Crystallization Process and Simulation Calculation, Second Edition

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Industrial Crystallization".

Deadline for manuscript submissions: closed (20 April 2024) | Viewed by 26100

Special Issue Editors


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Guest Editor
State Key Laboratory of Chemical Engineering, Tianjin University, School of Chemical Engineering and Technology, Tianjin 300072, China
Interests: crystallization process; spherical crystallization; nucleation; crystal growth; crystal agglomeration; simulation; particle engineering
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Guest Editor
School of Chemistry, Biology and Materials Science, East China University of Technology, Nanchang 330013, China
Interests: polymorph nucleation; template-assisted crystallization; cocrystallizaiton design; porous biochar composites
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Institute of Shaoxing, Tianjin University, Shaoxing 312300, China
Interests: polymorphism; nucleation; crystal growth; industrial crystallization; crystal engineering
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Following the remarkable success of the first edition of this Special Issue, entitled “Crystallization Process and Simulation Calculation” (https://www.mdpi.com/journal/crystals/special_issues/crystallization_process2), we are pleased to announce this second edition.

As an important unit operation, crystallization is a process in which nucleation, growth, agglomeration, and breakage are regulated to produce high-quality crystals and achieve efficient separation and purification. In recent years, there have been some new research developments in crystallization processes. Process intensification techniques such as ultrasound and wet grinding are used to enhance the nucleation and breakage processes in crystallization, thereby preparing ultrafine powders and cube-like crystals. Spherical crystallization technology prepares spherical crystalline particles through crystal growth or agglomeration processes. Continuous crystallization has also gained growing interest due to its high productivity and consistency in product quality. These studies could provide innovative process design strategies and control methods for crystallizing a product with the required quality attributes and predictable performance. Since a crystallization process often presents with the characteristics of strong coupling, nonlinearity, and large lagging, it is a challenge to rationally design a robust, well-characterized process to efficiently crystallize and prepare a high-quality crystalline product. The development of process analytical technology that can provide fast and accurate inline or online measurements is of great importance in the design and control of crystallization processes. Simulation technology, e.g., molecular dynamics simulation and hydrodynamics simulation technology, can provide time- or location-dependent insights into the process at multiple scales. These experimental and simulation tools can greatly help to further investigate crystallization processes.

This Special Issue provides a platform for researchers to report results and findings regarding crystallization process technologies, simulation, process analytical technologies, and relevant crystallization studies.

Dr. Mingyang Chen
Dr. Jinbo Ouyang
Dr. Kangli Li
Guest Editors

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Keywords

  • nucleation and growth
  • agglomeration and breakage
  • process analytical technology
  • process intensification
  • continuous crystallization
  • spherical crystallization
  • molecular dynamics simulation
  • hydrodynamics simulation

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Related Special Issue

Published Papers (16 papers)

