared with a commercial diesel soot: Printex U. Various characterization techniques were useful to relate the characteristics of both the soot particles and the catalysts with the TPO results. The maximum catalytic soot burn rate (TM) temperatures were in the range of diesel exhaust temperatures that would facilitate in-situ regeneration of the DPF. The Co,Ba,K catalyst showed a higher catalytic effect in LabSoot, as the latter exhibited the largest primary particles and the higher order of graphene layers, for which the potassium-containing catalyst improves the contact between soot and catalyst and favors the combustion of soot, while the Co,Ce catalyst preferentially enhanced the combustion of commercial soot by supplying active oxygen.Fil: Leonardi, Sabrina Antonela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Spectroscopic characterization of Mn-Co-Ce mixed oxides, active catalysts for COPROX reaction

Mn-Co-Ce mixed oxides are active and selective catalysts for the CO preferential oxidation (COPROX), which is a promising process for the purification of hydrogen streams. In this work, we report a careful spectroscopic characterization of the said system, with the aim of relating its physical chemistry properties to the catalytic behavior. In all the Co-Mn-Ce samples, we detected the formation of partially developed (Mn,Co)3O4 mixed spinels. The presence of these species, which can be reduced during the TPR experiments at an intermediate temperature range (300-600°C), was also suggested by XRD and LRS. XPS results show that in all cases the catalytic surface is enriched in Mn, while the opposite occurs for Co. As regards the catalytic activity, we observed that the best formulations were those containing intermediate Mn/Co ratios (1/4 and 1/1), which can be ascribed to the promoting effect of Mn in improving the redox properties of Co active sites and provoking an increase in surface area. The best catalyst, which has a Mn/Co ratio of 1/4, was very stable after 75 h of time-on-stream with CO2 included in the feed.Fil: Gómez, Leticia Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET -Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina;Fil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET -Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina;Fil: Boix, Alicia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET -Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica; Argentina

The beneficial effect of silica on the activity and thermal stability of PtCoFerrierite-washcoated cordierite monoliths for the SCR of NOx with CH4

PtCoFerrierite washcoated on a ceramic monolith is an active and selective catalyst for the SCR of NOx with methane. For our system, we found that the addition of a binder to the slurry used for the washcoat is necessary to improve the adherence and to obtain a selective catalyst. In our case, we used 2 wt.% of Cabot Silica. Ultrasound experiments used to comparatively evaluate the coating adherence showed that silica prevents the washcoat loss due to attrition. Similar monolithic catalysts, but prepared without a binder, resulted in catalysts with poor activity for NOx reduction, but still active for the deep oxidation of methane with oxygen. Monoliths washcoated without a binder showed both Pt segregation to the outer surface of zeolite crystals and formation of the non-selective Co3O4. Segregated Pt clusters and cobalt oxide promote the methane combustion with oxygen, thus leaving the NOx molecules unreacted. Moreover, due to Pt segregation, the necessary intimate contact between Pt and Co active species is not favored in this catalyst, which also contributes to the low selectivity to N2.Fil: Boix, Alicia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Zamaro, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Lombardo, Eduardo Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Ceramic Fiber-Based Structures as Catalyst Supports: A Study on Mass and Heat Transport Behavior Applied to CO 2 Methanation

Fibrous structures present interesting characteristics as catalyst supports for heat- and mass-transfer-limited reactions. This paper investigates the mass and heat transport behavior of ceramic fiber-based catalysts (catalytic ceramic paper) by applying them to the exothermic reaction of CO2 methanation. Catalytic experiments were carried out to fit the activity of the catalysts with known kinetics. A fixed-bed reactor model was used to determine the efficiency and efficiency losses caused by different transport phenomena, as well as to perform a sensitivity study focused on heat transfer. The results show that heat transfer limitations are the main cause for losses in reactor efficiency, with steep temperature profiles developing inside the reactor. Poor heat transfer limits the development of highly active catalysts, while pressure drop restricts the flow rate and therefore the productivity. The use of ceramic materials with higher thermal conductivity and increasing the fiber diameter are promising approaches to enhance heat transfer, reduce pressure drop, and improve overall reactor performance.Fil: Sánchez, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Güttel, Robert. Universitat Ulm. Faculty Of Natural Sciences; Alemani

New Formulations of Ni-Containing Ceramic Papers to Enhance the Catalytic Performance for the Oxidative Dehydrogenation of Ethane

