ADSORPTION-DESORPTION PROPERTIES OF SORBENTS
Abstract:
Equilibrium adsorption data is reported for activated carbons of interest as chemical agent sorbents. Measurements were made with nitrogen at low temperature and with dimethyl methylphosphonate, DMMP, at 25 and 42C. The sorbents studied include activated carbon fibers made from Fortisan and viscose rayon, some highly activated coconut shell charcoal, and a coal-base carbon. The nitrogen data was combined with mercury porosimeter measurements to give the total pore volume distributions from 10 to 100,000A radius. Both carbon fibers show a greater proportion of volume in pores less than 10A than the other carbons. Isosteric heats of adsorption of DMMP on the carbon fibers and the coal-base carbon are reported. It is suggested that the hysteresis in the DMMP systems is the result of the superposition of two phenomena, one the type seen in nitrogen adsorption entailing loop closure and the other an effect extending to lower pressures. Results of some desorption measurements with DMMP are discussed.