Production of crystalline particles with high homogeneity in reaction crystallization by using pH-solubility-profile

[Display omitted] •The new evaluation method of uniformity of quality of crystals was proposed.•The operation method of improvement of uniformity was developed.•The solution pH was an important factor and also affects the quality of crystals. The quality of crystalline particles is determined by many kinds of characteristics. Therefore, it is necessary to evaluate each characteristic comprehensively. In this study, the uniformity of each characteristic of the crystalline particles was defined and proposed as performance index “homogeneity”, and the operation method of reaction crystallization for improvement the crystal qualities was developed. Homogeneity was evaluated by using the uniformity of particle size and crystal shape. Furthermore, in order to produce the crystalline particles with high homogeneity, it was necessary to consider the effects of solution pH and the mixing methods of two solutions.