UTN -FRC -Producción Académica de Investigación y Desarrollo - Comunicaciones a Congreso
Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/2433
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Item HaP / LP-SBA-15 Nanocomposite for efficient removal of fluoride from contaminated wáter(2020) López, Claudia G.; Anunziata, Oscar A.; Cussa, JorgelinaHydroxyapatite (HaP) composites and highly ordered large pore mesoporous silica, such as LP-SBA-15 (Large Pore-SBA-15), were developed, characterized by XRD, BET, FTIR and HRTEM, and applied properly to fluoride removal from contaminated water. The proposed procedure to prepare HaP/LP-SBA-15 was successful, which acts as supports to anchor the HaP crystals, in nanometer-scale (<12 nm), with higher fluoride retention from contaminated water. The free OH- groups of HaP nanocrystals, inside the host, permitted fluoride retention with high capacity. The fluoride holding activity was over 3 orders of magnitude higher than pure HaP.Item Mesopore carbón starch with acid properties: synthesis and characterization(2020) Martínez, María Laura; Anunziata, Oscar A.We have shown that a promising material with acidic properties can be successfully prepared from starch mesoporous carbon (SMC), functionalized with sulfated zirconia. The process of assembling P123, starch, zirconia, and silicon synthesized Zr-modified ordered mesoporous carbon. SMC and Zr-SMC were characterized by BET for their texture properties and, using Scanning Electron Microscopy (SEM), their morphology. Acidic properties were acquired by programmed thermodesorption of ammonia (NH3 TPD). These studies show that the Zr-SMCs material is mainly composed of mesopores with an average pore size of approximately 3.5 nm, high surface area and pore volume, and has medium to strong acidity properties.Item Super-acid sulfated/zirconium-containig nanostructured carbons(2020) Martínez, María Laura; Anunziata, Oscar A.In this work, we report the successful preparation of a superacid mesoporous carbon functionalized with sulfated zirconia (SZr-C). SZr-C has a surface area of approximately 1300 m2 g-1, and the total pore volume of 0.94 cm3g-1, composed mainly of mesoporous with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did reveal Zr isolated species. According to the data collected by infrared spectroscopy (FTIR), of pyridine desorbed at various temperatures, the total number of acidic sites was 2.36 mmol/g and the distribution in weak- medium, strong and super acidic sites was determined. The activity in the methylation of aniline indicated that the acid sites are strong, and have not redox properties.Item Synthesis and characteristics of magnetite containing-cmk-3 and its application in hydrogen storage(2020) Juárez, Juliana M.; Venosta, Lisandro F.; Gómez Costa, Marcos B.; Anunziata, Oscar A.In this work, we report the synthesis and characterization of iron oxide nanoparticles (Magnetite) supported on CMK-3. The materials were characterized by XRD, SEM, TEM, XPS and magnetization studies. A large amount of the iron incorporated as iron oxide nanoparticles was in the magnetite phase. The incorporation of magnetite on the CMK-3 carbon surface significantly improved the hydrogen storage capacity (4.45 wt. % at 77 K and 10 bar) compared to the CMK-3 structure (2.20 wt% at 77 K and 10 bar). Magnetite nanoparticles play a key role in H2 adsorption.Item Superacid mesoporous carbón base don sulfated Zr(2020) Anunziata, Oscar A.; Martínez, María LauraIn this brief communication we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia. The process of assembling P123, starch, zirconia and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. Zr-SMC has a surface area of approximately 1300 m2 g-1, and the total pore volume of 0.94 cm3 g-1, composed mainly of mesopores with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Through the thermodesorption of the pre-adsorbed ammonia in the sulfated Zr-SMC, the total ammonia retained is 1.80 mmol / g at high temperature, exhibiting medium to strong acidity.Item Multiple-wall carbón nanotubes obtained with mesoporous material decorated with cerio-zirconium(2020) Martínez, María Laura; Anunziata, Oscar A.In this work, Ce-Zr-SBA-15 has been used directly as a catalyst for the synthesis of multi-vall carbon nanotubes (MWCNT) through Chemical Vapor Deposition (CVD). In addition to cerium oxide, it contains zirconium oxide Nano crystallites, which act as catalysts for carbon nanostructures. The catalytic performance of this material was evaluated for the decomposition of ethanol at 900 °C, with N2 flow. The structural characterization of the resulting catalyst was carried out by means of SEM and XRD. The decomposed carbon of absolute ethanol diffuses through the surface of the nanostructured material and precipitates in carbon structures called multiple-walled nanotubes, which could be visualized/detected/identified by TEM, showing diameters of the carbon nanotubes that range from 15 to 25 nm.Item Direct synthesis and characterization of mesoporous carbon CMK-3 