The potential usage of hematite nanoparticles as heterogeneous catalysts in aquathermolysis was investigated in this work. The desulfurization of thiophene was studied to investigate the catalytic activity of hematite in the aquathermolysis of heavy oil. It was found that reaction conditions, e.g., reaction time and temperature, ratio between thiophene and water, hematite nanoparticle size, catalyst concentration, and the presence of hydrogen donors, influenced the ability of hematite nanoparticles to decompose thiophene. Experimental results showed that thiophene conversion was increased with reaction time, temperature and catalyst concentration but decreased with thiophene/water ratio and particle size. Further analysis showed that the activity of the hematite nanocatalyst was also reduced in the presence of hydrogen donors. This is because hydrogen donors occupy the catalyst surface and block the catalytic sites. Furthermore, FTIR and XRD analyses revealed that thiophene underwent oxidative

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NaY zeolite particles with a high surface area of 723 m 2 /g were synthesized by a hydrothermal method. Adsorption isotherms of pure gases CO 2 and N 2 on the synthesized NaY particles were measured at temperatures 303, 323, 348, 373, 398, 423, 448 and 473 K and pressures up to 100 kPa. It was found that the adsorption isotherm of CO 2 on the synthesized zeolite is higher than that on other porous media reported in the literature. All measured adsorption isotherms of CO 2 and N 2 were fitted to adsorption models Sips, Toth, and UNILAN in the measured temperature/pressure range and Henry's law adsorption equilibrium constants were obtained for all three adsorption models. The adsorption isotherms measured in this work suggest that the NaY zeolite may be capable of capturing CO 2 from flue gas at high temperatures. In addition, isosteric heats of adsorption were calculated from these adsorption isotherms. It was found that temperature has little effect on N 2 adsorption, while it presents marked decrease for CO 2 with an increase of adsorbate loading, which suggests heterogeneous interactions between CO 2 and the zeolite cavity. KeywordsAdsorption isotherm · Isosteric heat of adsorption · Zeolite · CO 2 capture Nomenclature b Parameters for Sips model, kPa −1 c Parameters for UNILAN model, kPa DQ Standard deviation, % k Number of experimental data

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This paper reports the results of an experiment on the synthesis and electrodeposition of iridium oxide nanoparticles for the fabrication of a pH sensor. Iridium oxide nanoparticles with mean diameter in the range of 1–2 nm were successfully synthesized and electrodeposited on stainless steel substrate by cyclic voltammetry. It was observed that the surface of the deposited iridium oxide film exhibited porous and rough surface morphology. The iridium oxide electrode thus prepared displayed excellent pH sensitivity, obtaining super-Nernstian behavior with pH sensitivity value of −72.6 mV/pH.