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Additives effects on crystallization and morphology in a novel caustic aluminate solution decomposition

Ying ZHANG, Shili ZHENG, Yifei ZHANG, Hongbin XU, Yi ZHANG

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 88-92 doi: 10.1007/s11705-009-0133-5

摘要： A novel process of caustic aluminate solution decomposition by alcohol medium was developed by the Institute of Process Engineering, Chinese Academy of Sciences in order to solve the problem of low decomposition ratio in the traditional Bayer seeded hydrolysis process. In this research, effects of additives on the crystallization ratio, secondary particle size and morphology of aluminum hydroxide in the new process were studied to obtain high-quality products. On the basis of primary selection of additives, an orthogonal design L9(3 ) was used as a chemometric method to investigate the effects of additives. The studied parameters include the reaction style, quantity of additives, caustic soda concentration, as well as the combination manner. The crystallization ratios of sodium aluminate solution and crystal size of aluminum hydroxide, determined by ICP-OES, SEM and MLPSA (Malvern Laser Particle Size Analyzer), were used to evaluate the effects of the additives. The results showed that different combination manners could promote agglomeration or dispersion. An additive composed by Tween 80 and PEG 200 could promote agglomeration, while a spot of PEG species had a relatively strong dispersion effect. However, the additives had little effects on the crystallization ratios. According to the Raman spectra result, the added alcohol medium might serve as a kind of solvent.

关键词： additive     crystallization     morphology     caustic aluminate solution     aluminium hydroxide    

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The feasibility of coating by cooling crystallization on ibuprofen naked tablets

Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 211-219 doi: 10.1007/s11705-017-1619-1

摘要： Sugar spray coating is a frequently used process in the pharmaceutical industry. However, this process presents the disadvantage to form an amorphous coating around the active ingredient. A crystalline coating formed on the surface of a tablet is highly desirable. Recently, a new process of coating by cooling crystallization has been developed and applied on bisacodyl pastilles obtained by melt crystallization. In this work, we investigated the feasibility of coating by cooling crystallization on ibuprofen “naked tablets” manufactured by compression. In the first part of this work, the solubility and the metastable zone width have been determined experimentally for the coating solution because they are essential factors for any crystallization process. In the second part, the coating process is investigated on the operating conditions that affect the surface morphology and the crystal growth rate. These experimental conditions include concentration of the coating solution, degree of sub-cooling, agitation speed, retention time, and surface properties of the naked ibuprofen tablets. The results show that naked tablet coating by cooling crystallization is feasible and can be applied in the pharmaceutical industry.

关键词： coating     solution crystallization     ibuprofen tablets     sucrose    

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Molecular level simulations on multi-component systems —a morphology prediction method

C. SCHMIDT, J. ULRICH

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 49-54 doi: 10.1007/s11705-013-1307-8

摘要： The crystal morphology grown from a solution composed of an organic solvent, solute and additive can be predicted reliably by a computational method. Modeling the supersaturated solution as liquid phase is achieved by employing commercial software. The molecular composition of this solution is a required input parameter. The face specific diffusion coefficient of the solid (crystal surface) and liquid (solution) system is determined using the molecular dynamics procedure. The obtained diffusion coefficient is related to the specific face growth rate via the attachment energy of the pure morphology. The significant improvements are achieved in the morphology prediction because the investigation on the face growth rates in a complex growth environment (as multi-component solutions with additives) can be carried out based on the diffusion coefficients.

关键词： crystallization     morphology     molecular dynamics     solution    

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Progress in membrane distillation crystallization: Process models, crystallization control and innovative

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 647-662 doi: 10.1007/s11705-017-1649-8

摘要： Membrane distillation crystallization (MDC) is a promising hybrid separation process that has been applied to seawater desalination, brine treatment and wastewater recovery. In recent years, great progress has been made in MDC technologies including the promotion of nucleation and better control of crystallization and crystal size distribution. These advances are useful for the accurate control of the degree of supersaturation and for the control of the nucleation kinetic processes. This review focuses on the development of MDC process models and on crystallization control strategies. In addition, the most important innovative applications of MDC in the last five years in crystal engineering and pharmaceutical manufacturing are summarized.

