Mass transport dynamics of N2 and O2 in wood-based carbon molecular sieves affected by pre-treatments and comminution

Carbon honeycomb adsorbents having molecular sieve characteristics were prepared by controlled single-step carbonization from 1 × 1 × 1 cm3 cubes of spruce wood. The carbonized xylem retained the original tracheal structure of the wood. The obtained three-dimensional frame exhibits low transport diffusional resistance due to the wide straight micron sized channels. The wood-based carbon molecular sieve (CMS) samples, synthesized in various ways, were characterized by their dynamic adsorption properties using the unique potentials of the frequency-response (FR) technique. The carbon honeycomb cubes exhibited significantly lower macropore diffusional resistance and higher kinetic selectivity in N2 and O2 separation than that of a commercial pelletized adsorbent (Takeda MSC-4A).