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Dynamic control structures are significant for liquid–liquid extraction combined with heterogeneous azeotropic distillation (LEHAD) and liquid–liquid extraction combined with extractive distillation (LEED) processes, which were proposed in our previous work for the separation of the azeotrope of propylene glycol methyl ether and water. However, there may be complications regarding the dynamic controllability of the two hybrid processes, and this work investigates the dynamic control structures. For the LEHAD process, an improved composition–temperature cascade control structure using the ratio of the reboiler duty to feed flow (QR/F) can realize effective control when feed disturbances are added. For the LEED process, the improved dual temperature control structure with QR/F was able to handle the disturbances well. Moreover, a comparison between the two hybrid processes was made according to the dynamic controllability, and the integral of the squared errors was calculated. The results show that the LEHA...