Carbon adsorbents are very commonly used for adsorption applications and their use dates back to 1600BC.  Carbons can be prepared  from a wide variety of sources including coal (anthracite or brown coal), lignite, wood, nut shall, polymers, and other biomass.  These materials are first pyrolyzed and carbonized to remove the volatile fraction and then activated by using gases such as steam at or above 800°C.  Alternative activation procedures using inorganic chemicals is also widely practiced leading to a different pore sizes.

In all of these activated carbon processes, a pore size distribution is produced.  Micropores, mesopores, and macropores are all produced to varying degrees and a vast amount of literature has sprung up on how to determine and characterize pore size distributions.  For gas storage applications, it is not always desirable to have a range in pore sizes - storage of gases (often methane or hydrogen) frequently requires the micropore size only and hence a uniform microporous carbon would be highly desirable.  In this project we are attempting to create microporous carbons for gas storage which contain a single size micropore of a well defined shape using inorganic templating methods.  Our application of the materials will be to hydrogen storage and to this end, a equilibrium test unit has been constructed allowing high pressure hydrogen adsorption to be measured.

For more information on this project, contact Yunxia Yang or Paul Webley.

 

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