A study of dynamic adsorption characteristics of chlorinated organic solvents onto the activated carbon particles: Chloroform and/or 1,2-dichloropropane-activated carbon systems

To elucidate the kinetic characteristics or the adsorption of organic solvents dissolved in water onto a solid adsorbent, the authors proposed an elaborated experimental scheme where the adsorptive components can be batchwisely taken up from the aqueous medium, being well stirred in a vessel without dead space. The present study deals with chloroform (CH)-water and/or 1,2-dichloropropane (DCP)-water systems. It can be concluded from the observed isotherms that DCP can adsorb more strongly than the other over the whole concentration range examined. On the basis of the measured transient concentration decay curves and the mathematically simulated ones for single component systems, it can be concluded that the predominant mass transfer resistance would be confined within the solid phase, and the simulated effective diffusion coefficients for CH and DCP increased linearly with an increasing adsorption amount for each component, which does not contradict the previous results of other investigators. To predict the adsorption amount of each component in a binary mixture system, the authors employed a widely acknowledged Ideal Adsorbed Solution Model (IAS) and concluded that the model is successfully applicable to the present mixture system. Some transient decay curves were also measured for the binary systems. Incorporating the IAS model into the mass transfer governing equations, the authors simulated the observed decay curves in terms of the effective diffusion coefficients. As a result, the coefficient of DCP for the binary system is compatible with that for the single component system, while the coefficient for CH is larger than that for the single component system.