Using data in Exercise 15.17, estimate the effective diffusivity of  water vapor in the pores of activated alumina with the following  properties: ρ_p = 1.38 g/cm³, ϵ_p = 0:52, average d_p = 60 A , and tortuosity  = 2.3. Consider all mechanisms of diffusion except surface  diffusion.

Data From Exercise 15.17

Water vapor in an air stream is to be adsorbed in a 12.06-cm-i.d.  column packed with 3.3-mm-diameter Alcoa F-200 activatedalumina beads of external porosity of 0.442. At a location in the bed  where the pressure is 653.3 kPa, temperature is 21°C, gas flow rate  is 1.327 kg/minute, and dew-point temperature is 11.2°C, estimate the external, gas-to-particle mass-transfer and heat-transfer coefficients.