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Research

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12 pages, 3985 KiB  
Article
Modelling and Control of Thermal Stress in TSLAG (Tb3Sc1.95Lu0.05Al3O12) Magneto-Optical Crystals Grown by Czochralski Method
by Junling Ding, Yu Zhang, Yuankai Hao and Xiuwei Fu
Crystals 2024, 14(6), 564; https://doi.org/10.3390/cryst14060564 - 18 Jun 2024
Viewed by 577
Abstract
Tb3Sc1.95Lu0.05Al3O12 (TSLAG) crystals are novel and high-quality magneto-optical materials with the most promising application as the core component of Faraday devices. Cracking is an obstacle to TSLAG crystal growth and is closely influenced by [...] Read more.
Tb3Sc1.95Lu0.05Al3O12 (TSLAG) crystals are novel and high-quality magneto-optical materials with the most promising application as the core component of Faraday devices. Cracking is an obstacle to TSLAG crystal growth and is closely influenced by crystal thermal stress distribution. In this work, the evolution of thermal stress during TSLAG crystal growth in the initial Czochralski (Cz) furnace is numerically studied. The reasons for high thermal stress in TSLAG crystal are explained based on the results about the melt flow, the temperature distribution in the furnace, and the crystal/melt interface shape. A large crucible with a shallow melt is proposed to address the problem of significant variations in melt depth during TSLAG crystal growth. Based on the numerical results, the proposed design can stabilize the melt flow structure, suppressing changes in the crystal/melt interface shape and effectively improving thermal stress in the TSLAG crystal growth process, which contributes to precisely regulating the preparation of large-sized high-quality TSLAG crystals. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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12 pages, 3468 KiB  
Article
Numerical Simulations of the Impact of CaO/Al2O3 on the Structure and Crystallization Behavior of Red Mud
by Lei Xing, Zhi-Hui Li, Pei-Pei Du and Yue Long
Crystals 2024, 14(6), 526; https://doi.org/10.3390/cryst14060526 - 31 May 2024
Viewed by 527
Abstract
The problem of large stockpiles of red mud needs to be solved, and the use of red mud to prepare inorganic fibers is a new way of applying red mud on a large scale. The role of CaO/Al2O3 in the [...] Read more.
The problem of large stockpiles of red mud needs to be solved, and the use of red mud to prepare inorganic fibers is a new way of applying red mud on a large scale. The role of CaO/Al2O3 in the melting point and melt structure of red mud was investigated by molecular dynamics simulations and thermodynamic calculations. Liquid phase line temperatures for different CaO/Al2O3 systems were calculated using the Factsage program. The radial distribution function and the type of oxygen bonding were used to characterize the effect of different CaO/Al2O3 on the structure of the red mud melt. The melting point of MgAl2O4 is lower than that of CaTiO3 due to the fact that the type of oxygen bonding in MgAl2O4 is predominantly bridging oxygen bonds. When the red mud system has a low SiO2 content and CaO/Al2O3 is between 0.3 and 3.9, the melting point temperature increases significantly, which is not conducive to the fibrillation of the red mud melt. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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8 pages, 7054 KiB  
Communication
Role of Longitudinal Temperature Gradients in Eliminating Interleaving Inclusions in Casting of Monocrystalline Silicon Ingots
by Lindong Li and Changbo Fu
Crystals 2024, 14(5), 471; https://doi.org/10.3390/cryst14050471 - 17 May 2024
Viewed by 821
Abstract
Infrared analysis reveals the presence of interwoven inclusions, primarily comprised of silicon nitride and silicon carbide, in the casting process of monocrystalline silicon ingots. This study investigates how the longitudinal temperature gradient affects the removal of inclusions during the casting of monocrystalline silicon [...] Read more.
Infrared analysis reveals the presence of interwoven inclusions, primarily comprised of silicon nitride and silicon carbide, in the casting process of monocrystalline silicon ingots. This study investigates how the longitudinal temperature gradient affects the removal of inclusions during the casting of monocrystalline silicon ingots through simulations and comparative experiments. Two monocrystalline silicon ingots were cast, each using different longitudinal temperature gradients: one employing smaller gradients and the other conventional gradients. CGSim (Version Basic CGSim 23.1) simulation software was utilized to analyze the melt flow and temperature distribution during the growth process of quasi–monocrystalline silicon ingots. The findings indicate that smaller longitudinal temperature gradients lead to a more robust upward flow of molten silicon at the solid–liquid interface, effectively carrying impurities away from this interface and preventing their inclusion formation. Analysis of experimental photoluminescence and IR results reveals that although inclusions may not be observed, impurities persist but are gradually displaced to the top of the silicon melt through a stable growth process. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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11 pages, 2620 KiB  
