Purified terephthalic acid (PTA) is critical to the development of the polyester industry. PTA productionconsists of p-xylene oxidation reaction and crude terephthalic acid (CTA) hydropurification. The hydropurificationprocess is necessary to eliminate 4-carboxybenzaldehyde (4-CBA), which is a harmful byproduct of the oxidation reactionprocess. Based on the dynamic model of the hydropurification process, two control systems are studied usingAspen Dynamics. The first system is the ratio control system, in which the mass flows of CTA and deionized water arecontrolled. The second system is the multivariable predictive control-proportional-integral-derivative cascade controlstrategy, in which the concentrations of 4-CBA and carbon monoxide are chosen as control variables and the reactiontemperature and hydrogen flow are selected as manipulated variables. A detailed dynamic behavior is investigatedthrough simulation. Results show that the developed control strategies exhibit good control performances, thereby providingtheoretical guidance for advanced control of industry-scale PTA production.