Article
Engineering, Chemical
Navid Mostoufi
Summary: An extended classification of powders based on their fluidization behavior is proposed in this study, taking into account the interparticle forces acting on particles and generating a diagram to depict the relationship between dimensionless interparticle force and Archimedes number. Clear boundaries between different fluidization behaviors were detected in the proposed diagram, and the advantage of considering these boundaries is to identify the type of fluidization when interparticle forces are significant.
CHEMICAL ENGINEERING SCIENCE
(2021)
Review
Engineering, Environmental
Yandaizi Zhou, Tielin Wang, Jesse Zhu
Summary: This study provides a comprehensive analysis and comparison of the minimum fluidization velocity (Umf) for different groups of powders in fluidized bed systems. The results show that the Umf for Group C+ particles is controlled by particle cohesion, while the Umf for Group A and B particles is primarily influenced by gravity.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Iman Soleimani, Jaber Shabanian, Jamal Chaouki
Summary: This study proposes two equivalent equations for quantifying interparticle forces (IPFs) in a gas-solid fluidized bed and examines their effects on agglomeration. The first equation, the generalized Umf deviation equation, correlates the magnitude of IPFs to the ratio of experimental and theoretical minimum fluidization velocities. The second equation, the generalized Dynamic Hausner Ratio (DHR) equation, relates the magnitude of IPFs to the agglomerate size as well as the DHR. These equations can be applied in various conditions and help quantify the resultant IPFs acting on particles. The opportunities and limitations of the proposed equations are discussed.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Physics, Fluids & Plasmas
Stewart A. Mallory, Ahmad K. Omar, John F. Brady
Summary: By introducing the concept of dynamic overlap concentration scales, additional universal features of the mechanical properties of active colloids have been identified. Through large-scale simulations of repulsive active Brownian particles, it has been confirmed that the run-length dependent concentration delineates distinct concentration regimes where interparticle collisions alter particle trajectories. The inclusion of these features qualitatively alters previous predictions of the behavior for active colloids.
Article
Engineering, Chemical
Kai Huang, Shuanghe Meng, Tao Zhang, Mao Ye, Wuqiang Yang, Zhongmin Liu
Summary: This study investigated the transition of fluidization behavior from Geldart B particles to A particles induced by temperature change using a developed high-temperature electrical capacitance tomography (ECT) sensor. Silica particles with a Sauter mean diameter of 237 μm and density of 2650 kg/m^3, typically Geldart B particles under ambient conditions, were fluidized in a 5.5 cm column from 20 to 600 degrees C. The ECT measurements showed that with increasing temperature, there was a decrease in minimum bubbling velocity (U(mb)), no bed expansion characteristic in the homogeneous fluidization regime, an absence of multiple-bubbles regime, and a larger bubble size. The pressure drop against superficial gas velocity curves at elevated temperatures confirmed homogeneous fluidization between the minimum fluidization velocity (U(mf)) and U(mb). Our analysis demonstrated that cohesive interparticle forces, which increase linearly with temperature, are responsible for the fluidization behavior transition of the silica particles.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Environmental
Iman Soleimani, Jaber Shabanian, Jamal Chaouki
Summary: The boundary between Geldart groups A and C is determined based on the magnitude of interparticle forces. Experimental validation shows that the agglomerate size increases with the increase of interparticle forces, supporting the proposed boundary.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Li Dai, Zhulin Yuan, Lei Guan, Kai Wu, Conghui Gu
Summary: This study discusses the effects of liquid saturation, gas velocity, and particle size on the global fluidization dynamics of Geldart D particles, finding that increasing liquid saturation and decreasing particle size intensifies bubble dynamics, with changes in fluidization regimes as gas velocity increases.
Article
Physics, Multidisciplinary
Abram H. Clark, Emily E. Brodsky, John Nasrin, Stephanie E. Taylor
Summary: We computationally study the frictional properties of sheared granular media subjected to harmonic vibration applied at the boundary. We find that weakening requires the absolute amplitude squared of the displacement to be sufficiently large relative to the confining pressure and that a previously unrecognized second process dependent on dissipation contributes to shear weakening under vibrations. This analysis provides a basis for predicting flows subjected to arbitrary external vibration.
PHYSICAL REVIEW LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Bing Ni, Guillermo Gonzalez-Rubio, Helmut Coelfen
Summary: This article focuses on the growth of tridimensional binary mesocrystals and the self-assembly of two colloidal nanocrystal ensembles, aiming to provide a basis for more rational synthesis of mesocrystals in the future. The study found that the formation of mesocrystals requires nanocrystals with defined surface faceting and functionalized nanocrystals with high colloidal stability. Furthermore, the growth process of 3D binary mesocrystals requires delicate control over the size, shape, surface chemistry, and self-assembly process of the nanocrystals.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Engineering, Chemical
Qingjin Zhang, Liangliang Fu, Guangwen Xu, Dingrong Bai
Summary: This study comprehensively analyzes the temperature effect on the minimum fluidization velocity (Umf) in fluidized-bed reactors. The analysis reveals the influence of temperature on Umf is determined by the relative importance of hydrodynamic forces and interparticle forces, which result in changes in gas properties, bed voidage, and physiochemical characteristics of particles. An equation is derived to predict the temperature influences on Umf under broad temperature conditions.