Article
Elemental Uptake by Different Calcite Crystal Faces: An In Situ Study
by Mustafa Rezaei, Rinat Gabitov, Aleksey Sadekov, Alberto Perez-Huerta, Chiara Borrelli and Andrea Stiles
Crystals 2024, 14(5), 442; https://doi.org/10.3390/cryst14050442 - 7 May 2024
Cited by 1 | Viewed by 1360
Abstract
This study aims to evaluate relationships between elemental signatures in calcite and the crystallographic orientation of its planes. The ability of calcite (a widespread calcium carbonate mineral) to entrap various trace and minor elements in its structure is the foundation of multiple methods [...] Read more.
This study aims to evaluate relationships between elemental signatures in calcite and the crystallographic orientation of its planes. The ability of calcite (a widespread calcium carbonate mineral) to entrap various trace and minor elements in its structure is the foundation of multiple methods (also called proxies) to reconstruct paleoenvironment conditions (e.g., temperature, pH, and marine chemistry). Although several element-to-calcium ratios (E/Ca) are routinely measured in marine carbonates and are widely used in paleoclimate studies, some of the controls on the incorporation of these elements are still unclear. Here, we examine the effect of crystallography on (E/Ca)calcite by growing thin layers of calcite on differently oriented Iceland Spar substrates immersed in modified seawater solution. Newly grown calcite layers were examined with Laser Ablation Inductivity–Coupled Plasma Mass Spectrometry (LA-ICP-MS), Backscattered Electron Imaging (BSE), and Energy Dispersive X-ray Spectroscopy (EDS). We propose that the crystallographic orientation might slightly influence the incorporation of lithium (Li), sodium (Na), magnesium (Mg), sulfur (S), and barium (Ba) into the studied calcite faces and have no impact on the incorporation of boron (B), potassium (K), and strontium (Sr) at least under the conditions of our experiment. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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14 pages, 3314 KiB  
Article
Cocrystal Prediction Based on Deep Forest Model—A Case Study of Febuxostat
by Jiahui Chen, Zhihui Li, Yanlei Kang and Zhong Li
Crystals 2024, 14(4), 313; https://doi.org/10.3390/cryst14040313 - 28 Mar 2024
Cited by 2 | Viewed by 1327
Abstract
To aid cocrystal screening, a deep forest-based cocrystal prediction model was developed in this study using data from the Cambridge Structural Database (CSD). The positive samples in the experiment came from the CSD. The negative samples were partly from the failure records in [...] Read more.
To aid cocrystal screening, a deep forest-based cocrystal prediction model was developed in this study using data from the Cambridge Structural Database (CSD). The positive samples in the experiment came from the CSD. The negative samples were partly from the failure records in other papers, and some were randomly generated according to specific rules, resulting in a total of 8576 pairs. Compared with the models of traditional machine learning methods and simple deep neural networks models, the deep forest model has better performance and faster training speed. The accuracy is about 95% on the test set. Febuxostat cocrystal screening was also tested to verify the validity of the model. Our model correctly predicted the formation of cocrystal. It shows that our model is practically useful in practice. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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16 pages, 3936 KiB  
Article
Characterization and Formation Mechanism of Ag2MoO4 Crystals via Precipitation Method: Influence of Experimental Parameters and Crystal Morphology
by Sara Calistri, Alessandro Gessi, Giuseppe Marghella, Stefania Bruni and Alberto Ubaldini
Crystals 2024, 14(3), 254; https://doi.org/10.3390/cryst14030254 - 5 Mar 2024
Cited by 1 | Viewed by 1549
Abstract
Ag2MoO4 crystals were prepared by a precipitation method by mixing parent solutions of silver nitrate and sodium molybdate. The effects of experimental parameters such as temperature, concentration, and pH were studied. The samples were found to be crystalline, pure, and [...] Read more.
Ag2MoO4 crystals were prepared by a precipitation method by mixing parent solutions of silver nitrate and sodium molybdate. The effects of experimental parameters such as temperature, concentration, and pH were studied. The samples were found to be crystalline, pure, and monophasic in all cases, except in the case of very low pH. The precipitation leads to the formation of the cubic phase β and no secondary phase is present within the limits of detection of XRD and Raman spectroscopy. However, in some cases, at high temperature and high pH, silver oxide nanoparticles form on the surfaces of the crystals, which create a fluorescence background in the Raman spectra, which is otherwise absent. Analyses with the electron microscope have highlighted that the most common crystalline shape is octahedral, which is the most prevalent at low temperatures and pH around 7, but others are also possible, in particular at high temperatures. No growth occurs after precipitation, so crystals with different appearances form at the same time. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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17 pages, 2499 KiB  
