Active phase, catalysis carbon stabilization

Most of the adsorbents used in the adsorption process are also useful to catalysis, because they can act as solid catalysts or their supports. The basic function of catalyst supports, usually porous adsorbents, is to keep the catalytically active phase in a highly dispersed state. It is obvious that the methods of preparation and characterization of adsorbents and catalysts are very similar or identical. The physical structure of catalysts is investigated by means of both adsorption methods and various instrumental techniques derived for estimating their porosity and surface area. Factors such as surface area, distribution of pore volumes, pore sizes, stability, and mechanical properties of materials used are also very important in both processes—adsorption and catalysis. Activated carbons, silica, and alumina species as well as natural amorphous aluminosilicates and zeolites are widely used as either catalyst supports or heterogeneous catalysts. From the above, the following conclusions can be easily drawn (Dabrowski, 2001) ... 

Considering the hydrophilic properties of the support, the effectiveness of polysaccharide aerogel microspheres as catalyst support was evidenced in the so-called Supported Aqueous Phase Catalysis [131]. The stability of the catalyst obtained was investigated in terms of textural stability and catalytic activity in the reaction of substitution of an allyl carbonate with morpholine catalyzed by the hydrosoluble Pd (TPPTS)3 complex [132]. 

Adsorption of Terminal Olefins on H Si(m) Since 1995 when Linford etal. first reported the fabrication methods of long alkyl chains (>10 carbons) [6], the reaction between H Si(lll) and terminally double-bonded olefins (1-alkenes) has been accepted as a practical method of organic deposition. The adlayer of long alkyl chains is robust and convenient to stabilize Si surfaces and to make modifications over the adsorbates. The deposition reaction was activated by the coexistence of a radical initiator in liquid phase [6], by heating [6], by light irradiation [46-48], or by using Lewis-acid catalysis. Use of diluted olefins in an inert solvent (such as saturated alkanes) improves the quality of the alkyl adlayer [49]. 

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