Adsorption dissodative

The adsorption of hydrogen, ethylene, and CO on Pt(l 1 1) was extensively studied. Molecular hydrogen dissodatively adsorbs on the catalytic Pt(l 1 1) surface... 

The island mechanism assumes that adsorption takes place in wet conditions and H2O adsorbed on the carbon surface, is able to create water clusters or small water islands, where MM and oxygen first are dissolved in molecular form and later, depending on the pH, MM can dissociate to thiolate ion. Oxidation occurs due to the surface reaction between adsorbed thiolate ions and dissodatively adsorbed oxygen in water "islands" and/or between adsorbed MM and oxygen on a dry part of the carbon surfece. The product of reaction, DMDS, is adsorbed in a molecular form on the carbon surface (Fig. 35). 

In many cases of practical importance, the adsorbate molecule will dissodate on adsorption [H2 on many metals is probably the most well-known example see J. R. Roberts, Proc. Roy. Soc. London, A152, 445 (1935) O. Beeck and A.W. Ritchie, Disc. Faraday. Soc., 8, 159 (1950)], or occupy two sites by bonding at two... 

The differences in adsorption isotherms as th relate to the distinctimolecular adsorption of CO and the dissodative adsorptirm of Qj to form adsorbed atomic O is well described in standard text books. Ho e we will accept as feet diat in the catalytic oxidation of CO both reacting species are competitively adsorbed cm die same sites and that the product CO2 does not compete for adsorption on these sites. 

Another application for neutral, nonpolar stationary phases based on silica or organic polymers is the separation of weak adds or bases in their molecular form. Their dissodation is suppressed at the appropriate pH value The solute interactions with the stationary phase are determined solely by their adsorption and distribution behavior. The term ion-suppression nwde has been coined for this technique. In some areas of analysis, it provides an alternative to ion-exchange chromatography. 

Gross A, Scheffer M (1998) Ab initio quantum and molecular dynamics of the dissodative adsorption on Pd(lOO). Phys Rev B 57 2493... 

Gostein HG, Sitz GO (1997) Rotational state-resolved sticking coefficients for Hz on Pd(lll) Testing dynamical steering in dissodative adsorption. J Chem Phys 106 7378... 

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