Inorganic gases, adsorption

Pitak, O. Gas chromatography of inorganic fluorine compounds (1). III. Investigation of the separation of corrosive inorganic volatile fluorine compounds by means of gas adsorption chromatography. Chromatographia 3, 29 (1970). 

M. Kruk and M. Jaroniec, Gas Adsorption Characterization of Ordered Organic-inorganic Nanocomposite Materials. Chem. Mater., 2001, 13, 3169-3183. 

In a series of papers, Ma and his co-workers [1 ] systematically examined the interrelationship between adsorption, permeation and diffusion in microporous silica membranes. Both equilibrium and nonequilibrium properties of the microporous inorganic gas separation membranes were studied. Both high pressure and low pressure gravimetric units were used in their adsorption measurements. 

Chemical and morphological characteristics of inorganic sorbents with respect to gas adsorption... 

Pore size and pore size distribution. Particularly two methods have been used to determine the pore size in adsorbing materials of both organic and inorganic nature, namely, the gas adsorption technique and the mercury intrusion porosimetry. On the basis of information provided by these methods, a number of serious conclusions have been drawn on the porous structure of macroporous styrene-DVB copolymers. This necessitates a more critical analysis of the possible errors in the interpretation of the results of measuring adsorption isotherms and mercury intrusion. 

Onishi S., Ohmori T., Ohkubo T., Noguchi H., Li D., Hanzawa Y., Kanoh H. and Kaneko K., Hydrogen-bond change-associated gas adsorption in inorganic-organic hybrid microporous crystals. Appl. Surf. Sci. 196 (2002)... 

PSM now routinely allows for the synthesis of MOFs that cannot be made by other routes, either because the functional groups are not tolerant of the synthetic conditions (covalent and dative PSM) or because direct synthesis leads to other phases (covalent and inorganic PSM). Furthermore, modified materials have been demonstrated to possess enhanced gas adsorption capacities and selectivities, and higher catalytic activity than their unmodified counterparts. 

Over the past fifty years, the gas adsorption has become the main technique for the characterization of porous or finely divided solids. This rise is due to the success of the BET and B3H theories (and related procedures), as well as to the growing needs of characterization data for the inorganic, organic and pharmaceutical industries or research centers. Other needs concern crude measurements of adsorbed amounts (chemisorption, gas separation data). Consequently, many laboratories now buy commercially available devices, or build them, to perform these measurements. The development of the computer science has also provided facilities for the automation of the entire experimental run and data reduction. 

During the last seven years, MOF membranes have been developed and tested for gas separation. There is, so far, no major industrial gas separation that is using inorganic membranes. MOF membranes are promising candidates for the shape-selective separation of a gas mixture by molecular sieving. In addition to molecular sieving based on molecular exclusion, MOF membrane can separate a gas mixture by the interplay of mixed gas adsorption and diffusion. MOF manbranes show the effect of framework flexibility, which facilitates module constructiou but prohibits a sharp cut-off [177]. An application of MMMs, which consist of MOF nanoparticles in a standard polymer, in industrial gas separation is predicted for the near future. 

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