Dynamic model for dehydration process of industrial purified terephthalic acid solvent is investigated to understand and characterize the process. A temperature differential expression is presented, which ensures the equation to convergence and short computation time. The model is used to study the dynamic behavior of an azeotropic distillation column separating acetic acid and water using n-butyl acetate as the entrainer. Responses of the column to feed flow and aqueous reflux flow are simulated. The movement of temperature front is also simulated. The comparison between simulation and industrial values shows that the model and algorithm are effective. On the basis of simulation and analysis, control strategy, online optimization and so on can be implemented effectively in dehydration process of purified terephthalic acid solvent.