Desarrollo, Producción e Innovación en la Investigación científica

Permanent URI for this communityhttp://48.217.138.120/handle/20.500.12272/2392

Browse

Author: search.filters.author.Beltramone , Andrea RaquelSubject: search.filters.subject.Synthesis

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Synthesis of SBA-1, SBA-3 and SBA-7 mesoporous materials. Study of the effect of time and temperature.
    (Universidad Tecnológica Nacional., 2016) Martínez , María Laura; Ponte , María Virginia; Falcón , Horacio; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Ponte , María Virginia
    In recent years, physicists, chemists and engineers have focused their research on the design of new functional materials. In the synthesis and control of materials in nanometer dimensions, the aim is currently directed towards the development of systems and devices that take advantage of chemical properties and physical principles, where their causes lie in the nanometer scale. Although there are numerous investigations about the synthesis of mesoporous materials from inorganic silicon salt, for example the synthesis of SBA-3. Ting et al [1] studied the synthesis of SBA-1; they obtained mesoporous SBA-1 with cubic structures, with a high porous system, by utilizing agents’ routers short chain structure such as the dodecyltrimethyl ammonium chloride. Recent research also showed that the formation of mesophases is affected by the presence of the counter ions and templates or surfactants can adopt a mesophase or other phases. So, Che et al. [2] found a phase shift 2D-hexagonal cubes from P6mm to Pm3n. We have published results for synthesis of SBA-3 with silica gel as silica source; we have found that the formation of mesophase is function of NaOH concentration in the dissolutions of silica gel. The influence of reaction temperature, time and NaOH concentration was investigated. During studies for the best synthesis conditions for synthesis of SBA-3, we also obtained SBA-1 and SBA-7 mesoporous materials.
  • Thumbnail Image
    Item
    Optimization of the synthesis of SBA-3 mesoporous materials by experimental desing.
    (Univesidsad Tecnológica Nacional., 2015) Ponte , María Virginia; Rivoira , Lorena Paola; Cussa , jorgelina; Martínez , María Laura; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Anunziata; Cussa , jorgelina; Rivoira , Lorena Paola
    SBA-3 mesoporous materials are characterized by hexagonal regular arrangements of channels with diameters >2 nm, high specific surface areas and high specific pore volumes. In the work reported herein, experimental design-response surface methodology (RSM) is used to model and optimize the synthesis conditions for SBA-3 mesoporous materials. In this study, we evaluate the influences of surfactant/silica source molar ratios, aging times, temperature and pH on the synthesis of SBA-3 mesoporous materials by analyzing the XRD intensities pertaining to the [100] signal. Response surfaces were obtained using the BoxeBehnken design, and the combination of reaction parameters was optimized. By applying statistical methodology, higher levels of the objective function (XRD intensities pertaining to the [100] signal) were obtained using cetyltrimethylammonium bromide (CTAB)/tetraethyl orthosilicate (TEOS) molar ratios of 0.07 and 0.16, HCl/TEOS molar ratios of 8 and 11, reaction temperatures of 35 and 45 ◦C and aging times of 12e24 h. The mesoporous SBA-3 samples obtained were characterized using small-angle X-ray powder diffraction (XRD), BET, FTIR and 29Si NMR-MAS, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).