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In this study, several ZnO catalysts were prepared using different zinc sources as precursors. The different catalyst mor- phologies obtained were used to degrade photocatalytically a methyl orange (MO) dye solution, which was used to model wastewater pollution. The precursors, Zn(CH3COO)2, ZnCl2 and Zn(NO3)2, were individually added to a solution containing cetyltrimethylammonium bromide (CTAB) and sodium hydroxide (NaOH) for the hydrothermal synthesis of ZnO. After the hydrothermal reaction, the samples of ZnO were filtered, washed, dried at 110?C and calcined at 550?C, resulting in the formation of the rod-like (designated ZnO(I)), the rice-like (designated ZnO(II)) and the granular-like (designated ZnO(III)) catalysts. The catalysts were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM) and their UV-visible diffuse reflectance spectra (UV-Vis DRS). The results indicate that the photocatalytic degradation of the MO solution, after 60 min of UV irradiation, can reach percentages of 40%, 96% and 99% using the catalysts ZnO(I), ZnO(II) and ZnO(III), respectively. The morphology of the ZnO catalyst had an ap-
Hydrogen production through steam reforming of ethanol (SRE) over Mg modified Co-based catalysts supported on mesoporous SBA-15 was studied herein to evaluate the catalytic activity and the behavior of coke deposition. The CoyMgx/SBA-15 catalysts are obtained according to the steps of consecutive impregnation of Mg (x = 5 and 10 wt%) to be incorporated on SBA-15 and then follow the loading of Co (y = 10 and 20 wt%) using the incipient wetness impregnation method. The catalysts are characterized by using X-ray diffraction (XRD), temperature programmed reduction (TPR), transmission electron microscopy (TEM) and BET techniques. Also, the spent catalysts are further characterized by using XRD and TEM. The catalytic activity of the SRE is evaluated in a fixed-bed reactor under 22,000 h-1 GHSV and with an H2O/EtOH molar ratio of 13. All the CoyMgx/SBA-15 catalysts present a mesoporous structure, even after the SRE reaction. The optimum catalyst of Co20Mg5/SBA-15-H650 comes from the high loading of Co and high reduction temperature pretreatment, which show a high catalytic activity and stability at 550°C with a hydrogen yield (YH2) up to 5.78 and CO selectivity around 3.10%.