关键词： membrane distillation crystallization     mathematics model     nucleation     separation     hybrid process    

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Effects of a structurally related substance on the crystallization of paracetamol

Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 79-87 doi: 10.1007/s11705-013-1308-7

摘要： Paracetamol (PCM) was crystallized from an isopropanol (IPA) solution containing various small amounts of metacetamol as an additive. The effect on the nucleation kinetics was studied by measuring the induction time to nucleation and the metastable zone width using focused beam reflectance measurements (FBRM) and attenuated total reflectance (ATR-UV/Vis) spectroscopy. Both the induction time and the metastable zone width were expressed as functions of the additive concentration. Small amounts of metacetamol (1–4 mol-%) were found to cause significant inhibition to the nucleation by extending both the induction time and the metastable zone width. A progressive change in the morphology of the paracetamol crystals from tabular to columnar habit was observed with increasing metacetamol concentration. The solvent also had a significant effect on the size of the paracetamol crystals as smaller crystals were obtained in IPA than in aqueous solution. The dissolution rate of paracetamol was improved by the incorporation of metacetamol with 4 mol-% having the most effect. A supersaturation control (SSC) approach was implemented for the PCM-IPA system with and without metacetamol in an attempt to control and obtain larger metacetamol-doped paracetamol crystals.

关键词： acetaminophen     metacetamol     crystallization     metastable zone width     induction time     supersaturation control    

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Interfacial induction and regulation for microscale crystallization process: a critical review

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 838-853 doi: 10.1007/s11705-021-2129-8

摘要： Microscale crystallization is at the frontier of chemical engineering, material science, and biochemical research and is affected by many factors. The precise regulation and control of microscale crystal processes is still a major challenge. In the heterogeneous induced nucleation process, the chemical and micro/nanostructural characteristics of the interface play a dominant role. Ideal crystal products can be obtained by modifying the interface characteristics, which has been proven to be a promising strategy. This review illustrates the application of interface properties, including chemical characteristics (hydrophobicity and functional groups) and the morphology of micro/nanostructures (rough structure and cavities, pore shape and pore size, surface porosity, channels), in various microscale crystallization controls and process intensification. Finally, possible future research and development directions are outlined to emphasize the importance of interfacial crystallization control and regulation for crystal engineering.

关键词： interfacial crystallization     heterogeneous nucleation     supersaturation     micro/nanostructure     process control and intensification    

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Utilizing melt crystallization fundamentals in the development of a new tabletting technology

Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 346-352 doi: 10.1007/s11705-014-1443-9

摘要： Increasing production effeciency and lowering costs are some of the many advantages melt crystallization technology offers over the conventional methodology of tabletting. A normal tablet consists of a pure shell or a coat and a separate core constituting the pharmaceutical active ingredient. Great emphasis is put on the purity of the shell since its purpose is to solely protect and deliver the active ingredient to its target. Melt crystallization is a purification (separation) process. It is discussed here for its ability to produce coated tablets, by separating the “coating” material from the “to be coated” material coming from one molten mixture. Molten drops of lutrol-ibuprofen mixture are produced using the drop forming technique. The subsequent analysis involves proving and quantifying the phase separation (coat purity). The mechanism of a crystallizing drop is shown as direct evidence of the ongoing process. Moreover, solidified tablet batches are analyzed for the purity of their coating by measuring the ibuprofen concentration. This optimization process is carried out through multiple stages of development and condition enhancements in order to produce the most pure tablet coating. As a result, a trial showing an almost purely coated tablet is presented here.

关键词： phase separation     melt crystallization     tablets     process optimization    

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Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

《化学科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 196-202 doi: 10.1007/s11705-016-1565-3

摘要： X-ray crystallography is a powerful strategy for 3-D structure determination of macromolecules, such as nucleic acids and protein-nucleic acid complexes. However, the crystallization and phase determination are the major bottle-neck problems in crystallography. Recently we have successfully developed synthesis and strategy of selenium-derivatized nucleic acids (SeNA) for nucleic acid crystallography. SeNA might not only provide the rational strategies to solve the phase determination problem, but also offer a potential strategy to explore crystallization solutions.

关键词： selenium     DNA     RNA     nucleic acid     crystallization    

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Preparation and crystallization kinetics of micron-sized Mg(OH)

Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU

《化学科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 130-138 doi: 10.1007/s11705-013-1332-7

摘要： Magnesium hydroxide is an important chemical, and is usually obtained from seawater or brine via precipitation process. The particle size distribution of magnesium hydroxide has great effects on the subsequent filtration and drying processes. In this paper, micron-sized magnesium hydroxide with high purity, large particle size and low water content in filter cake was synthesized via simple wet precipitation in a mixed suspension mixed product removal (MSMPR) crystallizer. The effects of reactant concentration, residence time and impurities on the properties of magnesium hydroxide were investigated by X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Malvern laser particle size analyzer. The results show that NaOH concentration and residence time have great effects on the water content and particle size of Mg(OH) . The spherical Mg(OH) with uniform diameter of about 30 μm was obtained with purity higher than 99% and water content less than 31%. Furthermore, the crystallization kinetics based on the population balance theory was studied to provide the theoretical data for industrial enlargement, and the simulation coefficients ( ) based on ASL model and C-R model are 0.9962 and 0.9972, respectively, indicating that the crystal growth rate of magnesium hydroxide can be well simulated by the size-dependent growth models.

