Heterogeneous catalysis mechanism comparison

The heterogeneous catalysis of such a reaction, is a challenge which has shown a remeurkable expansion since the discovery of titaniiun-containing zeolites and their catalytic properties in the activation of hydrogen peroxide [1]. The development of this catalysis has however taken place to the detriment of others. Thus, despite patents [2-5], the use of solid acids, such as zeolites or clays, has never been the subject of academic work. The absence of kinetic results is particularly prejudicial to a valuable comparison of the various types of catalysis. We present, here, a kinetic approach to the study of the hydroxylation of phenol by hydrogen peroxide over solid acids. This shows unexpected behaviour, which calls into question the mechanism of the acid catalysis. A more accurate comparison with the catalysis by titanosilicates will be deduced. 

Mechanisms for Aqueous Phase Heterogeneous Catalysis and Electrocatalysis A Comparison with Heterogeneous Catalytic Reactions... 

Characterization of active sites. In more fundamental studies, the reaction rateshould not refer to the mass of catalyst or metal, but to the active site. The detection of active sites, including the density (A) and the intensity of active site is a central subject of heterogeneous catalysis. The turnover number or turnover frequency (TOF) on per unit active site per unit time under the given conditions can be calculated according to active site determined. At present, TOF is a basis to obtain the intrinsic activity of metals as well as determine the reaction mechanisms. Due to the dimension of TOF is the reciprocal of second, the comparisons of the... 

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