Article
Physics, Multidisciplinary
S. H. E. Rahbari, Michio Otsuki, Thorsten Poschel
Summary: The origins and spatiotemporal fluctuations of discontinuous shear thickening phenomena remain unknown. The authors numerically study the local injected power fluctuations across the discontinuous shear thickening transition, finding that rare fluctuations caused by frictional forces are governed by a simple fluctuation relation and the emergence of collective behavior in the particle's torque.
COMMUNICATIONS PHYSICS
(2021)
Article
Engineering, Chemical
Iman Soleimani, Navid Elahipanah, Jaber Shabanian, Jamal Chaouki
Summary: Interparticle forces (IPFs) are important in gas-solid fluidized beds, especially at elevated temperatures. Two approaches were developed in this study to quantify the magnitude of IPFs and its variation with temperature. The first method quantified thermally induced IPFs, while the second method quantified absolute values of IPFs based on voidage differences.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Physics, Fluids & Plasmas
Tomas Trewhela, J. M. N. T. Gray, Christophe Ancey
Summary: The study investigates the segregation of single large intruder particles in granular materials, finding that segregation rate is influenced by size ratio and local strain rate. Larger size ratios result in faster segregation rates, while ratios closer to unity lead to stronger rotation effects.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Multidisciplinary Sciences
Qiang Guo, Yuxuan Zhang, Azin Padash, Kenan Xi, Thomas M. Kovar, Christopher M. Boyce
Summary: The dynamics of granular materials play a critical role in various processes, with vibrating systems transforming chaotic bubble motion into a structured configuration. A constitutive relationship for solids stress predicts fluid-solid transitions and captures experimental structured bubbling patterns, offering potential for addressing issues in scale-up and optimal operation. Vibrating bubbling fluidized beds can produce more ordered structures as system size increases, indicating the scalability and potential of the proposed continuum model.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Engineering, Environmental
Shuyue Li, Yongmin Zhang, Wenjie Wang, Huan Wang
Summary: This study comprehensively evaluates the effect of particle density on hydrodynamics during the initial fluidization stage. It finds that empirical correlations for high-density particles may have significant errors in predicting the minimum fluidization velocity (Umf), and the predicted errors tend to increase with increasing particle density. Furthermore, the fluidization performance tends to deteriorate as the particle density increases.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Qing Han, Mengqing Shi, Linkai Han, Di Liu, Mingwei Tong, Yuxin Xie, Zhonghua Xiang
Summary: Developing highly efficient bifunctional oxygen electrocatalysts is crucial for zinc-air flow batteries. Metal-organic frameworks (MOFs) and covalent organic polymers (COPs) have emerged as promising alternatives due to their designable and controllable atomic-level structures. However, their catalytic performances are limited by conductivity and catalytic activity. In this study, nanosheet FeNi-MOF and iron phthalocyanine rich COP hybrid materials are assembled through the pi-pi stacking effect to create highly efficient bifunctional electrocatalysts. The resulting catalyst exhibits superior catalytic performance and stability, making it a promising candidate for zinc-air flow batteries.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Daria Grigorash, Dmytro Mihrin, Rene Wugt Larsen, Erling H. Stenby, Wei Yan
Summary: The article introduces a new approach to describe the cross-association between molecules, allowing for the simulation of weakly bound molecular complexes with different conformations in mixtures. By incorporating this approach into the equation of state, accurate predictions of vapor-liquid equilibrium and liquid-liquid equilibrium can be made. The new method is validated through experiments on alcohol and acid mixtures, with the results compared to experimental data, demonstrating its accuracy and reliability.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Mohammed Al-Sharabi, Daniel Markl, Vincenzino Vivacqua, Prince Bawuah, Natalie Maclean, Andrew P. E. York, Axel Zeitler
Summary: This study used terahertz pulsed imaging to investigate the transport process of different solvents into ceramic catalytic materials. The results showed that the heating rate of the samples influenced the water transport rate, while the viscosity of 1-octanol slowed down its transport.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chukwunonso Anyaoku, Sati Bhattacharya, Rajarathinam Parthasarathy
Summary: This study aimed to enhance understanding of settling dynamics in viscoelastic fluids by developing a semi-empirical correlation and a dimensionless ratio, which accurately described the characteristics of settling suspensions.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Antti I. Koponen, Janika Viitala, Atsushi Tanaka, Baranivignesh Prakash, Olli-Ville Laukkanen, Ari Jasberg
Summary: This study focuses on the development of foam application chemicals for the paper and board industry. The research explores the rheology of the polyvinyl alcohol foam used in the process. Measurements were conducted to determine the foam viscosity and slip flow. The results suggest that slip flow contributes significantly to the total flow rate, and the obtained viscosity and slip models provide a solid foundation for industrial processes.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Dalei Sun, Jinghui Cai, Yating Yang, Zhiwu Liang
