Illite-smectite clay is a new mixed mineral of illite and montmorillonite. The ability of nano illite/smectite clay to remove Pb(II) from slightly polluted aqueous solutions has been investigated. The effects of pH, contact time, initial concentration of Pb(II), nano illite/smectite clay dosage, and temperature on the adsorption process were studied. The nano illite/smectite clay was characterized by X-Ray Diffraction (XRD), Fourier transform infrared spectrometry (FTIR), and Scanning electron microscopy (SEM). The results showed that Pb(II) was adsorbed efficiently by nano illite/smectite clay in aqueous solution. The pseudo-second-order kinetic model best described the kinetic of the adsorption, and the adsorption capacity of nano illite/smectite (I-S m ) clay was found to be 256.41 µg·g −1 for Pb(II). The adsorption patterns followed the Langmuir isotherm model. Thermodynamic parameters, including the Gibbs free energy (∆G), enthalpy (∆H), and entropy (∆S) changes, indicated that the present adsorption process was feasible, spontaneous, and endothermic in the temperature range of 298-333 K.

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The interaction of gas phase atomic hydrogen with chemisorbed oxygen on Ru(001) and RuOx films has been investigated by means of Auger electron spectroscopy and thermal desorption spectroscopy at surface temperatures between 120 and 320 K. Although molecular hydrogen does not adsorb on oxygen saturated Ru(001) or RuOx films even at 120 K, atomic hydrogen reacts with oxygen on Ru(001) surfaces, and both D2 and D2O desorb at temperatures below 500 K. The 2Dgas+Oad→D2Ogas reaction is approximately six times faster at 310 K than at 120 K. For RuOx films, a unity reaction probability was found at oxygen coverages above 3 monolayers (ML), while it decreased to 0.4 at Θ0<3 ML. Such variation can be attributed to a change in the structure of the oxide film. The reaction probably follows an Eley–Rideal mechanism where gas phase atomic hydrogen reacts with oxygen prior to thermal accommodation within the surface. The desorption of water is the rate limiting step at surface temperatures below 200 K, whereas the formation of water is the rate limiting step at higher temperatures.