关键词： magnesium hydroxide     precipitation     micron-sized     crystallization kinetics    

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Applications of the crystallization process in the pharmaceutical industry

Sohrab ROHANI

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 2-9 doi: 10.1007/s11705-009-0297-z

摘要： The applications of the crystallization technique in the pharmaceutical industry as a purification and separation process for the isolation and synthesis of pure active pharmaceutical ingredients (API), co-crystals, controlled release pulmonary drug delivery, and separation of chiral isomers are briefly discussed using a few case studies. The effect of process variables and solvent on the polymorphism and morphology of stavudine is discussed. The implementation of external control in the form of feedback and real-time optimal control using cooling and antisolvent crystallization of paracetamol in water-isopropyl alcohol is introduced. Two methods to prepare micron-sized drug particles, namely, micro-crystallization and polymer-coated API-loaded magnetic nanoparticles for pulmonary drug delivery, are discussed. The significance of co-crystals in drug administration is highlighted using the theophylline-nicotinamide co-crystal system. Resolution of chloromandelic acid derivatives, a racemic compound, is achieved using direct crystallization and diastereomeric salts crystallization. The crystal structures of diastereomeric salts of chloromandelic acid and phenylethylamine are determined. The structure comparison between the less soluble and more soluble salts shows that weak interactions such as CH/π interactions and van der Waals forces contribute to chiral recognition when the hydrogen bonding patterns are similar.

关键词： feedback     morphology     pulmonary     paracetamol     recognition    

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Importance of emulsions in crystallization—applications for fat crystallization

Sandra PETERSEN, K. CHALEEPA, Joachim ULRICH

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11705-013-1309-6

摘要： Emulsions and crystallization are two independent research topics which normally do not overlap although a combination of the two could be applicable to many areas. Here, the importance of emulsions in the field of fat crystallization is described. Three applications with industrial relevance were chosen for investigation: fat fractionation, the solidification of phase change materials and solid lipid nanoparticles. For fat fractionation and phase change materials, emulsification can be applied as a tool to improve the fat crystallization process, and thus the product quality of the crystallized fat. Furthermore, the use of emulsification creates new application fields such as solid lipid nanoparticles in the area of fat crystallization.

关键词： emulsion     fat crystallization     phase change material     emulsion fractionation     emulsion solidification    

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A review of optimization modeling and solution methods in renewable energy systems

《工程管理前沿（英文）》   页码 640-671 doi: 10.1007/s42524-023-0271-3

摘要： The advancement of renewable energy (RE) represents a pivotal strategy in mitigating climate change and advancing energy transition efforts. A current of research pertains to strategies for fostering RE growth. Among the frequently proposed approaches, employing optimization models to facilitate decision-making stands out prominently. Drawing from an extensive dataset comprising 32806 literature entries encompassing the optimization of renewable energy systems (RES) from 1990 to 2023 within the Web of Science database, this study reviews the decision-making optimization problems, models, and solution methods thereof throughout the renewable energy development and utilization chain (REDUC) process. This review also endeavors to structure and assess the contextual landscape of RES optimization modeling research. As evidenced by the literature review, optimization modeling effectively resolves decision-making predicaments spanning RE investment, construction, operation and maintenance, and scheduling. Predominantly, a hybrid model that combines prediction, optimization, simulation, and assessment methodologies emerges as the favored approach for optimizing RES-related decisions. The primary framework prevalent in extant research solutions entails the dissection and linearization of established models, in combination with hybrid analytical strategies and artificial intelligence algorithms. Noteworthy advancements within modeling encompass domains such as uncertainty, multienergy carrier considerations, and the refinement of spatiotemporal resolution. In the realm of algorithmic solutions for RES optimization models, a pronounced focus is anticipated on the convergence of analytical techniques with artificial intelligence-driven optimization. Furthermore, this study serves to facilitate a comprehensive understanding of research trajectories and existing gaps, expediting the identification of pertinent optimization models conducive to enhancing the efficiency of REDUC development endeavors.