Summary: In this study, Fe-doped alpha-Bi2O3 catalysts with different Fe/Bi molar ratios were synthesized and utilized in the carbonylation of isobutyl amine with CO2. The results showed that Fe doping significantly enhanced the catalytic abilities of alpha-Bi2O3.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Yuan Tian, Xinxin Wang, Yanrong Liu, Wenping Hu
Summary: This paper predicts the solubility of nitrogen gas in ionic liquids (ILs) using two quantitative structure-property relationship (QSPR) models. By combining machine learning methods and ionic fragments contribution method, the accuracy and reliability of the prediction models are improved.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Liwang Wang, Wei Liu, Pan Yang, Yulong Chang, Xiaoxu Duan, Lingyu Xiao, Yaoming Hu, Jiwei Wu, Liang Ma, Hualin Wang
Summary: This study investigates the effective phase interfacial area (ae) of hydro-jet cyclones at different injection angles. The results show that a 45 degrees upward incidence angle yields the most favorable flow field characteristics for efficient mass transfer. The significant enhancement in ae of the hydro-jet cyclones offers the advantage of reducing equipment volume and cost savings.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chuanjun Wu, Jiangzhi Chen, Jiyue Sun, I-Ming Chou, Shenghua Mei, Juezhi Lin, Lei Jiang
Summary: In this study, the solubility of H2S hydrate in water was measured using Raman spectroscopy. The results showed that the solubility increases with temperature under certain equilibrium conditions, and the solubility also depends on pressure and temperature under different equilibrium conditions. A thermodynamic model based on the van der Waals-Platteeuw theory was developed to predict the solubility, demonstrating its accuracy.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Lorenzo Brivio, Serena Meini, Mattia Sponchioni, Davide Moscatelli
Summary: This study investigates the influence of three main parameters and proposes a kinetic model to predict the optimal operating conditions for high yield of dimethyl terephthalate (DMT) in the chemical recycling process of polyethylene terephthalate (PET).
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Hongju Lin, Fanhui Liao, Yanchang Chu, Mingyu Xie, Lun Pan, Yuanyuan Wang, Lijian Leng, Donghai Xu, Le Yang, Gangfeng Ouyang
Summary: A honeycomb NiCo/C-Na catalyst with a micro-meso-macroporous structure has been fabricated and shown to have significantly higher catalytic activity for the decarboxylation of fatty acids. It also proves to be efficient in upgrading sludge HTL bio-crude, resulting in a biofuel with decreased viscosity and increased density.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Xiaoxian Li, Rui Li, Min Lin, Mingde Yang, Yulong Wu
Summary: A series of coated non-noble metal porous carbon catalysts were synthesized and applied to the aqueous-phase deoxygenation of algal bio-oil. One of the catalysts showed excellent deoxygenation selectivity and catalytic activity at 250 degrees C. The catalyst exhibited good hydrothermal stability and the reaction mechanism was proposed based on product analysis and active site analysis.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
M. V. Chudakova, M. V. Popov, P. A. Korovchenko, E. O. Pentsak, A. R. Latypova, P. B. Kurmashov, A. A. Pimenov, E. A. Tsilimbaeva, I. S. Levin, A. G. Bannov, A. V. Kleymenov
Summary: A series of catalysts with different potassium contents were prepared using solution combustion synthesis and characterized using various techniques. The results showed that the potassium content affected the phase composition and texture of the catalysts. The addition of a small amount of potassium resulted in a change in particle size distribution, leading to higher hydrogen yield. The Ni-1%K2O/Al2O3 catalyst exhibited the highest hydrogen yield at temperatures of 675 and 750 degrees Celsius.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Aliakbar Roosta, Nima Rezaei
Summary: In this study, we modified the electrolyte cubic plus association equation of state (e-CPA EoS) and integrated it with two electrical conductivity models to estimate the electrical conductivity of 11 monovalent electrolyte solutions in water. The modified e-CPA model demonstrated better performance and the hybridization with electrical conductivity models resulted in two predictive models for estimating the electrical conduction of dilute and concentrated electrolyte solutions. These predictive models showed relative average percentage deviations (AARD) of 11.15% and 13.87% over wide ranges of temperature and electrolyte concentration.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Haoren Niu, Jianzheng Wang, Qingzhu Jia, Qiang Wang, Jin Zhao, Fangyou Yan
Summary: A study developed two quantitative structure-property relationship models for the complexation performance of alpha- and beta-cyclodextrins and validated their stability and predictive ability through internal and external validation. The models showed robustness and satisfactory performance, as demonstrated by the experimental results and model validations. These models can effectively predict the binding constants between cyclodextrins and various types of molecules, providing valuable tools for cyclodextrin design.
CHEMICAL ENGINEERING SCIENCE
(2024)