Article
Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Two-Dimensional Population Balance Equations in Crystallization
by Cengceng Dong and Chunlei Ruan
Crystals 2024, 14(3), 234; https://doi.org/10.3390/cryst14030234 - 28 Feb 2024
Viewed by 974
Abstract
The population balance equations (PBEs) serve as the primary governing equations for simulating the crystallization process. Two-dimensional (2D) PBEs pertain to crystals that exhibit anisotropic growth, which is characterized by changes in two internal coordinates. Because PBEs are the hyperbolic equations, it becomes [...] Read more.
The population balance equations (PBEs) serve as the primary governing equations for simulating the crystallization process. Two-dimensional (2D) PBEs pertain to crystals that exhibit anisotropic growth, which is characterized by changes in two internal coordinates. Because PBEs are the hyperbolic equations, it becomes imperative to establish a high-resolution scheme to reduce numerical diffusion and numerical dispersion, thereby ensuring accurate crystal size distribution. This paper uses Euler’s first-order explicit (EE) method–Peridynamic Differential Operator (PDDO) to solve 2D PBE, namely, the EE method for discretizing the time derivative and the PDDO for discretizing the internal crystal-size derivative. Five examples, including size-independent growth with smooth and non-smooth distributions, size-dependent growth, nucleation, and size-independent/dependent growth for batch crystallization are considered. The results show that the EE–PDDO method is more accurate than the HR method and that it is as good as the fifth-order Weighted Essential Non-Oscillatory (WENO) method in solving 2D PBE. This study extends the EE–PDDO method to the simulation of 2D PBE, and the advantages of the EE-PDDO method in dealing with discontinuous and sharp front problems are demonstrated. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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13 pages, 5946 KiB  
Article
Effects of Dipentaerythritol and Cellulose as Additives on the Morphology of Pentaerythritol Crystals
by Wang Wei, Yangguang Li, Ningning Tian, Tian Xie, Dengpan Nie, Hongyan Li, Hongdong Quan, Xiuguo Yang, Luqian Ye, Xiaohe Li, Kangli Li and Ye Gao
Crystals 2024, 14(3), 219; https://doi.org/10.3390/cryst14030219 - 24 Feb 2024
Viewed by 1282
Abstract
The crystal habit of pentaerythritol (PE) crystals is usually rod-shaped, which may lead to low bulk density and bad flowability compared with low aspect ratio crystals. In this study, dipentaerythritol (DPE), methylcellulose (MC), and hydroxypropyl methylcellulose (HPMC) were selected as additives to modify [...] Read more.
The crystal habit of pentaerythritol (PE) crystals is usually rod-shaped, which may lead to low bulk density and bad flowability compared with low aspect ratio crystals. In this study, dipentaerythritol (DPE), methylcellulose (MC), and hydroxypropyl methylcellulose (HPMC) were selected as additives to modify the morphology of PE crystals. In the presence of DPE, the bulk density of PE crystals was improved, and the aspect ratio was decreased. The modified attachment energy (AE) model was conducted to analyze changes in PE crystal habits in the presence of DPE, which characterizes the intensity of the interaction between DPE molecules and PE crystal faces. Spherical pentaerythritol crystals can be successfully prepared by adding MC and HPMC solution, and the formation mechanism can be divided into five steps. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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17 pages, 4796 KiB  
Article
Effect of Y2O3 Concentration on the Surface and Bulk Crystallization of Multicomponent Silicate Glasses
by Akram Beniaiche, Aitana Tamayo, Nabil Belkhir, Fausto Rubio, Abdellah Chorfa and Juan Rubio
Crystals 2024, 14(3), 214; https://doi.org/10.3390/cryst14030214 - 23 Feb 2024
Viewed by 1120
Abstract
Multicomponent silicate glasses are crystallized by Y2O3 addition. Depending on the Y2O3 concentration, different crystalline phases evolve. In the absence of Y2O3, a multicomponent glass crystallizes as ZnSnO3, while with the addition [...] Read more.
Multicomponent silicate glasses are crystallized by Y2O3 addition. Depending on the Y2O3 concentration, different crystalline phases evolve. In the absence of Y2O3, a multicomponent glass crystallizes as ZnSnO3, while with the addition of just 3% of this oxide, ZnSnO3 no longer crystallizes and ZrSiO4 appears instead. Different yttrium silicate crystals are formed in all glasses containing Y2O3, but, while α-Y2Si2O7 and β-Y2Si2O7 are favored at low Y2O3 concentrations, the γ-Y2Si2O7 and y-Y2Si2O7 phases are favored at the maximum Y2O3 content. At a 12% Y2O3 concentration, barium and calcium silicate crystalline phases also evolve. Interestingly, the crystalline phases appearing on the surface of the material present different microstructures compared to crystals developed in the bulk. While the crystallized surface presents a tabular-shape type, crystallization in the bulk is of a prismatic type at low Y2O3 concentrations and of a globular (spherical) type at higher concentrations. The main crystal size ranges between 0.85 and 0.75 micrometers, but most of the crystals coalesce to form larger superstructures depending on the Y2O3 concentrations. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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18 pages, 7567 KiB  
