A series of mesoporous materials have been synthesized in an acid medium, with various structures, such as SBA-15. These materials have many properties which make them potential catalysts. Among these we highlight their high surface areas and pore walls relatively thick, resulting in a greater hydrothermal stability. This work aims at the synthesis and characterization of molecular sieve SBA-15 with molar composition: 1.0 TEOS: 0.017 P123: 5.7 HCl: 193 H2O and Co/SBA-15 and catalysts for the reaction of Ru/Co/SBA-15 Fischer Tropsch process. The materials were characterized by the techniques of X-ray diffraction (XRD), chemical analysis by X-ray spectrometry, energy dispersive (EDX) and Nitrogen adsorption (BET method). X-ray diffraction showed that the calcined cobalt catalyst did not modify the structure of SBA-15 and that Co was present under the form of Co3O4 in the catalyst. The addition of cobalt in the SBA-15 decreased the specific superficial area of the molecular sieve.

New sources of silica as a replacement for TEOS in the synthesis of SBA-15 are been performed by various research teams worldwide. The aim of this work is to describe the synthesis and characterization of SBA-15 made with chocolate B clay as an alternative source of silica by the hydrothermal method. Samples of classic SBA-15 were made with the traditional TEOS method. The samples of the two silica sources were characterized by DRX, EDX, and BET to evaluate the effects of the silica source on the synthesis of the molecular sieve. The chocolate B clay was efficient in the formation of the molecular sieve structure, but there was a great reduction in the surface area and total pore volume in comparison to the surface area of classic SBA-15.

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The efficiency of as-synthesized and calcined mesoporous silica, using clay as a silica source, to remove the reactive blue BF-5G dye was investigated. The materials were characterized by X-ray diffraction (XRD) analysis, energy-dispersive X-ray fluorescence (ED-XRF), and Fourier-transform infrared spectroscopy. The kinetic and adsorption isotherms were also studied. The XRD and ED-XRF results showed that the Chocolate clay is rich in SiO2 (69.4%) and has a large amount of other oxides, which can be eliminated by acid leaching. According to the characterization results, the MCM-41 synthesis was effective and produced a highly-ordered material. The kinetic study showed the adsorption corresponded predominantly to the pseudo-second order model. Adsorption equilibrium was reached after 3 h, and the data were better fitted to the Freundlich model. Furthermore, both samples obtained satisfactory removal results, being potential adsorbents having reduced cost due to the use of an alternative silica source.

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