Porous carbon investigations, additional

The pore sizes and volumes are a function of various parameters including the precursor material, the pretreatment of the precursor prior to carbonization, the carbonization process itself, and the activation process carried out after or simultaneously with the carbonization. To date, a variety of materials have been used for AC production, including coals [18], bio and agricultural products [19-23], polymeric materials [24], tires [25], etc. [26]. At the moment, the use of coals and agricultural byproducts seem to be the most widespread industrial production paths [27]. Often, porous carbons investigated in research function better than the commercially available carbons [28, 29]. The economic analyses of AC plants are very sensitive to production yield and the activation route. In addition to plant capacity, another... 

Lots of porous solids, such as porous carbons, porous silica, zeolites and porous organic frameworks, have been reported and investigated for gas sorption. Compared with these porous materials, PAFs show unique advantages of combining high surface area and excellent physicochemical stability. This is especially true for PAF-1, which has a high surface area of 5640 m g and could survive extreme conditions such as boiling in solvent or addition to cold basic or acidic solutions. ... 

Recently (ref. 3) the use of calcium as a catalyst of the carbon-CO, reaction, was investigated in the preparation of activated carbons. Two different porous carbon precursors were used and the porosity of the activated carbons obtained with and without calcium were compared. It was found that the addition of calcium to the CO,-carbon activation influences the gasification rate and the adsorption capacity of the resulting activated carbons. It was proposed that catalytic activation may be used to tailor the pore size distribution in a way which is not possible by the usual uncatalyzed activation process. 

Section 1 considers the methods of synthesis and physico-chemical properties of new types of inorganic sorbents (complex carbon-mineral sorbents, co-precipitated hydroxides, functional polysiloxane sorbents, porous glasses with controlled porosity, colloidal silicas, aluminium oxyhydroxide colloids, apatites). These sorbents are widely used in scientific investigations, in chemical practice and are important from a technological point of view. The presented results provide additional possibilities for the preparation of inorganic sorbents possessing unique adsorption and catalytic properties. Moreover, Section 1 presents the possibilities of the computational studies on the design of synthetic materials for selective adsorption of different substances. 

The investigations on the behavior of the monatomic alcohols have been confined almost entirely to methyl and ethyl alcohol, both of which show complete analogy in their reactions. In those cases where platinum electrodes were used and similar results were obtained both with and without porous separating cells, the decompositions are almost without exception oxidation processes. Being in the pure state poor conductors, the alcohols require strong currents for their electrolysis. The addition of potassium carbonate or dilute acid increases the conductivity of the solution, but of course influences the results. 

Taking into account all these factors, it has been found that the most appropriate supports for PFMFCs catalysts are carbon blacks of ca. 250 m g BFT surface area, and the most widely used is Vulcan XC-72R commercialized by Cabot. ° ° Due to the importance of the surface chemistry of these supports, and its influence in the supported active metal phase, ° ° different chemical modifications of the support have been also investigated. The chemical nature of the carbon surface produces different electronic interactions between the noble metals and the carbon support, and affects the metal particle morphology, and influences the catalytic activity. Additionally, during the last few years, new alternative materials to carbon blacks have also been used, especially on the basis of their porous structure (nanotubes, mosoporous carbons) or their microstructure (nano- and microfibers, and microspheres). 

Several researchers have investigated the mechanism and various basic principles involved in CO2 flooding. It has been r )orted that at the elevated pressure CO2 can recover additional oil which is not recoverable by conventional methods. In addition. Supper-critical CO2 develops multicontact miscibility with various crude oils, resulting in a very efficient oil displacement in porous media. Various efforts have been made by Holm and O Brien to reduce carbon dioxide channeling by reducing its mobility. 

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