Desarrollo, Producción e Innovación en la Investigación científica
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Item Inhibition by nitrogen compounds in the simultaneous hydrogenation of polyaromatic compounds over Pt-Pd-F/AI203 catalyst.(Univesidsad Tecnológica Nacional., 2015) Balangero , Gerardo Simón; Falcón, Horacio; Beltramone, Andrea RaquelThe inhibiting effect of basic and non-basic nitrogen compounds on the hydrogenation of polyaromatic compounds and on the hydrodesulphurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6DMDBT), has been investigated on Pt-Pd-F/Al2O3 and compared with a commercial NiMo hydrotreating catalyst. Langmuir-Hinshelwood type rate equations were used to describe the reaction kinetics accurately with physically meaningful and well identified parameter values. Model parameters were tuned by fitting experimental data obtained in a continuous flow reactor at 345°C, 1000 psi pressure and different contact times. Pt-Pd-F/Al2O3 was more active than NiMo catalyst and conversion remained constant during 24 h of TOS. The model was able to correctly interpret all the experimental data. Parameter estimation results showed that phenanthrene and naphthalene inhibited the tetralin hydrogenation rate, whereas naphthalene and tetralin had no appreciable effect on the rate of phenanthrene conversion. This inhibition could be explained by the competitive adsorption and was described in the kinetic model by adsorption terms obtained from the multicomponent experiments. The inhibiting effect of different nitrogen compounds on the polyaromatic hydrogenation was determined. The following nitrogen compounds were investigated in this study: quinoline, 1,2,3,4-tetrahydroquinoline, indole, and indoline. The degree of inhibition was expressed in terms of an apparent adsorption constant derived from the kinetics.The inhibiting effect on the HDS of DBT and 4,6 DBT followed the same trend.Item Synthesis, characterization and catalytic performance of bimetallic Ir-Pt catalysts for tetralin hydrogenation.(Univesidsad Tecnológica Nacional, 2024) Anunziata , Oscar Alfredo; Beltramone, Andrea RaquelBimetallic Pt–Pd catalysts have received considerable attention, because they show high activity in a variety of catalytic applications (1) and stability compared with monometallic Pt or Pd catalysts. For instance, the bimetallic Pt–Pd catalysts have been shown to have higher resistance toward poisonscompared to Pt catalysts (2-4). For supported bimetallic clusters, the surface and bulk composition strongly depend on a series of parameters, for example, preparation procedures, metal–metal and metal–support interactions. The final goal is to find the optimal proportion of each metal in order to be more active in these processes.In this case a series of Ir and Pt modified SBA-15 were prepared by the consecutive wet impregnation method, with different content of each metal. The final catalysts were characterized by XRD, TEM and H2 chemisorption to study the effect of content of metal on the dispersion of iridium/platinum. The catalysts synthesized with similar percentage of both metal showed the best activity measured in tetralin hydrogenation. Platinum (Pt) and Iridium (Ir) nanoparticles were incorporated into SBA-15 support [1-4] by the wet co-impregnation method. The metal precursors were Iridium acetylacetonate and cloroplatinic acid. The samples were calcined at 500°C and previous to the catalytic test the samples were reduced by heating at 2°C/min to 450°C in a H2 stream for 5 h. Hereinafter this catalyst will be referred as Ir-Pt- SBA-15 (x), with x= 1-3. The catalytic activity was measured in a 4563Parr reactor, at 250°C, 15 atm of pressure of hydrogen and 360 rpm for tetralin hydrogenation (feed consisted in 50 mL of 5% v/v of tetralin (98.5% FLUKA) in Dodecane). The Pt-Ir-SBA-15 catalyst with 1 %wt. of each metals had the highest activity measured in tetralin hydrogenation at mild conditions. The good activity was correlated with higher Ir/Pt dispersion on SBA-15 mesostructured material used as support, as we seen by TEM and H2 Chemisorption, with higher active metal sites exposed to reactant. The Ir-Pt-SBA-15 activity is sufficiently high to envisage use in the final stages of a refinery process producing diesel fuel of high Cetane Number by hydrodearomatization.Item Hydrogenation of tetralin over Ir catalysts supported on titania-modified SBA-16(2014) Ledesma, Brenda; Vallés, Verónica; Rivoira, Lorena Paola; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelAbstract A series of Ti