关键词： renewable energy system     bibliometrics     mathematical programming     optimization models     solution methods    

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Effect of polyethylene glycol on the crystallization, rheology and foamability of poly(lactic acid) containing

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2074-2087 doi: 10.1007/s11705-023-2342-8

摘要： In this study, the rheological properties, crystallization and foaming behavior of poly(lactic acid) with polyamide 6 nanofibrils were examined with polyethylene glycol as a compatibilizer. Polyamide 6 particles were deformed into nanofibrils during drawing. For the 10% polyamide 6 case, polyethylene glycol addition reduced the polyamide 6 fibril diameter from 365.53 to 254.63 nm, owing to the smaller polyamide 6 particle size and enhanced interface adhesion. Rheological experiments revealed that the viscosity and storage modulus of the composites were increased, which was associated with the three-dimensional entangled network of polyamide 6 nanofibrils. The presence of higher aspect ratio polyamide 6 nanofibrils substantially enhanced the melt strength of the composites. The isothermal crystallization kinetics results suggested that the polyamide 6 nanofibrils and polyethylene glycol had a synergistic effect on accelerating poly(lactic acid) crystallization. With the polyethylene glycol, the crystallization half-time reduced from 103.6 to 62.2 s. Batch foaming results indicated that owing to higher cell nucleation efficiency, the existence of polyamide 6 nanofibrils led to a higher cell density and lower expansion ratio. Furthermore, the poly(lactic acid)/polyamide 6 foams exhibited a higher cell density and expansion ratio than that of the foams without polyethylene glycol.

关键词： poly(lactic acid)     foaming     microfibrillation     rheological property     crystallization    

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Control of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 423-431 doi: 10.1007/s11705-012-1211-7

摘要： 5-(Difluoromethoxy)-2-mercapto-1 -benzimidazole (DMB) was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope (PVM). We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

关键词： 5-(difluoromethoxy)-2-mercapto-1H-benzimidazole (DMB)     reactive crystallization     agglomeration     feeding rate     crystallization temperature     agitation rate    

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Modeling of specific structure crystallization coupling with dissolution

Yuanhui JI, Hongliang QIAN, Chang LIU, Xiaohua LU, Xin FENG, Xiaoyan JI,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 52-56 doi: 10.1007/s11705-009-0301-7

摘要： In this paper, the research framework for specific structure crystallization modeling has been proposed in which four steps are required in order to investigate the rigorous crystallization modeling by thermodynamics. The first is the activity coefficient model of the solution, the second is Solid-Liquid equilibrium, the third and fourth are the dissolution and crystallization kinetics modeling, respectively. Our investigations show that the mechanisms of complex structure formation and microphase transition can be analyzed by combining the dissolution and crystallization kinetics modeling. Moreover, the formation mechanism of the porous KCl has been analyzed, which may provide a reference for the porous structure formation in the advanced material synthesis.

关键词： structure crystallization     activity coefficient     reference     KCl     dissolution    

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标题 作者 时间 类型 操作

Additives effects on crystallization and morphology in a novel caustic aluminate solution decomposition

Ying ZHANG, Shili ZHENG, Yifei ZHANG, Hongbin XU, Yi ZHANG

期刊论文

The feasibility of coating by cooling crystallization on ibuprofen naked tablets

Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich

期刊论文

Molecular level simulations on multi-component systems —a morphology prediction method

C. SCHMIDT, J. ULRICH

期刊论文

Progress in membrane distillation crystallization: Process models, crystallization control and innovative

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

期刊论文

Effects of a structurally related substance on the crystallization of paracetamol

Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY

期刊论文

Interfacial induction and regulation for microscale crystallization process: a critical review

期刊论文

Utilizing melt crystallization fundamentals in the development of a new tabletting technology

Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH

期刊论文

Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

期刊论文

Preparation and crystallization kinetics of micron-sized Mg(OH)

Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU

期刊论文

Applications of the crystallization process in the pharmaceutical industry

Sohrab ROHANI

期刊论文

Importance of emulsions in crystallization—applications for fat crystallization

Sandra PETERSEN, K. CHALEEPA, Joachim ULRICH

期刊论文

A review of optimization modeling and solution methods in renewable energy systems

期刊论文

Effect of polyethylene glycol on the crystallization, rheology and foamability of poly(lactic acid) containing

期刊论文

Control of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

期刊论文

Modeling of specific structure crystallization coupling with dissolution

Yuanhui JI, Hongliang QIAN, Chang LIU, Xiaohua LU, Xin FENG, Xiaoyan JI,

期刊论文