Condensation minerals, catalytically active

Hybrid organic/mineral solid base catalysts bearing primary and tertiary amino functions have been used as catalysts in the Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate at 375 K in the presence of DMSO as solvent. Both catalysts exhibited a selectivity of approximately 100 % in ethyl trans-a-cyanocinnamate and could be recycled several times, after filtration and washing, without decrease in their catalytic performance.11711 The activity was found to be... 

The yield of the main product (I) can be increased by the catalytic regrouping of the products of the hydrolytic condensation of ethylethox-ysilanes. For this purpose, the products of hydrolytic condensation are treated with sulfuric acid or various types of clay (kil, askanite, bentonite) activated with mineral acids. It is accompanied by the following processes ... 

Hydrolytic co-condensation products underwent catalytic rearrangement in the presence of electrophilic catalyst presence [7-9]. Sulfonic cation-exchange resin or natural aluminosilicate-bentonite activated by mineral acid was used as this catalyst. 

Understanding of the modification from bulk liquid water behavior when water is introduced into pores of porous media or confined in the vicinity of metallic surfaces is important in technological problems such as oil recovery from natural reservoirs, mining, heterogeneous catalysis, corrosion inhibition, and numerous other electrochemical processes. Water in porous materials such as Vycor glass, silica gel, and zeolites has been actively under investigation because of their relevance in catalytic and separation processes. In particular, the structure of water near layer-like clay minerals [11,12], condensed on hydroxylated oxide surface [13], confined in various types of porous silica [14-22] or in carbon powder [23] has been studied by neutron and/or x-ray diffraction. 

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