Separation and purification of stigmasterol and β-sitosterol from phytosterol mixtures by solvent crystallization method

2005 ◽  
Vol 41 (2) ◽  
pp. 173-178 ◽  
Author(s):  
Wen Lin Xu ◽  
Yi Bo Huang ◽  
Jun Hong Qian ◽  
Ou Sha ◽  
Ya Qiong Wang
Keyword(s):  
Separation And Purification ◽  
Solvent Crystallization ◽  
Crystallization Method

scholarly journals A Hybrid Framework for Simultaneous Process and Solvent Optimization of Continuous Anti-Solvent Crystallization with Distillation for Solvent Recycling

Processes ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 63
Author(s):  
Jiayuan Wang ◽  
Lingyu Zhu ◽  
Richard Lakerveld
Keyword(s):  
Nonlinear Programming ◽  
Continuous Process ◽  
Continuous Mapping ◽  
Mapping Method ◽  
Mixed Integer ◽  
Separation And Purification ◽  
Solvent Selection ◽  
Integer Variables ◽  
Solvent Crystallization ◽  
Minlp Problem

Anti-solvent crystallization is frequently applied in pharmaceutical processes for the separation and purification of intermediate compounds and active ingredients. The selection of optimal solvent types is important to improve the economic performance and sustainability of the process, but is challenged by the discrete nature and large number of possible solvent combinations and the inherent relations between solvent selection and optimal process design. A computational framework is presented for the simultaneous solvent selection and optimization for a continuous process involving crystallization and distillation for recycling of the anti-solvent. The method is based on the perturbed-chain statistical associated fluid theory (PC-SAFT) equation of state to predict relevant thermodynamic properties of mixtures within the process. Alternative process configurations were represented by a superstructure. Due to the high nonlinearity of the thermodynamic models and rigorous models for distillation, the resulting mixed-integer nonlinear programming (MINLP) problem is difficult to solve by state-of-the-art solvers. Therefore, a continuous mapping method was adopted to relax the integer variables related to solvent selection, which makes the scale of the problem formulation independent of the number of solvents under consideration. Furthermore, a genetic algorithm was used to optimize the integer variables related to the superstructure. The hybrid stochastic and deterministic optimization framework converts the original MINLP problem into a nonlinear programming (NLP) problem, which is computationally more tractable. The successful application of the proposed method was demonstrated by a case study on the continuous anti-solvent crystallization of paracetamol.

Crystallization of barium hexaferrite

1992 ◽  
Vol 50 (1) ◽  
pp. 362-363
Author(s):  
Chung-kook Lee ◽  
Yolande Berta ◽  
Robert F. Speyer
Keyword(s):  
Size Distribution ◽  
Raw Materials ◽  
Barium Hexaferrite ◽  
Recording Media ◽  
Magnetic Recording Media ◽  
Promising Candidate ◽  
Crystallization Method ◽  
Temperature Heat ◽  
High Density Magnetic Recording ◽  
Temperature Heat Treatment

Barium hexaferrite (BaFe12O19) is a promising candidate for high density magnetic recording media due to its superior magnetic properties. For particulate recording media, nano-sized single crystalline powders with a narrow size distribution are a primary application requirement. The glass-crystallization method is preferred because of the controllability of crystallization kinetics, hence, particle size and size distribution. A disadvantage of this method is the need to melt raw materials at high temperatures with non-reactive crucibles, e.g. platinum. However, in this work, we have shown that crystal growth of barium hexaferrite occurred during low temperature heat treatment of raw batches.

A Review of the Bioactive Ingredients, Pharmacological Functions and Mechanisms of Inonotus obliquus

2020 ◽  
Vol 17 ◽  
Author(s):  
Gulinigaer Anwaier ◽  
Cong Wen ◽  
Yi-ni Caoili ◽  
Rong Qi
Keyword(s):  
Digestive System ◽  
Treatment Strategies ◽  
Research Progress ◽  
Chemical Components ◽  
Separation And Purification ◽  
Active Components ◽  
Inonotus Obliquus ◽  
Global Issues ◽  
Medicinal Fungus ◽  
Digestive System Diseases

: As a medicinal fungus, Inonotus obliquus (IO) has been widely used in the treatment of cancer and digestive system diseases. Despite the progress that has been made in the studies of IO and its active compounds, their applications in other important clinical diseases, such as cardiovascular diseases, which are major global issues with limited treatment strategies, are seldom reported. This review summarizes the separation and purification methods of chemical components of IO, the advances in their applications, and research progress on the pharmacological effects and related mechanisms of IO in disease prevention. This review will help researchers and clinicians to further understand the pharmacological functions and mechanisms of IO and its active components, which may extend their medical applications in the prevention and treatment of other diseases in addition to tumors and digestive system diseases in the near future.

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