A scale-up method to design and implement a cooling profile for unseeded batch cooling crystallization has been investigated. Due to the reduced heat transfer area to volumn ratio, temperature differnce between the reactor and jacket increases in a large crystallizer, which may induce unwanted nucleation on the crystallizer wall.

Addressing this problem, a method to design a cooling-holding profile that minimizes the undershoot of the jacket temperature has been proposed together with a fine batch control technique that can practice the profile as designed.

Experiments have been conducted for scaling-up the result with a 100 mL crystallizer to a 5 L system for crystalliation of polyhydroxybenzophenon. As a consequence, it has been observed that the proposed method correctly works as anticipated.