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چکیده
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Recently, there have been significant extensive progress to synthesize
novel types of ordered porous materials for catalysis, separations, etc. Among those, ordered mesoporous material with microporous walls are promising in a sense that while mesopores perform as channels for the reactant transport with little diffusion limitation, micropores in the wall perform as active sites for reactions or storage of the molecules.
In this research, we focused on the SBA-15 material, which is a highly ordered mesoporous silica material with micropores existing in the wall. Hence, the influence of physico-chemical synthesis parameters on textural, structural properties of SBA-15 materials under short ripening time was investigates. By a judicious altering of the different parameters in the synthesis condition, including temperature, time, stirring rate, precursor ratios, acidity and additives, a fine morphology can be tailored.
Results indicate that the variations in synthesis conditions like stirring rate, molar ratio and acid concentration, leads to several morphologies, such as fibers, helixs, beans and sphericals in the form of particles of various sizes. Also, Different mesostructured odrered are obtained by alteration synthesis conditions.
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In low acid medium (0.5 M), S-R12h0.5M-H12h sample prepared by using 12 hours for the ripening step and 12 hours for aging step process show best quality as compared to conventioal SBA-15 under short possible period. besides, the RS-3M sample synthesized from low-cost RHA and aqueous solution of 3M HCl exhibited nearly similar silica recovery and ordered structure in comparison with the conventional SBA-15 And under the aforementioned conditions, RHA can be a potential replacement for TEOS as silica source.
Outcomes of Alcoholes presence in the synthesis solution over SBA-15 morphology depend on the diffusion of these organic molecules towards hydrophobic part of the micelles. The results show that, both the 1-butanol and tert- buta
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