modified SBA-16 supports and their respective Ir-catalysts were prepared and character- ized to study the effect of support preparation method on the dispersion of iridium and on the characteristics of Ir surface species. Two methods of incorporation of titania were tested: the sol–gel method in order to obtain Ti as heteroatom and incipient wetness impregnation to obtain Ti as TiO2 (anatase phase). The results show that supports with different Ti species and dispersion can be obtained. The final catalyst was characterized at different preparation stages by XRD, elemental analysis and BET. The presence of Ti as Ti4? in the nanostructure of SBA and as TiO2 (anatase phase) was analyzed by UV–Vis–DRS and Raman spectroscopy. The iridium oxidation sate upon Ti-con- taining SBA-16 was studied by XPS, EDX, TEM and XRD, arriving at the good proportion of Ir0. H2 chemi- sorption and TEM characterization for Ti-SBA-16 indi- cated that Ir particle size was lower than anatase/SBA-16. The catalyst that we synthesized had good activity mea- sured in tetralin hydrogenation in presence of quinoline at mild conditions. The experimental data were quantitatively represented by a modified Langmuir–Hinshelwood-type rate equation. The preliminary results show these materials as promising catalysts for HDS/HDN reactions.Item Inhibition of the hydrogenation of tetralin by nitrogen and sulfur compounds over Ir/SBA-16(2011) Balangero, Gerardo Simón; Martínez, María Laura; Gómez Costa, Marcos Bruno; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelIn this work we study the catalytic properties of 5 wt.% Ir-containing SBA-16 catalysts (with and without aluminum as heteroatom), in the hydrogenation of tetralin to decalin, in the presence of 100 ppm of N as quinoline, indole and carbazole, and 100 ppm of S as dibenzothiophene and 4,6-dimethyl- dibenzothiophene at 250 ◦C and 15 atm of pressure of hydrogen, using a Parr reactor. Ir/SBA-16 and Ir/Al-SBA-16 were prepared by wetness impregnation using Iridium Acetylacetonate as source of Ir. The Ir/SBA-16 catalyst synthesized by us had high activity measured in tetralin hydrogenation at mild con- ditions. The experimental data was quantitatively represented by a modified Langmuir–Hinshelwood type rate equation, using the apparent adsorption constants calculated from the inhibition results for the individual compounds. The catalyst showed a good resistance to sulfur and nitrogen compounds. The inhibiting effect increased in the order: DBT < quinoline < 4,6-dimethyl-DBT < indole < carbazole. The inhibiting effect of the nitrogen/sulfur compounds was strong, but the activity was still higher than with commercial NiMo/alumina catalyst. We present in this contribution a successfully developed, high loaded and well dispersed Ir/SBA-16 catalysts, that have been shown to maintain a useful catalytic activity, even in the presence of relatively high amounts of sulfur compounds (up to 100 ppm, sulfur basis). Consequently, economically successful processes have evolved, based on this class of catalysts.Item Synthesis, characterization and catalytic performance of bimetallic Ir-Pt catalysts for tetralin hydrogenation(2014) Vallés, Verónica; Ledesma, Brenda; Rivoira, Lorena Paola; Cussa, Jorgelina; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelBimetallic Pt–Pd catalysts have received considerable attention, because they show high activity in a variety of catalytic applications (1) and stability compared with monometallic Pt or Pd catalysts. For instance, the bimetallic Pt–Pd catalysts have been shown to have higher resistance toward poisonscompared to Pt catalysts (2-4). For supported bimetallic clusters, the surface and bulk composition strongly depend on a series of parameters, for example, preparation procedures, metal–metal and metal–support interactions. The final goal is to find the optimal proportion of each metal in order to be more active in these processes.In this case a series of Ir and Pt modified SBA-15 were prepared by the consecutive wet impregnation method, with different content of each metal. The final catalysts were characterized by XRD, TEM and H2 chemisorption to study the effect of content of metal on the dispersion of iridium/platinum. The catalysts synthesized with similar percentage of both metal showed the best activity measured in tetralin hydrogenation. Platinum (Pt) and Iridium (Ir) nanoparticles were incorporated into SBA-15 support [1-4] by the wet co-impregnation method. The metal precursors were Iridium acetylacetonate and cloroplatinic acid. The