Operation Design of Reaction Crystallization Using Homogeneity Evaluation for the Quality Improvement of Agglomerated Crystalline Particles

Abstract

In the quality control of crystalline particles, the uniformity of the distribution of each characteristic, such as size and shape, is important. In particular, the problem in reaction crystallization is that the comprehensive uniformity of characteristic distributions is frequently reduced by the agglomeration phenomena. In this study, we designed an operation method to improve the comprehensive uniformity in a liquid–liquid reaction crystallization by evaluating the dynamic variation in the uniformity of particle size and crystal shape using homogeneity. The homogeneity of final particles increased when the supersaturation was lowered by intermittent operation with inner seed production. Since the ratios of the uniformities of particle sizes and crystal shapes constituting homogeneity varied dynamically, the intermittent operation was designed by focusing on individual uniformities. The uniformity of particle size for the final particles was increased via modulation operation using reverse addition for the dissolution of the microparticles. In the growth stage after the reverse addition, the uniformity of the shape of the final particles was increased by raising the number of times of adding solution for decreasing the supersaturation. In addition, we proposed suitable addition methods to improve comprehensive uniformity by controlling uniformity constituting homogeneity at each stage of intermittent operation.

Mathematical Modeling of Changes in the Dispersed Composition of Solid Phase Particles in Technological Apparatuses of Periodic and Continuous Action

“…Bitumen BDU 60/90 was used as a binder. The average particle diameter in the initial product was 120 microns with a density of 1.26 g/cm 3 . The experiments were carried out at different speeds of rotation.…”

“…Many chemical-technological processes involving the solid phase entail a change in the size of the dispersed particles. These include the processes of crystallization, dissolution, drying, combustion, pyrolysis, gasification, abrasion, and a number of others [1][2][3][4][5][6][7]. A change in the dispersed composition of the solid phase during the process can affect it via several mechanisms such as the kinetics of the process, a decrease or increase in the specific interfacial surface area, or a change in the nature of the movement of phases in the working volume.…”

Operation Design of Co-Crystallization Using Homogeneity Evaluation Including “Single Component Excess” Index

“…e particle sizes and crystal shapes of 300 individual particles were measured in each experiment. e uniformity of the distribution of the particle size (P L ) and crystal shape (P S ) was estimated using a previous study (Ohyama et al, 2021). P L was estimated by using the quantity-based coe cient of variation (CV) of the particle size distribution.…”

“…In our previous study, we developed an operation method for improving the comprehensive uniformity of crystalline particles during reaction crystallization using homogeneity. However, the study was limited to homogeneity based on external characteristics, such as particle size and crystal shape, without considering component characteristics such as purity (Ohyama et al, 2021). Since crystallization involves both the production of crystalline particles and their puri cation, the evaluation of component characteristics is essential (Horosanskaia et al, 2019).…”

Effect of Operating Conditions on the Characteristics of Crystalline Particles in a Cascade-Type Crystallizer

“…Crystallization is widely used as separation and purification processes in various industrial fields. − In the pharmaceutical industry, more than 90% of all APIs are crystals of small organic molecules. , Therefore, crystallization is important as a unit operation to maintain the required quality of final products. In addition, the characteristics of crystalline particles strongly affect the efficiency of downstream process, purity of final products, and performance of the material. − For this reason, it is important to control the characteristics of crystalline particles based on crystallization.…”