The synthesis of mesoporous materials in macroscopic scale, as for example, the monoliths, has been of great interest in view of the wide range of applications that this material holds. Thus, this work consists of the production of silica monoliths for the purpose of they being used in the carbon dioxide (CO2) adsorption process. The adsorbents were prepared in pure form and also with addition of heteroatoms: Al, Ti and Zr. The samples were then functionalized with pentaethylenehexamine (PEHA) by the wet impregnation method. The materials were characterized by the following techniques: X-ray diffraction (XRD), textural analysis, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Thermogravimetry (TG/DTG). The analyses indicated that the materials synthesized with heteroatom incorporation presented a disordered pore structure and high surface area (1387 m2/g for sample Ti/M1). In addition, they showed a significant increase in adsorption of CO2 relative to their parent sample, a fact that is not much explored in the literature. The CO2 adsorption performance tests were carried out at 30 ºC and atmospheric pressure. All functionalized materials demonstrated improved CO2 adsorption capacity relative to their starting samples. Adsorption capacities up to 111.3 mg/g were found in this work, which makes the materials developed promising candidates for the capture of CO2.

In the present report, Al-SBA mesoporous materials were investigated for use as water adsorbents. Different precursors for aluminum were investigated: aluminum sulfate and nitrate, boehmite, and aluminum tri-sec-butoxide. Furthermore, three different procedures for addition of the silica and alumina sources were tested. Samples were characterized by nitrogen adsorption to observe their textural characteristics and by thermogravimetric desorption of water to address their performance. The sample synthesized with aluminum tri-sec-butoxide as aluminum precursor and a pre-hydrolysis step of the silica source presented the highest adsorption capacity: 1057 g.kg-1. It was also observed that water attaches more strongly to Al-containing samples than to pure silica, and that water adsorption capacity is more related to the pore volume of samples than to their surface area. This work has shown that functionalizing SBA-15 materials with aluminum is a promising strategy for producing water adsorbents with improved performance and potential for many applications.

Mesoporous silica materials have been widely investigated for their great potential as competitive adsorbents and catalysts in different areas, due to their ordered and uniform porous structures and high surface area. In order to increase the availability of these materials, the need to granulate them becomes vital for an efficient performance in industrial units. This study reports the production and characterization of clay-free granules of SBA-15 mesoporous silica, by applying the extrusion technique. The suggested methodology uses only methocel as the organic binder, which is removed after calcination. The granulation process was successfully achieved, producing pure granules of SBA-15 mesoporous silica, in size of millimeters, with 8.3 MPa of compacting pressure (by axial crushing test). The surface area and pore volume of SBA-15 mesoporous silica granules (calcined at 800 ºC) were around 392 m2/g and 0.53 cm3/g, respectively.