A nonequilibrium model for three-phase distillation in packed columns is formulated. The model takes into account the mass and heat transfer between all three existing phases. Because of a lack of methods for the determination of the needed values for mass-transfer coefficients and interfacial areas concerning three-phase situations, it is assumed that on every interfacial area only two of the three phases are in contact. Therefore, the well-known methods for the mass-transfer coefficients are applied. The comparison of the experimental results shows the good performance of the developed nonequilibrium model. Finally, undesired phase separation in the reboiler and resulting peaks in the column pressure are discussed.