Article
Numerical Microstructure Prediction for Lattice Structures Manufactured by Electron Beam Powder Bed Fusion
by Johannes A. Koepf, Julian Pistor, Matthias Markl and Carolin Körner
Crystals 2024, 14(2), 149; https://doi.org/10.3390/cryst14020149 - 31 Jan 2024
Cited by 2 | Viewed by 1156
Abstract
The latest advances in additive manufacturing have given rise to an increasing interest in additively built lattice structures due to their superior properties compared to foams and honeycombs. The foundation of these superior properties is a tailored microstructure, which is difficult to achieve [...] Read more.
The latest advances in additive manufacturing have given rise to an increasing interest in additively built lattice structures due to their superior properties compared to foams and honeycombs. The foundation of these superior properties is a tailored microstructure, which is difficult to achieve in additive manufacturing because of the variety of process parameters influencing the quality of the final part. This work presents the numerical prediction of the resulting grain structure of a lattice structure additively built by electron beam powder bed fusion. A thermal finite-difference model is coupled to a sophisticated cellular automaton-based crystal growth model, including nucleation. Numerically predicted grain structures, considering different nucleation conditions, are compared with experimentally derived EBSD measurements. The comparison reveals that nucleation is important, especially in fine lattice structures. The developed software, utilizing the nucleation model, is finally able to predict the as-built grain structure in lattice structures. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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24 pages, 7446 KiB  
Article
Controlling Crystal Growth of a Rare Earth Element Scandium Salt in Antisolvent Crystallization
by Josia Tonn, Andreas Roman Fuchs, Leon Libuda and Andreas Jupke
Crystals 2024, 14(1), 94; https://doi.org/10.3390/cryst14010094 - 19 Jan 2024
Viewed by 1625
Abstract
Recovering scandium from hydrometallurgical residue bears the potential of a better supply of an industry depending on imports from countries with more mineral resources than Europe. To recover scandium from unused metal production residue, strip liquors from a solvent extraction process are treated [...] Read more.
Recovering scandium from hydrometallurgical residue bears the potential of a better supply of an industry depending on imports from countries with more mineral resources than Europe. To recover scandium from unused metal production residue, strip liquors from a solvent extraction process are treated with an antisolvent to crystallize the ammonium scandium fluoride salt (NH4)3ScF6 with high product yields. However, high local supersaturation leads to strong nucleation, resulting in small crystals, which are difficult to handle in the subsequent solid-liquid separation. Reducing local supersaturation makes it possible to reduce nucleation and control crystal growth. Key operation parameters are the concentration of ethanol in the feed and its addition rate. The concentration of the antisolvent in the feed causes a shorter mixing time in the proximity of the antisolvent inlet, which leads to a smaller local supersaturation and therefore less nucleation and more crystal growth. Lowering the antisolvent addition rate enhances this effect. The crystal size distribution during and at the end of the fed-batch process is analyzed by SEM imagery of sampled and dried crystals. To produce reproducible crystal size distribution from SEM images the neural network Mask R-CNN has been trained for the automated crystal detection and size analysis. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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8 pages, 3901 KiB  
Communication
Surface-Energy-Driven Tin Whisker Growth on Pure Tin
by Yushuang Liu, Miaoyan Huang, Yue Chen, Ying Liu, Yumeng Zhu and Limin Cui
Crystals 2023, 13(12), 1643; https://doi.org/10.3390/cryst13121643 - 28 Nov 2023
Viewed by 1204
Abstract
Spontaneous Sn whisker growth, as a reliability issue in electronic assemblies, has drawn much attention in the past several decades. However, the underlying mechanism is still ambiguous. Herein, the growth of Sn whiskers on pure Sn with different specific surface areas was studied [...] Read more.
