Indirect CO2 mineral sequestration that involves two separate steps,with acetic acid as the recycling medium,was limited by a crystallization conversion of only 20% in the second gas-liquid reactive crystallization st...Indirect CO2 mineral sequestration that involves two separate steps,with acetic acid as the recycling medium,was limited by a crystallization conversion of only 20% in the second gas-liquid reactive crystallization step.In this paper,the second carbonation step was greatly improved by coupling reactive crystallization and solvent extraction with the introduction of an organic solvent,tributyl phosphate(TBP),to the process.The effect of the initial concentration of calcium acetate in the aqueous solution on the crystallization conversion was studied experimentally.The obtained calcium conversion was above 40%,which was one time higher than that reported in the literature.Based on the mechanism discussion and thermodynamic equilibrium calculation analysis,it can be concluded that adding TBP to the step can consume the produced acetic acid,and it is in favor of the precipitation of calcium carbonate.While the challenge presented by the strong interaction between calcium ions and acetate ions for further improving crystallization conversion cannot be solved only by the addition of TBP.展开更多
Crystallization is one of the oldest separation and purification unit operations, and has recently contributed to significant improvements in producing higher-value products with specific properties and in building ef...Crystallization is one of the oldest separation and purification unit operations, and has recently contributed to significant improvements in producing higher-value products with specific properties and in building efficient manufacturing processes. In this paper, we review recent developments in crystal engineering and crystallization process design and control in the pharmaceutical industry. We systematically summarize recent methods for understanding and developing new types of crystals such as co-crystals, polymorphs, and solvates, and include several milestones such as the launch of the first co-crystal drug, Entresto （No- vartis）, and the continuous manufacture of Orkambi （Vertex）. Conventional batch and continuous processes, which are becoming increasingly mature, are being coupled with various control strategies and the recently developed crystallizers are thus adapting to the needs of the pharmaceutical industry. The development of crystallization process design and control has led to the appearance of several new and innovative crystal- lizer geometries for continuous operation and improved performance. This paper also reviews major recent orogress in the area of process analytical technology.展开更多
4A Zeolite has been prepared from Kaolin under low-temperature hydrothermal conditions. The analysis results on the concentration changes of NaOH, SiO2 and Al2O3 in liquid phases as well as the texture, morphology and...4A Zeolite has been prepared from Kaolin under low-temperature hydrothermal conditions. The analysis results on the concentration changes of NaOH, SiO2 and Al2O3 in liquid phases as well as the texture, morphology and structure changes of solid phases show that the crystallization process of 4A zeolite roughly comprises three periods: induction of crystal nucleus, crystal growth and steady state transformation.展开更多
文摘Indirect CO2 mineral sequestration that involves two separate steps,with acetic acid as the recycling medium,was limited by a crystallization conversion of only 20% in the second gas-liquid reactive crystallization step.In this paper,the second carbonation step was greatly improved by coupling reactive crystallization and solvent extraction with the introduction of an organic solvent,tributyl phosphate(TBP),to the process.The effect of the initial concentration of calcium acetate in the aqueous solution on the crystallization conversion was studied experimentally.The obtained calcium conversion was above 40%,which was one time higher than that reported in the literature.Based on the mechanism discussion and thermodynamic equilibrium calculation analysis,it can be concluded that adding TBP to the step can consume the produced acetic acid,and it is in favor of the precipitation of calcium carbonate.While the challenge presented by the strong interaction between calcium ions and acetate ions for further improving crystallization conversion cannot be solved only by the addition of TBP.
文摘Crystallization is one of the oldest separation and purification unit operations, and has recently contributed to significant improvements in producing higher-value products with specific properties and in building efficient manufacturing processes. In this paper, we review recent developments in crystal engineering and crystallization process design and control in the pharmaceutical industry. We systematically summarize recent methods for understanding and developing new types of crystals such as co-crystals, polymorphs, and solvates, and include several milestones such as the launch of the first co-crystal drug, Entresto （No- vartis）, and the continuous manufacture of Orkambi （Vertex）. Conventional batch and continuous processes, which are becoming increasingly mature, are being coupled with various control strategies and the recently developed crystallizers are thus adapting to the needs of the pharmaceutical industry. The development of crystallization process design and control has led to the appearance of several new and innovative crystal- lizer geometries for continuous operation and improved performance. This paper also reviews major recent orogress in the area of process analytical technology.
文摘4A Zeolite has been prepared from Kaolin under low-temperature hydrothermal conditions. The analysis results on the concentration changes of NaOH, SiO2 and Al2O3 in liquid phases as well as the texture, morphology and structure changes of solid phases show that the crystallization process of 4A zeolite roughly comprises three periods: induction of crystal nucleus, crystal growth and steady state transformation.