modified with zirconia applied in energy storage(2020) Venosta, Lisandro F.; Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.In this work, we report the synthesis and characterization of the nanostructured carbon material (CMK- 3) modified with zirconium oxide synthesized by a new direct synthesis technique. The aim of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were successfully synthesized and characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. This material is promising in the application of hydrogen adsorption for energy storage. Zr-CMK-3 material significantly improved H2 storage behavior (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). A hydrogen adsorption mechanism was proposed and the role of the Zr+4 cation in hydrogen absorption was discussed. The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction) [1]. The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The interaction of the induced dipole in a second layer adsorbs more hydrogen molecules because the strong interaction of the metal particles takes up dipole-induced forces on the hydrogen molecules. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases. The procedure for this adsorption is still under investigation and optimization. The hydrogen storage behavior in Zr-CMK-3 can be optimized by controlling the size of the metal particles, the dispersion and the nature of the support.Item Síntesis directa del carbón mesoporoso ordenado cmk-3 modificado con circonio aplicado en almacenamiento de energía(2020) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.; Venosta, Lisandro F.En este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno.Item Synthesis, characterization and application of mesoporous materials in the controlled release of ibuprofen(2020) Cussa, Jorgelina; Anunziata, Oscar A.Drug delivery systems consist of an active ingredient and a carrier system that can direct the release of the drug to the appropriate site and in the appropriate amount. The characteristics that these vehicles must meet are low toxicity, optimal properties for drug transport and release, and long half-life. Three mesoporous materials are reported in this work, the first one containing lattice aluminum; named Al-Si/SBA-3; the second one containing magnesium; named Mg-SBA-3, and the third one named LP-SBA-15. These materials were characterized by X-ray diffraction, resulting in hexagonal porous nanostructures, with lattice parameters of 3.63 nm for Al-Si/SBA-3 (without significant changes in the periodicity of the lattice). LP-SBA-15 is a novel large porous nanomaterial. It is encouraging the results of the application of these materials as host-transporters in the study of the modified release of Ibuprofen. LP-SBA-15 appears to be the most promising delivery system for IBU and its controlled release.Item Preparation, characterization and mathematical modeling of keterolac release conteined in lpsba-15 host(2021) Cussa, Jorgelina; Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.Drug-controlled release systems can keep the level of drugs in precise doses in the body above the optimal level and with low toxicity. We propose the LP-SBA-15 nanomaterial as a promising new host for drug delivery systems because of its high biocompatibility, in vivo biodegradability, and low toxicity. Ketorolac-LP-SBA-15 was prepared and characterized by XRD, FTIR, UV-Vis DRS, TEM, and texture analysis, determining the adsorption capacity and its release, achieving the required therapeutic efficacy. The host shows ordered mesoporous nanochannels with a diameter of 11-12 nm, maintaining the structure with the incorporation of Keto. The mechanism of drug release the LP-SBA-15 host was evaluated. Different mathematical models were used to adjust the experimental data, being the Ritger-Peppas model followed by the Weibull model the best ones. In this work, we show a promising drug storage material for effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. Studies indicate that KETO was adsorbed on the channel surface of LP-SBA-15 without affecting the structure or chemical composition of KETO. Controlled drug delivery systems can achieve precise delivery at the time and place of destination, keeping the concentration of the drug at points in the body within the optimal range and below the toxicity threshold. The study also demonstrates the storage capacity and release properties of LPSBA- 15 containing KETO. The release of KETO contained in LP-SBA-15 can offer a significant improvement in the controlled release of the drug and the analgesic and anti-inflammatory effects, positively influenced, by the links formed between the host and drug molecules and by diffusion through the host porosity. The promising results we obtained for the release of the drug thoroughly using the new material, reaching a rapid initial release rate, and maintaining a constant rate afterward, allow us to maintain the concentration of the drug in the therapeutic efficacy range, applying it largely to the treatment of diseases that require a rapid response.