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The adsorption behavior of eosin yellow (EY) from aqueous solution onto γ-Al 2 O 3 nanoparticles in batch technique was studied. γ-Al 2 O 3 NPs was prepared and characterized by SEM, TEM, XRD and FTIR analysis. The effect of pH, dosage of adsorbent, contact time, temperature, and the initial concentration of dye was investigated. The maximum amount of dye removal found about 99.36% at pH 4, the adsorption dose 1 g/L, with the initial dye concentration of 100 mg/L, and the temperature of 25˚C, with contact time 120 min. The adsorption behavior of the eosin yellow dye is applicable to Langmuir isotherm model, with the maximum sorption capacity of 47.78 mg/g of γ-Al 2 O 3 . The kinetic data also described by the pseudo-second-order model with a correlation coefficient (0.9999), and the mechanism of the process showed a multi-linear steps and the intra-particle diffusion was not only rate controlling step. The adsorption process was endothermic with positive enthalpy of 121.8 kJ/mol, and showed spontaneous process with a mean free energy −5.19 kJ/mol, and increase randomness, 369.77 J/mol. k, at the adsorbent solution interface. The adsorption process was chemisorption in nature The activation energy estimated from Arrhenius and modified Arrhenius is 40.9 kJ/mol, 106.37 kJ/mol respectively. The sticking probability of EY onto Al 2 O 3 NPs very high estimated from the value of S * < 1, (4.82E−19).

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This work describes a method to synthesize free-standing nanoplatinum wires (8-25 nm diameter and 30-100 nm length) fabricated by CO (200 Torr)/water (20 Torr) under a high-pressure Hg lamp at 300 K, for 36 h, induced from H 2 PtCl 6 impregnated with FSM-16 (2.7 nm). On the other hand, stabilized platinum nanoparticles (spherical) grown by consecutive reductive carbonylation of a CO (200 Torr) and CO (20 Torr)/water (2 Torr) system at 323 K exhibited mean particle sizes of 2-10 nm. The structure, dispersion behavior, and surface morphology of the materials have been characterized by temperature programmed surface reaction of CO (TPSR), temperature programmed reduction (TPR), N 2 sorpitometry, and transmission electron microscopy techniques. The Pt nanowires showed a higher catalytic activity toward the water-gas shift reaction (WGSR) than that of nanoparticles. It has been shown that the activity does not depend on the structural and morphological characteristics of Pt/FSM-16 such as specific surface area or primary crystallites size but depends on Pt geometry. Investigation of the surface intermediates observed by in situ Fourier transform infrared spectroscopy formed over Pt nanowires and Pt nanoparticles during the WGSR depicted the developing of unidentate formate species on the former and carbonates on the latter. TPSR demonstrated the facile interaction of CO with nanowires (243-373 K) at lower temperatures, presumably dissociatively, than with nanoparticles (243-493 K). The same result was accomplished using TPR, comprehending that complete reduction was attained at 723 K for the former, but it did not reach completion until 873 K for the latter. This indicated that cationic Pt plays a crucial role in catalyzing WGSR at 323 K. Other issues regarding the binding of CO on Pt particles, declining activity with temperatures, and CO cluster bonds either on Pt nanoparticles or nanowires were also discussed.