Langmuir, Vol.18, No.11, 4300-4306, 2002
Adsorption and reaction of diethyl sulfide on active carbons with and without impregnants under static conditions
Active carbons of different grades with and without impregnants were studied for the adsorption of diethyl sulfide (DES), the simulant of sulfur mustard, under static conditions at 36 +/- 1 degreesC. Kinetics of the adsorption were studied using linear driving force (LDF) and the Fickian diffusion model. The kinetic parameters such as equilibration time, equilibration capacity, equilibration constant, diffusional exponent, and adsorbate-adsorbent interaction constant (K) were determined. The diffusional exponent (n), being less than 0.5, indicated a Fickian mode of diffusion of DES in the studied carbon. Chemical interaction also seemed to be the second mechanism (although minor) involved in the DES uptake rate (the first being simple Fickian diffusion). The adsorbate-adsorbent interaction constant did not vary significantly indicating that probably DES chemically interacts to a small extent with the metal salts present on the surface of active carbon as impregnants. However, the characterization of reaction products, after extraction in dichloromethane, using GUMS indicated that the system CrO3/NaOH/carbon (carbon impregnated with Cr(VI) plus NaOH) only reacted with DES to give diethyl sulfone.