Crystallization of Cephradine Polymorphs and Hydrates from Mixed Solvents of Methanol and Water

Abstract

Cephradine monohydrate (CPH) crystallizes with a needle-like shape which leads to severe agglomeration and slow filtration. Effects of different operating conditions on the particle size and shape as well as the filterability of the crystal products are described. The solubility and stability of one anhydrate of cephradine (CPA1) and CPH as a function of temperature and water activity was investigated in different methanol and water mixtures. A solvent-mediated transformation from CPH to CPA1 was observed at water mole fractions below 0.2-0.35 depending on the temperature. The crystallization behavior of CPH was studied by linear cooling and antisolvent crystallization. Lowering the cooling rate and addition of seeds led to an increase in particle size and improvement of filterability.

Thermodynamic Modeling the Solid–Liquid Phase Equilibrium of a Water–Methanol–Potassium Dihydrogen Phosphate Ternary System with a Mixed-Solvent Electrolyte (MSE) Model

“…Galvão et al used methanol as an antisolvent to determine the solubility of NaCl, KCl, and NH 4 Cl in the methanol–water system. A variety of other products can be obtained by using methanol as an antisolvent in crystallization, e.g., l -histidine, , l -ornithine- l -aspartate, cephradine, and glycine . In order to solve the problems existing in the traditional MKP production process, methanol was selected as an antisolvent to replace the traditional crystallization process in this paper.…”

Preparation, Characterization, and Desolvation of 5‐Sulfoisophthalic Acid Sodium Salt Solvates

“…Every solvent or additive with various physicochemical properties can not only affect the crystal growth process but has a crucial impact on crystal stability [1][2][3][4][5]. Various crystal forms such as amorphous substances, co-crystals, polymorphs, and solvates can be generated from the crystallization process [6][7][8][9][10]. The amorphous form has an irregular internal molecular arrangement, poor stability, and is prone to crystal transformation [11].…”