This review discusses important research developments and arising challenges in the field of industrial crystallization with an emphasis on recent problems. The most relevant areas of research have been identified. Th...This review discusses important research developments and arising challenges in the field of industrial crystallization with an emphasis on recent problems. The most relevant areas of research have been identified. These are the prediction of phase diagrams; the prediction of effects of impurities and additives; the design of fluid dynamics; the process control with process analytical technologies （PAT） tools; the polymorph and solvate screening; the stabilization of non-stable phases; and the product design. The potential of industrial crystallization in various areas is outlined and discussed with particular reference to the product quality, process design, and control. On this basis, possible future directions for research and development have been pointed out to highlight the importance of crystallization as an outstanding technique for separation, purification as well as for product design.展开更多
The metastable state and nucleation kinetics of clindamycin phosphate (CP) in cooling crystallization were studied by metastable zone width (MZW) method and induction time method. By correlating the MZW experimental r...The metastable state and nucleation kinetics of clindamycin phosphate (CP) in cooling crystallization were studied by metastable zone width (MZW) method and induction time method. By correlating the MZW experimental results with temperature, agitation rate and cooling rate, it is found that the correlation result shows good agreement with the change trend of MZW. The critical nucleation parameters were evaluated based on the classical theory of nucleation; both the interfacial tension and the radius of critical nucleus increased with the decrease of relative supersaturation. The effect of supersaturation on the nucleation rate was analyzed. It is indicated that the new phase formation of CP is governed by mononuclear mechanism.展开更多
Mefenamic acid (MA) is a high-dose, anti-inflammatory, analgesic agent that is widely prescribed for pain related to menstrual disorders. It has some negative properties, such as a high hydrophobicity with a propensit...Mefenamic acid (MA) is a high-dose, anti-inflammatory, analgesic agent that is widely prescribed for pain related to menstrual disorders. It has some negative properties, such as a high hydrophobicity with a propensity to stick to surfaces, and possess great problems during granulation and tableting. Crystallization kinetics was investigated for mefenamic acid. Availability of data on the kinetics of crystal growth is very important for the development and operation of industrial crystallisation processes. The experiments for the measurement of crystal growth kinetics were carried out using the desupersaturation curve technique based on the measurement of the solution concentration versus time in a seeded isothermal batch experiment. To predict the optimum parameters (b, kb, g, kg) for the nucleation and growth kinetics from the desupersaturation curve obtained, the Population Balance Modelling was used and solved by the method of moments. The initial values for the optimisation problem were estimated by using the approach developed by Garside et al. (1982) [1].展开更多
Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystall...Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystallization behavior of the product.The particle size distribution,crystal phase,morphology,and surface area of magnesium hydroxide were characterized by Malvern laser particle size analyzer,X-ray diffraction(XRD),scanning electron microscope(SEM)and Branauer-Emmett-Teller(BET)method,respectively.The purity of products was analyzed by the chemical method.The effects of synthesis conditions on the particle size distribution and water content(filtration cake)of magnesium hydroxide were investigated.The results indicated that feeding mode and rate,and reaction temperature had important effects on water content and the particle size distribution of the product,and sodium chloride improved the crystallization behavior of magnesium hydroxide.The ball-like magne-sium hydroxides with the particle size distribution of 6.0–30.0μm and purity higher than 99.0%were obtained.This simple and mild synthesis method was promising to be scaled up for the industrial production of magnesium hydroxide.展开更多
文摘This review discusses important research developments and arising challenges in the field of industrial crystallization with an emphasis on recent problems. The most relevant areas of research have been identified. These are the prediction of phase diagrams; the prediction of effects of impurities and additives; the design of fluid dynamics; the process control with process analytical technologies （PAT） tools; the polymorph and solvate screening; the stabilization of non-stable phases; and the product design. The potential of industrial crystallization in various areas is outlined and discussed with particular reference to the product quality, process design, and control. On this basis, possible future directions for research and development have been pointed out to highlight the importance of crystallization as an outstanding technique for separation, purification as well as for product design.
基金Supported by the Program of Introducing Talents of Discipline to Universities (No. B06006)
文摘The metastable state and nucleation kinetics of clindamycin phosphate (CP) in cooling crystallization were studied by metastable zone width (MZW) method and induction time method. By correlating the MZW experimental results with temperature, agitation rate and cooling rate, it is found that the correlation result shows good agreement with the change trend of MZW. The critical nucleation parameters were evaluated based on the classical theory of nucleation; both the interfacial tension and the radius of critical nucleus increased with the decrease of relative supersaturation. The effect of supersaturation on the nucleation rate was analyzed. It is indicated that the new phase formation of CP is governed by mononuclear mechanism.
文摘Mefenamic acid (MA) is a high-dose, anti-inflammatory, analgesic agent that is widely prescribed for pain related to menstrual disorders. It has some negative properties, such as a high hydrophobicity with a propensity to stick to surfaces, and possess great problems during granulation and tableting. Crystallization kinetics was investigated for mefenamic acid. Availability of data on the kinetics of crystal growth is very important for the development and operation of industrial crystallisation processes. The experiments for the measurement of crystal growth kinetics were carried out using the desupersaturation curve technique based on the measurement of the solution concentration versus time in a seeded isothermal batch experiment. To predict the optimum parameters (b, kb, g, kg) for the nucleation and growth kinetics from the desupersaturation curve obtained, the Population Balance Modelling was used and solved by the method of moments. The initial values for the optimisation problem were estimated by using the approach developed by Garside et al. (1982) [1].
基金supported by the Shanghai Natural Science Foundation(No.09ZR147900)the Program for New Century Excellent Talents in University(NCET-08-0776).
文摘Magnesium hydroxide with high purity and uniform particle size distribution was synthesized by the direct precipitation method using MgCl_(2) and NaOH as reactive materials and NaCl as additive to improve the crystallization behavior of the product.The particle size distribution,crystal phase,morphology,and surface area of magnesium hydroxide were characterized by Malvern laser particle size analyzer,X-ray diffraction(XRD),scanning electron microscope(SEM)and Branauer-Emmett-Teller(BET)method,respectively.The purity of products was analyzed by the chemical method.The effects of synthesis conditions on the particle size distribution and water content(filtration cake)of magnesium hydroxide were investigated.The results indicated that feeding mode and rate,and reaction temperature had important effects on water content and the particle size distribution of the product,and sodium chloride improved the crystallization behavior of magnesium hydroxide.The ball-like magne-sium hydroxides with the particle size distribution of 6.0–30.0μm and purity higher than 99.0%were obtained.This simple and mild synthesis method was promising to be scaled up for the industrial production of magnesium hydroxide.
