Mesoporous carbonaceous solid

Sulfonated Starbon , A Mesoporous Carbonaceous Solid Acid... 

High porosity carbons ranging from typically microporous solids of narrow pore size distribution to materials with over 30% of mesopore contribution were produced by the treatment of various polymeric-type (coal) and carbonaceous (mesophase, semi-cokes, commercial active carbon) precursors with an excess of KOH. The effects related to parent material nature, KOH/precursor ratio and reaction temperature and time on the porosity characteristics and surface chemistry is described. The results are discussed in terms of suitability of produced carbons as an electrode material in electric double-layer capacitors. 

Presented are the examinations of the multifimctional mineral-earbon and zeolite-carbon sorbents prepared from kaolinite with an admixture of carbonaceous materials industrial waste deposits, municipal sewage sludge and cellulose. The mixture of raw materials was thermally and hydrothermally pretreated in order to facilitate their specific structure. The parameters of capillary structure (micro and mesopores) were determined. For examinations of porous structure the mereury porosimetry method was used. In order to evaluate the solid phase transformation during the each step of sorbent preparation the SEM observation with quantitative X-ray mieroanalysis were made. 

Carbonaceous compounds deposited on aluminosilicate mesoporous molecular sieves of the MCM-41 type during conversion of cyclohexene at various temperatures have been investigated using solid-state NMR and other techniques. 

Type 1 isotherms exhibit prominent adsorption at low relative pressures p/po (the relative pressure p/po is defined as the equilibrium v or pressure divided by the saturation vapor pressure) and then level off. Type 1 isotherm is usually considered to be indicative of adsorption in micropores (e.g., adsorption of benzene on microporous active carbon) or monolayer adsorption due to the stror adsorbent-adsorbate interactions (which may be the case for chemisorption, which involves chemical bonding between adsorbate and the adsorbent surface, e.g., adsorption of hydrogen on iron). In the case of nonpolar gases commonly used for charactmzation of porous solids (nitrogen, argon) [10, 12, 13, 17, 56], chemisorption is unlikely and therefore e I reflects usually adsorption on microporous solids. However, type I isotherms may also be observed for mesoporous materials with pore size close to the micropore range. In particular, in the case of adsorption of N2 at 77 K or Ar at both 77 K and 87 K in cylindrical pores, a type I isotherm would have to level off below the relative pressure of about 0.1 for the material to be exclusively microporous, as inferred fi-om tile results of recent studies of siliceous and carbonaceous ordered mesoporous materials (OMM) [57-59]. Consequently, when a type 1 isotherm does not level off below the relative... 

Various examples of solid-state NMR applications are collected in the final Section 4. This section is divided into 13 subsections depending on the type of the material studied (4.1) organic solids (4.2) inclusion compounds (4.3) amino acids and peptides (4.4) proteins (4.5) pharmaceutical and biomedical applications (4.6) polymers (4.7) carbonaceous materials (4.8) organometallic and coordination compounds (4.9) glasses and amorphous solids (4.10) micro- and mesoporous solids (4.11) surface science and catalysis, and (4.12) inorganic and other related solids. 

Mesostructured inorganic solids, originated from self-assembling of supramolec-ular structures, represent a class of suitable templates for the achievement of nanostructured materials. Ordered mesoporous polymers and carbonaceous frameworks... 

This paper deals with the principles, advantages and limitations of measurement of sorption equilibria under isosteric conditions. It further assesses the sorption-isosteric method (SIM) as an effective tool for providing complete sets of sorption-thermodynamic functions, viz., enthalpy, standard entropy and standard Gibbs free energy of sorption, for nanoporous solids, i.e., micro- and mesoporous ones, as functions of sorption-phase concentration, n, over its entire range, and to approach such data for mixtures. The usefulness of SIM is exemplified by sorption systems that comprise atmospheric gases on zeolites and carbon dioxide, CO2, on carbonaceous sorbents, as well as several of their mixtures. 

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