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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.

The objective of this work is to describe the production of bifunctional catalysts using the incipient humidity method, producing catalysts with 15 wt.% cobalt supported in SBA-15 molecular sieve, to be applied in the Fischer-Tropsch (FT) reaction. The originality of this work is its focus on the use of a 15 wt.% Co/SBA-15 catalyst in FT synthesis in slurry reactors. The deposition of cobalt over SBA-15 support was accomplished by impregnation with a 0.1-M aqueous solution of cobalt nitrate. The Fischer-Tropsch synthesis was carried out with the catalyst at 240 °C and 20 atm, under a COH 2 atmosphere (molar ratio= 1), in a slurry reactor for 8 hours. X-ray diffraction measurements showed that the calcined cobalt catalyst did not modify the structure of SBA-15, proving that Co was present under the form of Co 3 O 4 in the catalyst. The addition of cobalt in the SBA-15 decreased the specific superficial area of the molecular sieve. The 15 wt.% Co/SBA-15 catalyst had a 40% CO conversion rate and a high selectivity towards the production of C 5 + (53.9% after 8 hours).

This work aimed to produce 5% (w/w) molybdenum and nickel catalysts, supported in SBA-15 molecular sieve, and evaluate their application in the synthesis of biodiesel. The catalysts were prepared by physical dispersion and were characterized by X-ray diffraction, X-ray energy dispersion spectrophotometry, and N 2 adsorption-desorption. Transesterification reactions were carried out to evaluate the activity of the catalyst. The synthesis was effected by using a system comprised of a polytetrafluoroethylene batch reactor jacketed with a piece of stainless steel working at 600 rpm. The reactions were conducted at 473K for 4 hours, using a soybean oil/ethanol molar ratio of 1/12, and 5% of catalyst based on the mass of oil used. After characterization, the catalysts were subjected to catalytic tests to check the reaction conversion parameters obtained by gas chromatography. The kinematic viscosity and density of the biodiesel samples were then determined. The chromatography results were not satisfactory for the test with SBA-15 (pure silica). The conversion to esters obtained was 5%, which can be due to the formation of silanol groups (Si-OH) on the silica surface, which are considered Brönsted acidic sites. However, in terms of strength, the acidity of silanol is usually either low or moderate. Mo/SBA15 and Ni/SBA-15 catalysts yielded conversions to biodiesel as high as 96.57% and 84.67%, respectively.