UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item Synthesis, characterization and hydrogen storage application of an activated carbon derivated from orange peels waste(2022) Juárez, Juliana María; Ledesma, Brenda Cecilia; Anunziata, Oscar Alfredo; Gómez Costa, Marcos Bruno; Beltramone, Andrea RaquelThe recovery and reuse of orange peel waste (OP) is a sustainable strategy in a circular economy. In this research, OP was used as the raw material for the preparation of a novel carbonaceous nanomaterial to be used in the adsorption of hydrogen as an alternative in the use of green hydrogen. Activated carbons were synthesized from orange peel using different synthesis conditions. The activation of the carbon was carried out by means of a chemical process with phosphoric acid as activating agent, varying the the activating agent/precursor ratio, and the contact time between them. The activating agent used is a solution of phosphoric acid (50 wt %) in different weight ratios of acid/precursor of 3:1 or 6:1, with resting time of 24 hours. The best support was obtained using a carbonization time of 1 h, a carbonization temperature of 470 , 6:1 precursor/acid ratio and 24 hours of resting time. According XRD analysis all samples present amorphous structure of activated carbons with BET surface areas of 1000 to 1400 m /g. With the activated carbons obtained with the best structure and texture, the adsorption of hydrogen and the effects on their meso / microporosity were studied. Said material significantly improved H storage behaviour compared to CMK-3 type nanostructured carbon (3.1% by weight at -196,15 C and 10 bar). The synthesized material shows promise in absorbing hydrogen by weak binding forces (physisorption).Item Nanoscopic hydrogen reservoir orange peel biowaste(2022) Juárez, Juliana María; Ledesma, Brenda Cecilia; Anunziata, Oscar A.; Gómez Costa, Marcos Bruno; Beltramone, Andrea RaquelThis work addresses the bio-waste valorization approach for the development of a novel carbonaceous nanomaterial to be used in the adsorption of hydrogen as an alternative in the use of green hydrogen. In this research, activated carbons were synthesized orange peel using different synthesis conditions. With the activated carbons obtained with the best structure and texture, the adsorption of hydrogen and the effects on their meso / microporosity were studied. The activation of the carbon was carried out by means of a chemical process with phosphoric acid as activating agent, varying the acid concentration, the substrate / activating agent ratio, and the contact time between them. The best support was obtained using a carbonization time of 1 h, a carbonization temperature of 470oC, a phosphoric acid concentration of 50% by weight and a BET area of ??1402 m2 / g. Said material significantly improved H2 storage behaviour compared to CMK-3 type nanostructured carbon (3.1% by weight at -196,15 oC and 10 bar). The synthesized material shows promise in absorbing hydrogen by weak binding forces (physisorption).Item Indole HDN using iridium nanoparticles supported on titanium nanotubes(2022) Ledesma, Brenda Cecilia; Martínez, María Laura; Gómez Costa, Marcos Bruno; Beltramone, Andrea RaquelThe HDN of indole was studied over iridium modified titanate nanotube catalyst. Titanium nanotube was prepared by the alkaline hydrothermal method. Iridium was added by wetness impregnation. The activity was compared with Ir–TiO2 and commercial NiMo/Al2O3 catalysts. The catalysts prepared were characterized by X-ray diffraction (XRD), N2 adsorption isotherms, UV–Vis-DRS, FTIR, XPS, TEM, Py-FTIR and H2-Chemisorption. XRD, N2 isotherms and UV–vis-DRS con- firmed the nanotube structure. The analysis showed that the mesoporous structure was maintained after Ir incorporation. The results showed that titanate nanotube as support significantly reduce the size of iridium crystallites and improves its dispersion considerably. Iridium titanate nanotube presented abundant and strong Brönsted acidity compared with TiO2 iridium catalyst. According a kinetic study, Ir–TNT was the most active catalyst for indole HDN, in mild conditions in a Batch reactor. The Brönsted acidity in synergic effect with Lewis acidity and hydrogenolysis capacity of iridium species were the responsible for the good activity.Item Iridium-supported SBA-15 modified with Ga and Al as a highly active catalyst in the hydrodenitrogenation of quinoline(2020) Ledesma, Brenda Cecilia; Martínez, María Laura; Beltramone, Andrea RaquelIr-supported SBA-15 was studied in the hydrodenitrogenation (HDN) of quinoline as a model nitrogen com- pound. The activity was improved when Si-SBA-15 support was modified with Ga and Al. Characterization of the catalysts was performed by XRD, N2 adsorption, XPS, H2 chemisorption, TEM, TPR, NMR and Py-FTIR. Dispersion and nature of the iridium species are dependent parameters on the support characteristics. Better activity for the elimination of the nitrogen atom was observed with Ir-Ga-SBA-15 as compared to Ir-Al-SBA-15 at 250 and 300 °C. However, the TON value for Ir-Al-SBA-15 was higher than Ir-Ga-SBA-15 at 300 °C, indicating the influence of the stronger Bronsted acidity in the elimination of the nitrogen atom at higher temperature. The enhanced activity was attributed to the particularly good dispersion of the iridium catalytic centers and to the synergic effect of Bronsted and Lewis acid sites, derived from Ga or Al incorporation. Ga-SBA-15 with 1 wt.% of iridium loading was the most active catalyst for HDN of quinoline. 