samples were calcined at 500°C and previous to the catalytic test the samples were reduced by heating at 2°C/min to 450°C in a H2 stream for 5 h. Hereinafter this catalyst will be referred as Ir-Pt- SBA-15 (x), with x= 1-3. The catalytic activity was measured in a 4563Parr reactor, at 250°C, 15 atm of pressure of hydrogen and 360 rpm for tetralin hydrogenation (feed consisted in 50 mL of 5% v/v of tetralin (98.5% FLUKA) in Dodecane). The Pt-Ir-SBA-15 catalyst with 1 %wt. of each metals had the highest activity measured in tetralin hydrogenation at mild conditions. The good activity was correlated with higher Ir/Pt dispersion on SBA-15 mesostructured material used as support, as we seen by TEM and H2 Chemisorption, with higher active metal sites exposed to reactant. The Ir-Pt-SBA-15 activity is sufficiently high to envisage use in the final stages of a refinery process producing diesel fuel of high Cetane Number by hydrodearomatization.Item Syntesis, characterization and hydrotreating catalitic performance of Ir/Ti-SBA-16 and Ir/TIO2-SBA-16.(2014) Ledesma, Brenda; Vallés, Verónica; Rivoira, Lorena Paola; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelA series of Ti modified SBA-16 supports and their respective Ir-catalysts were prepared, and characterized to study the effect of support preparation method on the dispersion of iridium and on the characteristics of Ir surface species, with the main aim of obtaining Nitrogen-tolerant catalysts to be used in second stage processes of mild-hydrotreating. Two methods of titania incorporation were tested: the sol-gel method in order to obtain Ti as heteroatom and incipient wetness impregnation to obtain Ti as TiO2 (anatase phase). The final catalyst was characterized at different stage of preparation by XRD, EDX, TEM, elemental analysis and BET, arriving at the good proportion of Ir0. The presence of Ti as Ti+4 in the nanostructure of SBA and as TiO2 (anatase phase) was analyzed by UV-vis-DRS and Raman spectroscopy. The average metal particle size indicates that the Ir particle size is lower when we used Ti-SBA-16 than anatase/SBA-16. We study the catalytic properties of 1 wt% Ir-containing SBA-16 materials modified with Ti as heteroatom and impregnated with TiO2 (anatase phase), in the hydrogenation of tetralin to decalin in the presence of 100 ppm of N as quinoline at 250°C and 15 atm of pressure of hydrogen, using a Parr reactor. The catalysts synthesized by us had good activity measured in tetralin hydrogenation under mild conditions. The experimental data was quantitatively represented by a modified Langmuir-Hinshelwood type rate equation. The preliminary results show these materials as promising catalysts for HDT and HDN reactions.Item Tetralin hydrogenation and ring opening of decalin over Ir-Pt-SBA-15(2014) Vallés, Verónica; Rivoira, Lorena Paola; Ledesma, Brenda; Cussa, Jorgelina; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelA series of Ir and Pt modified SBA-15 were prepared by the consecutive wet impregnation method, with different content of each metal. The final catalysts were characterized by XRD, TEM and H2 chemisorption to study the effect of content of metal on the dispersion of iridium/platinum. The catalysts synthesized with similar percentage of both metals showed the best activity measured in tetralin hydrogenation and ring opening of decalin at mild conditions.Item Synthesis, characterization and hydrotreating activity of Ir catalysts supported on titania-modified mesoporous material(2014) Ledesma, Brenda; Vallés, Verónica; Rivoira, Lorena Paola; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelA titanium modified catalyst based on noble metal has been prepared with the main aim of obtaining Nitrogen-tolerant catalysts to be used in second stage processes of mild-hydrotreating. We study the catalytic properties of 1 wt% Ir-containing SBA-16 materials modified with Ti as heteroatom and impregnated with TiO2 (anatase phase), in the hydrogenation of tetralin to decalin in the presence of 100 ppm of N as quinoline at 250°C and 15 atm of pressure of hydrogen, using a Parr reactor. The iridium oxidation sate upon Ti-containing SBA-16 was studied by XPS, EDX, TEM and XRD, arriving at the good proportion of Ir0. The average metal particle size indicate that the Ir particle size is lower when we used Ti-SBA-16 than anatase/SBA-16. The experimental data was quantitatively represented by a modified Langmuir-Hinshelwood type rate equation. The preliminary results show these materials as promising catalysts for HDS/HDN reactions.