Commensurate adsorption

D channel of the framework is composed of oval-shaped cages of diameter 5.1 A, connected by small necks with a diameter of 3.2 A each of the cages is 7.3 A in length along the channel. Such pore characteristics offer unique adsorption behavior for the framework, with exclusion of all branched hydrocarbons and any paraffin or olefins longer than C4. The cage effect leads to commensurate adsorption for smaller molecules such as propane and... 

Incommensurate adsorption, or as the name suggests, non-commensurate adsorption, happens when there are size or symmetry mismatches between the adsorbate and the pores of the adsorbent. The phenomenon was first observed and quantified for the surface adsorption of organic molecules on layered substrates, with an incommensurate-commensurate transition occurring as a function of physical parameters such as temperature and pressure. ... 

A transition to incommensurate adsorption is often observed in MMOFs that exhibit commensurate adsorption. A classic example is the aforementioned... 

While addressing hydrocarbon sorption properties of MOFs, there has been intense debate on the commensurate adsorption of hydrocarbons using MOFs the mean munber of adsorbed hydrocarbon molecules relates to the symmetry of the framework topology, which is nearly impossible in routinely studied/used zeolites [109]. Jing Li et al. reported that adsorption capacity and location of molecules are specifically controlled by cavity size, shape, symmetry, and channel features such as chaimel segment [109]. Three different adsorption mechanisms have been offered for the sorption and separation of hydrocarbons (1) equilibrium (2) steric, and (3) kinetic. In some complex materials, it is possible that one or more mechanisms m operate at the same time. The equilibrium sorption and separation mechanism relies on... 

USE OF SORBENT MATERIALS IN OIL SPILL RESPONSE Technical Report from The International Tanker Owners Pollution Federation Limited (TTOPF) (2013). Wu, H. H., Gong, Q. H., Olson, D. H., and Li, J. Commensurate adsorption of hydrocarbons and alcohols in microporous metal organic frameworks. Chem Rev 112, 836- 868(2012). 

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