95% of nitrogen elimination was attained at short time in mild conditions. The reusability of the catalyst presents it as potential catalyst for HDN process.Item Short time synthesis of titania modified-CMK-3 carbon mesostructure as support for Ir-catalyst applied in catalytic hydrotreating(2020) Ledesma, Brenda Cecilia; Juárez, Juliana María; Beltramone, Andrea RaquelTi-CMK-3 carbon mesoporous was prepared using a novel synthesis method. This new method avoids the hard template synthesis used commonly. The method developed here, allows to reduce time, energy consumptionand cost. Structural and textural characterization of the titanium modified-mesoporous carbonwas performed by N2 adsorption, XRD, UV–vis-DRS, Raman spectroscopy and TEM. The characterization results indicated that the textural and structural properties of the material synthesized by the short time method are comparable with the properties of the material prepared by the hard template method. Ti modi fied-mesoporous carbon was used as support of the iridium nanoparticles, in order to prepare a catalyst to be tested in model hydrotreating reactions. The catalyst obtained by wet impregnation with iridium acetylacetonate were characterized by ICP -AES, H2 chemisorption, TEM, XPS and FTIR of adsorbed pyridine. The high Ir dispersion and small particle size, along with the moderate Lewis acidity generated by the presence of titanium in the support, were responsible for the good performance and stability of the catalyst in the hydrogenation of tetralin in presence of nitrogen com - pounds. Main advantage of the present study is the reduction of time and cost in the synthesis of the new material and the applicability for HDT reactions.Item Influence of ti incorporation to bimetallic mesoporous carbon in the production of 2,5‑dimethylfuran from biomass derivatives(2021) Ledesma, Brenda Cecilia; Juárez, Juliana María; Domine, Marcelo E.; Beltramone, Andrea RaquelMonometallic and bimetallic supported catalysts were developed to produce 2,5-dimethylfuran (DMF) trough hydrogenolysis of 5-(hydroxymethyl)furfural (HMF). Detailed physicochemical characterization was done to understand structure–activity correlation. Through a series of experiments and comparatives tests, the synergistic effect among Pt, Ir, and Ti incorporated in the support was investigated. Results revealed that using the titanium contained ordered mesoporous carbon, synthesized by a novel technique, high selectivity to DMF was achieved. In the case of the best catalyst PtIr-TiC, the good activity and excellent selectivity to the desired product DMF (98% yield) was related to the high hydrogenating capacity of the bimetal- lic sites, the acid support characteristics and the high metal nanoparticles dispersion achieved on the mesoporous titanium modified carbon support.Item Hydrodenitrogenation of indol using iridium catalyst supported on titanium nanotubes(2022) Ledesma, Brenda Cecilia; Martínez, María Laura; Gómez Costa, Marcos Bruno; Beltramone, Andrea RaquelThe HDN of indole was studied over iridium modified titanate nanotube catalyst. Titaniun nanotube was prepared by the alkaline hydrothermal method. Iridium was added by wetness impregnation. The activity was compared with Ir-TiO2 and commercial NiMo/Al2O3 catalysts. The catalysts prepared were characterized by X-ray diffraction (XRD), N2 adsorption isotherms, UV–Vis-DRS, XPS, TEM, Py- FTIR and H2-Chemisorption. XRD, N2 isotherms and UV–vis-DRS confirmed the nanotube structure. The analysis showed that the mesoporous structure was maintained after Ir incorporation. The results showed that titanate nanotube as support significantly reduce the size of iridium crystallites and improves its dispersion considerably. Iridium titanate nanotube presented abundant and strong Bronsted acidity compared with TiO2 iridium catalyst. Ir-TNT was the most active catalyst for indole HDN, in mild conditions in a Batch reactor. The Bronsted acidity in synergic effect with Lewis acidity and hydrogenolysis capacity of iridium species were the responsible for the good activity.The HDN of indole was studied over iridium modified titanate nanotube catalyst. Titaniun nanotube was prepared by the alkaline hydrothermal method. Iridium was added by wetness impregnation. The activity was compared with Ir-TiO2 and commercial NiMo/Al2O3 catalysts. The catalysts prepared were characterized by X-ray diffraction (XRD), N2 adsorption isotherms, UV–Vis-DRS, XPS, TEM, Py- FTIR and H2-Chemisorption. XRD, N2 isotherms and UV–vis-DRS confirmed the nanotube structure. The analysis showed that the mesoporous structure was maintained after Ir incorporation. The results showed that titanate nanotube as support significantly reduce the size of iridium crystallites and improves its dispersion considerably. Iridium titanate nanotube presented abundant and strong Bronsted acidity compared with TiO2 iridium catalyst. Ir-TNT was the most active catalyst for indole HDN, in mild conditions in a Batch reactor. The Bronsted acidity in synergic effect with Lewis acidity and hydrogenolysis capacity of iridium species were the responsible for the good activity.Item Activated carbons synthetized from orange peel to produce clean energy(2022) Rivoira, Lorena Paola; Gómez Costa, Marcos Bruno; Ledesma, Brenda Cecilia; Beltramone, Andrea RaquelAs we all know, a clean energy revolution is taking place all over the world in pursuit of replacing oil. The present work stands out an environmental point of view by proposing biomass wastes from different industrial areas to produce not only a biofuel but