Ceramic papers composed of silica–alumina fibers structured using colloidal suspensions as binders constitute interesting materials to be used as flexible supports of catalytic materials. The deposition of Ni as the active ingredient together with Zr or Ce promoters resulted in active and selective structured catalysts for the oxidative dehydrogenation of ethane; these structured catalysts also exhibited acceptable mechanical properties. The employed binder agents (nanoparticles of ceria, zirconia, or yttria-stabilized zirconia) homogeneously covered the fiber surface, contributing to the dual function of building a three-dimensional arrangement and favoring the anchoring of the catalytic formulations. The prepared papers showed nickel oxide as the active phase. The incorporation of cerium or zirconium as promoters enhanced the catalytic properties. The former element mainly produced an increase in ethane conversion, whereas the latter markedly improved ethylene selectivity. In both cases, an ethylene productivity was obtained in the promoted systems which was higher than that in the unpromoted samples. It is likely that the formation of the solid solutions Ni–Ce–O and Ni–Zr–O, as suggested by X-ray diffraction and laser Raman spectroscopy analyses, plays an important role in these effects. The best catalyst was the one containing nickel as the active phase, Ce as the promoter, and ZrY as the binder agent, for which ethylene productivity at 400 °C was ca. 513 g ethylene/(kgcat h). The binder agent addition was necessary to join the fibers, thus improving the mechanical properties of the papers, but they also affected the catalytic performance through the coverage of ceramic fibers and the resulting interaction with the catalytic compounds. The performed tensile index tests showed that the colloidal suspension of ceria produced papers with mechanical properties better than those of zirconia or zirconia–yttria because they exhibited greater resistance and flexibility.Fil: Bortolozzi, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Banus, Ezequiel David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin

Ultrasound-Assisted Deposition of Co-CeO2 onto Ceramic Microfibers to Conform Catalytic Papers: Their Application in Engine Exhaust Treatment

The combination of the selective catalytic reduction technology with catalytic filters constitutes one of the most efficient ways for diesel engine exhaust treatment. In this paper, the development of catalytic ceramic papers as structured systems for the abatement of diesel soot particles is addressed. Ceramic papers were prepared by the dual-polyelectrolyte papermaking method, which is based on the conventional papermaking technique used for cellulosic papers, in which a portion of cellulosic fibers is replaced by ceramic ones. The deposition of Co and Ce as catalytic materials by the wet spray method on ceramic papers was studied for the development of structured catalysts using an ultrasonic nebulizer and different solvents. The use of alcohol-water solutions for the impregnation of cobalt generated smaller particles and a high dispersion of them on the ceramic fibers, greater than that obtained when pure water was employed. Temperature programmed oxidation (TPO) assays showed that the best catalytic performance was acquired with the catalysts generated with alcohol solvents, showing a maximum rate for soot combustion at a temperature close to 400 °C. The adequate soot combustion performance and the high thermal and catalytic stability make catalytic ceramic papers impregnated by the wet spray method, promising systems for their application as diesel particulate filters.Fil: Sacco, Nicolás Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Banus, Ezequiel David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Bortolozzi, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin

Simultaneous removal of soot and nitrogen oxides from diesel engine exhausts

In this paper, previously reported findings and new results presented here are discussed with the main objective of establishing the reaction mechanism for soot oxidation on different supports and catalysts formulations. Catalysts containing Co, K and/or Ba supported on MgO, La2O3 and CeO2 have been studied for diesel soot catalytic combustion. Among them, K/La2O3 and K/CeO2 showed the best activity and stability for the combustion of soot with oxygen. A reaction mechanism involving the redox sites and the surface-carbonate species takes place on these catalysts. On the other hand, Co,K/La2O3 and Co,K/CeO2 catalysts display activity for the simultaneous removal of soot and nitric oxide. The soot-catalyst contacting phenomenon was also addressed. A synergic La-K effect was observed in which the mechanical mixtures of soot with K-La2O3 showed higher combustion rates than those observed when K and La were directly deposited on the soot surface. The effect of the addition of Ba was explored with the aim of promoting the interaction of the solid with NO2, thus combining the NOx catalytic trap concept with the soot combustion for filter regeneration. Ba/CeO2 and Ba,K/CeO2 were effective in NOx absorption as shown in the microbalance experiments. However, the formation of stable nitrate species inhibits the soot combustion reaction. © 2002 Elsevier Science B.V. All rights reserved.Fil: Pisarello Milesi, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Peralta, María Ariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Querini, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin

Synthesis and characterization of ZSM-5 coatings onto cordierite honeycomb supports

Zeolite ZSM-5 layers (up to ca. 30% by weight) have been synthesized on cordierite substrates, following either a direct hydrothermal synthesis procedure or a secondary growth method, in this case after seeding of the support. The Si/Al ratio in the synthesis gel ranged from 14 to 100, but layers with a high Al content (i.e. a low Si/Al ratio) could not be prepared directly on the cordierite support. However, MFI layers with a low Si/Al ratio were readily grown after depositing an intermediate Si-rich layer. The results also show that the Si/Al ratio of the synthesis gel has a direct effect on the morphology, crystallinity and orientation of the MFI layer formed.Fil: Ulla, Maria Alicia del H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Mallada, R.. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Coronas, J.. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Gutierrez, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Miro, Eduardo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Santamaría, J.. Universidad de Zaragoza. Facultad de Ciencias; Españ