Intraparticle mass transport in liquid‐filled pores

Adsorption rate data were measured at 25° to 75°C for benzaldehyde on polymeric, porous Amberlite particles. When the benzaldehyde is dissolved in methanol, the adsorption capacity is very low. Data for methanol solutions gave reasonable values for intraparticle diffusivities based solely on transport in the pore volume. For adsorption from aqueous solution (where the adsorption capacity was high), the contribution of surface diffusion was important. From the two sets of data it was possible to evaluate average effective surface diffusivities by using a model based upon both pore‐volume and surface transport. These values were about 10 −8 cm 2 /s and were sufficiently sensitive to temperature to give activation energies of 7 to 9 k cal/mole. For the more hydrophobic Amberlite, XAD‐4, surface transport was many times as large as pore‐volume diffusion.