Spontaneous Sn whisker growth, as a reliability issue in electronic assemblies, has drawn much attention in the past several decades. However, the underlying mechanism is still ambiguous. Herein, the growth of Sn whiskers on pure Sn with different specific surface areas was studied to elucidate the effect of surface energy on Sn whisker growth. Though fabricated and cultivated using the same parameters, it was found that Sn whiskers were obtained on the sample of nano-Sn, which possesses excess surface energy, while no whiskers were observed on the sample of micro-Sn, indicating that surface energy plays a significant role in Sn whisker growth. In addition, the whiskering phenomenon is confirmed to be an abnormal recrystallization process according to the microstructure of the whisker root. Therefore, a Sn whisker growth mechanism companied with an abnormal recrystallization process is proposed, which is driven by the excess surface energy. This work provides a new perspective on understanding the long-standing Sn whiskering problem. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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12 pages, 5425 KiB  
Article
Thermal Field Design of a Large-Sized SiC Using the Resistance Heating PVT Method via Simulations
by Shengtao Zhang, Tie Li, Zhongxue Li, Jiehe Sui, Lili Zhao and Guanying Chen
Crystals 2023, 13(12), 1638; https://doi.org/10.3390/cryst13121638 - 26 Nov 2023
Cited by 2 | Viewed by 1933
Abstract
As the size of SiC crystals gradually increase, it becomes increasingly difficult to control the temperature distribution inside the crucible. In this study, numerical simulation tools were used to model the thermal field of SiC single crystal growth using the resistance heating PVT [...] Read more.
As the size of SiC crystals gradually increase, it becomes increasingly difficult to control the temperature distribution inside the crucible. In this study, numerical simulation tools were used to model the thermal field of SiC single crystal growth using the resistance heating PVT method. Through adjusting the relative position of the heater, adjusting the crucible and insulation structure, and setting up dual heaters, the temperature field distribution patterns under different conditions were obtained. The research results indicate that adjusting the relative positions of the heater, the crucible and insulation structure can achieve uniform temperature conditions under specific conditions. The use of dual heaters can achieve ideal crystal growth conditions with a growth interface temperature difference of less than 10 K, and an axial temperature gradient magnitude of about 10 K/cm, with a smaller edge axial temperature gradient, which is helpful to avoid edge polycrystalline formation and improve crystal quality. Meanwhile, combined with the top insulation layer, more energy-saving effects can be achieved, providing a reference for the preparation of large-sized SiC crystals. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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13 pages, 4957 KiB  
Communication
Heavy Alkyl-Benzene Sulfonate-Controlled Growth of Aragonite-Based Polymorphic CaCO3 Crystals in Emulsion
by Weiwei He, Junqing Hu, Weihao Sun, Jiqiong Liu, Hongguang Guo, Changming Zhao, Qingguo Wang, Xiangbin Liu, Meng Cai and Weiguang Shi
Crystals 2023, 13(7), 1107; https://doi.org/10.3390/cryst13071107 - 16 Jul 2023
Cited by 1 | Viewed by 1677
Abstract
The non-natural mineralization of CaCO3 with special structures or morphologies is generated during the migration of crude oil and is the main form of scale in alkaline/surfactant/polymer (ASP) flooding in oilfields, adversely affecting oil recovery and causing environmental pollution. To date, the [...] Read more.
The non-natural mineralization of CaCO3 with special structures or morphologies is generated during the migration of crude oil and is the main form of scale in alkaline/surfactant/polymer (ASP) flooding in oilfields, adversely affecting oil recovery and causing environmental pollution. To date, the mineralization of aragonite superstructures and the role of heavy alkyl-benzene sulfonate (HABS) in mineralization are still unclear. In this work, aragonite-based superstructures of CaCO3 crystals were obtained in an O/W emulsion with HABS to help deepen the understanding of the diversified growth of CaCO3 scaling in oilfields. As a result, rosette-like, bouquet-like, and dumbbell-shaped CaCO3 crystals with vaterite–aragonite, aragonite, and calcite–aragonite phases were formed with 200 mg/L HABS concentration at 45 °C for 60 min and spherical vaterite phase stabilized at a high HABS concentration (800 mg/L and 1000 mg/L). Rhombohedral calcite content experienced a fluctuation of about 40% as the HABS concentration varied. Needle-like and bundle-like aragonite precipitates were generated with increasing temperatures from 65 °C to 85 °C. Thus, HABS affects the nucleation and growth of the precipitated CaCO3 solid, leading to modifications in the structure and morphology of the crystals. The synergistic effect between HABS and temperature can regulate ion pairs with the calcium ions and block sites that are essential to the incorporation of new solutes into the crystal lattice, which leads to the heterogeneous nucleation of vaterite and aragonite on calcite, forming aragonite-based superstructures in kerosene emulsion. This work may enrich the understanding of CaCO3 mineralization in oilfields, and also provide a novel strategy for manufacturing organic–inorganic composites. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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Review

