Modified versions of MCM-41 and SBA-15 were obtained from sucrose by carbon deposition. The ability of the resulting materials, MCM-41 CC and SBA-15 CC, to remove Rhodamine B from aqueous solutions was evaluated. TG/DTG, XRD, Nitrogen Adsorption (BET), and SEM were used to characterize the materials. Adsorption was investigated by finite bath studies. To characterize the adsorption behavior and mechanism, kinetics and equilibrium were assessed. MCM-41 CC provided the best adsorption results: adsorptive capacity of 11.91 mg of dye/g of material and 91.95% w/v dye removal (C = 50 mg L). The sucrose particles interacted well, to result in improved area and micropore volume. Hence, carbon deposition can afford materials with increased adsorptive capacity depending on the sieve employed during their preparation.
Tin incorporation in high-silica ZSM-12 zeolite was evaluated using different concentrations of tin and different structure-directing agents (SDA), in order to be used in the glucose isomerization reaction in fructose. The tetraethylammonium hydroxide SDA successfully formed the structure of the high silica zeolite ZSM-12; however, in this system, the addition of Sn prevented the formation of the ZSM-12 zeolite. Therefore, tetraethylammonium bromide was used as SDA, but the syntheses of high-silica ZSM-12 zeolite without and with tin incorporation were not effective. Then methyltriethylammonium chloride was used as SDA, and the high-silica ZSM-12 structure was formed only with the incorporation of tin. The samples with ZSM-12 structure and different concentrations of tin were evaluated in reaction of glucose conversion to fructose. It was found that the sample with the lowest tin content ( Sn / Si = 0 . 005 ) achieved the highest glucose conversion and the highest fructose yield.
The synthesis of SSZ-13 was studied by evaluating the influence of two types of crystallization seeds with CHA structure (S 1 seeds prepared in fluoride medium and S 2 seeds by the conversion of zeolite Y), SiO 2 /Al 2 O 3 (28, 40, 60 and 100) and OH/SiO 2 (0.6 and 0.8) ratios. Choline chloride was used as the structure-directing agent and the crystallizations occurred at 140 ºC from 24 to 96 h. S 1 seeds led to the coexistence of zeolites SSZ-13 and P, while S 2 seeds promoted in all SiO 2 /Al 2 O 3 ratios and OH/SiO 2 = 0.8, the formation of pure SSZ-13 after 24 h. The SSZ-13 samples are formed by clusters of crystals with cuboid-like morphology and exhibited textural properties typical of CHA framework. SSZ-13 zeolite led to a decrease in the temperature and the activation energy required for the degradation of ultra-high molecular weight polyethylene polymer, demonstrating its efficiency as catalyst in this process.
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