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ZrO 2 -SBA-15 materials with different ZrO 2 loadings (12.5, 25, 37.5, and 50 wt.%) were prepared by incipient wetness impregnation of SBA-15 silica with zirconium (IV) n-propoxide solution and characterized by N 2 physisorption, IEP, and XRD. It was found that the dispersion of zirconia in ZrO 2 -SBA-15 samples decreased with ZrO 2 loading. Nevertheless, about 70-90% of the available support surface was covered with deposited ZrO 2 species leading to high zirconia surface, significantly higher than areas of the traditional bulk ZrO 2 supports. ZrO 2 -SBA-15 materials were used to prepare Mo catalysts, which were characterized (N 2 physisorption, XRD, TPR, and HRTEM) and tested in 4,6-dimethyldibenzothiophene hydrodesulfurization (HDS). Characteristics of Mo species deposited on ZrO 2 -SBA-15 materials with 25-50 wt.% of ZrO 2 and their intrinsic HDS activities were found to be similar to those of the Mo catalyst supported on pure ZrO 2 . Thus, it is shown for the first time that prepared ZrO 2 -SBA-15 materials combine chemical properties of zirconia, attractive for many catalytic applications, with excellent textural characteristics of SBA-15.

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The use of mask and face shield has been established as one of the main preventive measures for the control of COVID 19 spread. In Mexico, as well as in other regions of the world, 3D printing has been employed for the design and production of masks and face shields as personal protective equipment (PPE). These models have been fabricated mainly by the makers, industries, and university communities; therefore, it is necessary to analyze the feasibility of the 3D printed PPE to understand its advantages and limitations. In this work, some characteristics of masks and face shields fabricated by additive manufacturing were studied to explore their viability as protection against flow fluids similar to human sneeze. In the present paper, the PPE was designed, and 3D printed utilizing three types of polylactic acid (PLA) as base material. The morphology and the surface elemental analyses of sectioned samples were analyzed by scanning electron microscopy (SEM) and energy dispersion x-ray spectroscopy (EDS). Showing spacing between printed layers, porous areas, and dispersed copper particles. On the other hand, a computational fluid dynamics (CFD) simulation was carried out, the results demonstrated the importance of using PPE for protection of a possible exposure to a “contaminated” aerosol and human sneeze. Based on the abovementioned results, it is possible to consider the commercial PLA as suitable material for the manufacturing of PPE due to its capability to be disinfected employing isopropanol, ethanol, or commercial disinfectants.