also as raw material to synthetize the catalyst involved in the HDO reaction. In this way the process ceases to rely on the antiquated and obsolete linear economy where products, services, wastes, materials, water and energy have a beginning and an end to become a process with greater tendency to the modern circular economy, closely related to the idea of sustainability. Products, materials and resources are expected to last as long as possible while minimizing waste as much as possible too. Agricultural and forestry waste are available everywhere being a low cost raw material and it is possible to provide added value to the organic wastes of small and medium size enterprises. The hydrodeoxygenation (HDO) of guaiacol has been performed in a batch reactor under 12 atm of H2 and different temperatures over activated carbon synthetized from orange peel discarded from juice industry. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrodeoxygenation of guaiacol. The catalytic material was modified with metallic nanoparticles of Pt. The catalysts were characterized by means of X-ray diffraction, N2 isotherms, XPS, SEM and TEM. Good structure, narrow pore size distribution and high platinum dispersion were achieved in the synthesized catalysts. The objective of this investigation is the evaluation of the catalytic activity and to compare it with SBA-15 support studied previously. The catalyst presented excellent performance for biofuels generation.Item New catalyst source applied in biofuel manufacturing(2020) Rivoira, Lorena Paola; Ledesma, Brenda Cecilia; Gómez Costa, Marcos Bruno; Beltramone, Andrea RaquelA clean energy revolution is taking place all over the world in pursuit of replacing oil. This work stands out an environmental point of view by proposing biomass wastes from different industrial areas to produce not only a biofuel but also as raw material to synthetize the catalyst involved in the HDO reaction. In this way the process ceases to rely on the antiquated and obsolete linear economy where products, services, wastes, materials, water and energy have a beginning and an end to become a process with greater tendency to the modern circular economy, closely related to the idea of sustainability. Products, materials and resources are expected to last as long as possible while minimizing waste as much as possible too. Agricultural and forestry waste are available everywhere being a low cost raw material and it is possible to provide added value to the organic wastes of small and medium size enterprises. The hydrodeoxygenation (HDO) of guaiacol has been performed in a batch reactor under 12 atm of H2 and different temperatures over activated carbon synthetized from orange peel discarded from juice industry. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrodeoxygenation of guaiacol. The catalytic material was modified with metallic nanoparticles of Pt. The catalysts were characterized by means of X-ray diffraction, N2 isotherms, XPS, SEM and TEM. Good structure, narrow pore size distribution and high platinum dispersion were achieved in the synthesized catalysts. The objective of this investigation is the evaluation of the catalytic activity and to compare it with SBA-15 support studied previously. The catalyst presented excellent performance for biofuels generation.Item HDT process performance over noble metal-mesoporous catalysts(2022) Vallés, Verónica Alejandra; Ledesma, Brenda Cecilia; Beltramone, Andrea RaquelThe greater concentration of market demand in the diesel range forces refiners to consider redirecting internal refinery cuts to new hydrocracking units to increase the contribution to the gasoline and diesel pool. These requirements drive advances particularly in hydrotreating technologies (HDT). The need to reduce the level of sulfur and polyaromatics in diesel fuel to values ??of a few ppm and the need to process heavy cuts with a high degree of aromaticity has motivated the appearance of new, more efficient processes. In recent years, bimetallic catalysts have received much attention, since they can combine two or more functions. The functionality of a catalyst can be due to active sites generated by supported metals and the interaction with the support. Pt-Pd catalysts have been extensively studied in order to improve tolerance to sulfur and other contaminants. They showed higher activity, stability and resistance to poisons compared to monometallic Pt or Pd catalysts. In bimetallic catalysts, the formation of the alloy creates electrondeficient species, more resistant to poisoning, in the case of Pd, which alone or alloyed with Pt, has a high hydrogenating and thio-resistant capacity and has begun to be used in industrial dearomatization units. The objective of this work is to evaluate the activity of all the synthesized catalysts in typical catalytic hydrotreating reactions. Performing first a kinetic study in a Batch reactor to the best catalysts that will then be tested in a continuous flow reactor in operating conditions close to industrial ones. With this objective, catalysts supported on SBA-16 were synthesized. This mesoporous has a high surface area and good characteristics of thermal stability, against the conditions set. The support was modified by incorporating Al indirectly and then impregnated with Ir, Pt and Pd. The behavior of the synthesized catalysts was studied against a commercially used catalyst and another support widely used in the industry, such as alumina. The catalysts were characterized by XRD, FTIR, NMR, TPR and N2 adsorption- desorption isotherms.