5 research outputs found
Effect of the support in Pt and PtSn catalysts used for selective hydrogenation of carvone
In this paper, a study on the hydrogenation of carvone by using Pt/Al2O3, PtSn/Al2O3, PtGe/Al2O3, Pt/C and PtSn/C is reported. TPR, H2 chemisorption, XPS and test reaction results show that the addition of a second metal to Pt leads to important modifications of the structure of the metallic phase, though these modifications are different according to the nature of the support (Al2O3 or C). The activity and selectivity of these catalysts in carvone hydrogenation depend not only on the composition of the metallic phase, but also on the nature of the support. Thus, adding Sn or Ge to Pt/Al2O3 enhances the selectivity to unsaturated ketones (at a fixed carvone conversion, Xcarv = 1). When Pt is supported on activated carbon, small amounts of unsaturated alcohols are observed. The Sn addition to Pt/C sharply enhances the selectivity to carveol formation (the doubly unsaturated alcohol) reaching values close to 100% at the initial stages of the reaction. © 2001 Elsevier Science B.V.Fil: de Miguel, Sergio Ruben. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Román Martinez, M.C.. Universidad de Alicante; EspañaFil: Cazorla AmorĂłs, Diego. Universidad de Alicante; EspañaFil: Jablonski, Estanislao Lorenzo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Scelza, Osvaldo Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; Argentin
Preparation of Pt catalysts supported on activated carbon felts (ACF)
Activated carbon felts (ACFs) have been used as supports for Pt catalysts. The preparation was carried out by the impregnation method using chloroplatinic acid as metal precursor. The effect of impregnation time and surface chemistry of the support on the catalytic properties and the characteristics of the metallic phase have been investigated. Nitrobenzene (Nbz) hydrogenation in liquid phase at 25 °C and cyclohexane (CH) dehydrogenation in gas phase at 300 °C were used as catalytic tests. The state of platinum in reduced catalysts (at 100 and 350 °C) was studied by TPR and XPS. Oxygen surface groups only produce a slight effect on the catalytic properties. The use of low impregnation times (30 min) during the preparation of Pt/ACF leads to catalysts with Pt mainly deposited in the outer shell of the fibers, while at higher impregnation times, the metallic atoms seem to be deposited inside the pores. Pt(0) species appear in catalysts reduced at 100 °C by effect of the reducing properties of the carbon fiber exhibiting a considerable catalytic activity for Nbz hydrogenation.Fil: de Miguel, Sergio Ruben. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Vilella, Irene MarĂa Julieta. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Jablonski, Estanislao Lorenzo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Scelza, Osvaldo Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Salinas Martinez de Lecea, C.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Linares Solano, A.. Universidad de Alicante; Españ
Estudio de Catalizadores de Rutenio para la obtenciĂłn de Gas de SĂntesis a partir del Reformado Seco de Metano
This work studies the catalytic performance in dry reforming of Ru catalysts supported on Îł-Al2O3 promoted with Na, K, Mg, Ca and Ba. The supports and the catalysts were characterized and tested in the reaction of CH4 reforming with CO2. Ru/Al2O3-Na and Ru/Al2O3-K catalysts showed higher conversions and better H2/CO molar ratios. This catalytic behavior would be related with the higher
metallic dispersions and with the basicity of the support. When the reduction time in H2 was shortened, a decrease of the conversions for all the catalysts, except for Ru/Al2O3-Na, was observed. This phenomenon would not be due to the thermal effect but to the reduction time.Fil: Maina, Silvia Carolina Palmira. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: de Miguel, Sergio Ruben. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Scelza, Osvaldo Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; ArgentinaFil: Jablonski, Estanislao Lorenzo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica ; Argentin
Reforming of CH4 with CO2 on Pt-supported catalysts: Effect of the support on the catalytic behaviour
This paper reports a study about the behaviour of different Pt-based catalysts supported on Al2O3, Na-Al2O 3, K-Al2O3 and ZrO2 in methane reforming with CO2. Results indicate that Pt/Na (0.3 wt%)-Al 2O3 and Pt/ZrO2 catalysts show both a good activity and selectivity with a very high catalytic stability at 1073 K. The Pt/K (0.3 wt%)-Al2O3 catalyst showed a good performance but a slightly lower conversion level than Pt/Na (0.3 wt%)-Al2O 3. On the other hand, the Pt/Al2O3 catalyst displayed an important decrease of the methane conversion through the reaction time at 1073 K and hence, a lower catalytic stability due mainly to the carbon deposition. It can be concluded that either Na or K addition to Pt/Al 2O3 enhances the catalytic stability since they provide basic sites, which favour the dissociation reaction of CO2 into CO and O. The O species can react with the carbon deposited on the Pt, thus cleaning the metallic phase of the doped catalysts.Fil: Ballarini, Adriana Daniela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: de Miguel, Sergio Ruben. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Jablonski, Estanislao Lorenzo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Scelza, Osvaldo Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Castro, Alberto Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; Argentin
Citral condensation with acetone on Na-MgO and Li-MgO catalysts
The effect of the Na and Li addition to MgO on the pseudo-ionone production from citral and acetone condensation in liquid phase is reported. The Na addition improves the yield to pseudo-ionone (defined as mol of produced pseudo-ionone/mol of converted citral), reaching a value of 100%, while the Li addition has a poor effect. These results can be related to the different distribution of basic sites. It was found that the catalytic activity depends on the acetone/citral and the catalyst/citral ratios. Besides, a poisoning effect of the reaction products on the catalysts was observed, even though the activity of the used catalysts can be partially restored by extraction treatments.Fil: Jablonski, Estanislao Lorenzo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Vilella, Irene MarĂa Julieta. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Maina, Silvia Carolina Palmira. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: de Miguel, Sergio Ruben. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; ArgentinaFil: Scelza, Osvaldo Antonio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y PetroquĂmica "Ing. JosĂ© Miguel Parera"; Argentin