Chemical activation narrow micropore size distributions

Thermogravimetry/mass spectrometry was used to determine adsorptive capacity of several commercially available activated carbons produced from coal, coconut, and petroleum pitch precursors. The range of their N2 BET surface areas was between 400 to 2000 m /g. Although, carbons with high adsorption capacity contained similar C, N, and O contents, proximate analyses, surface areas and micropore volumes, no significant correlations were found between chemical and physical properties and the NO, adsorptive capacity. One possibly important characteristic of the carbons correlated with NO, adsorption capacity was specific and narrow pore size distribution with an effective pore diameter of 0.56 nm. 

The main limitation of using microporous zeolites in catalysis is their small pore size which faces difficulty in offering catalytic activity to large molecules. That is why, the mesoporous zeolitic materials emerge as alternative materials the development of the mesoporous silicas has experienced an impressive progress since the discovery of MCM-41 by scientists of Mobil Corporation in 1992 [17]. Their well-defined surface chemical properties, high surface areas, and narrow pore-size distributions make them interesting and efficient catalysts for the transformation of bulky substrates [18]. 

This process was developed by a division of Nobel Industries, a major chemical corporation in Sweden. The heart of the process is a unique adsorbent called Bonopore 110, which is described as a microporous, crosslinked polymer in the form of spherical particles with a narrow size distribution (Heinegard, 1988). The particles have a pore diameter of approximately 80 A, a. specific surface area of about 800 sq m per gram, and a diameter of about 0.5 mm. Adsorption isotherms for four typical organic compounds and Bonopore 110 are given in Figure 12-48. The polymer adsorbent is claimed to have the following advantages over activated carbon ... 

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