The influence of humidity on the overall mass transfer coefficient of the Wheeler-Jonas equation

The Wheeler-Jonas model is well known for its good prediction of breakthrou gh times for organic vapors on activated carbon beds. However, it is valid only in dry conditions: no prewetting of the filter and no humidity in the ambient air during use. One of the parameters that is likely to be influenc ed is the overall mass transfer coefficient k(v). By measuring over 200 bre akthrough times, with 7 different vapors on 4 different types of activated carbon, a simple but satisfactory model for the influence of moisture on k( v) was established. The only items of information needed, compared with the application of the Wheeler-Jonas equation under dry circumstances, are the water isotherm and the total pore volume of the activated carbon.