Jump to: Research

18 pages, 1378 KiB  
Review
Research Progress in the Industrial Crystallization of Citrate—A Review
by Yanyu Ma, Xueyou Qin, Hui Yan, Junjie Li, Chengwei Li, Mingke Lian, Xuemei Wei, Runpu Shen, Mingyang Chen, Kangli Li and Junbo Gong
Crystals 2023, 13(8), 1186; https://doi.org/10.3390/cryst13081186 - 30 Jul 2023
Cited by 2 | Viewed by 3205
Abstract
The citrate industry has a wide range of applications in food, pharmaceutical, and other fields. As a common class of food additives and functional supplements with tremendous development potential and strong core competitiveness, particles with good powder characteristics and functionalization are becoming one [...] Read more.
The citrate industry has a wide range of applications in food, pharmaceutical, and other fields. As a common class of food additives and functional supplements with tremendous development potential and strong core competitiveness, particles with good powder characteristics and functionalization are becoming one of the primary directions in the evolution of citrate into the high-end market. This article reviews the primary citrate crystallization techniques and examines the fundamental citrate crystallization mechanisms by describing citrate nucleation and growth during the industrial crystallization process. A variety of citrate hydrates are also summarized. The primary control conditions of the three essential product indices of purity, particle size, and grain shape are established. The need to take into account the density, fluidity, caking resistance, dissolution rate, suspension, bioavailability, and other indices of products is highlighted, along with applications for products that meet the purity and particle size requirements. While summarizing industrial citrate crystallization equipment, this paper also discusses the beneficial effect of continuous crystallization in achieving industrialization. Finally, the future development of citrate crystals is anticipated, and it is suggested that the combination of basic research and application research should be strengthened to explore the new application field of citrate crystals, and the automation and intelligence of the crystal preparation process should be realized as far as possible. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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13 pages, 1270 KiB  
Review
A Survey on Zeolite Synthesis and the Crystallization Process: Mechanism of Nucleation and Growth Steps
by Zahra Asgar Pour, Yasser A. Alassmy and Khaled O. Sebakhy
Crystals 2023, 13(6), 959; https://doi.org/10.3390/cryst13060959 - 15 Jun 2023
Cited by 11 | Viewed by 4776
Abstract
Zeolites, as a class of crystalline minerals, find a wide range of applications in various fields, such as catalysis, separation, and adsorption. More recently, these materials have also been developed for advanced applications, such as gas storage, medical applications, magnetic adsorption, and zeolitic-polymeric [...] Read more.
Zeolites, as a class of crystalline minerals, find a wide range of applications in various fields, such as catalysis, separation, and adsorption. More recently, these materials have also been developed for advanced applications, such as gas storage, medical applications, magnetic adsorption, and zeolitic-polymeric membranes. To effectively design zeolites for such intriguing applications, it is crucial to intelligently adjust their crystal size, morphology, and defect population in relation to crystal perfection. Optimizing these fundamental parameters necessitates a deep understanding of zeolite formation mechanisms, encompassing the thermodynamics and kinetics of nucleation steps as well as crystallite growth. In this review, we discuss the formation of zeolites from this perspective, drawing on recent studies that highlight new achievements in remodeling and modifying zeolite synthesis routes. The ultimate aim is to provide better comprehension and optimize the functionality of zeolites for the aforementioned applications. Full article
(This article belongs to the Special Issue Crystallization Process and Simulation Calculation, Second Edition)
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