A globally convergent composite ‐step trust‐region framework for real‐time optimization
AbstractInaccurate models limit the performance of model-based real-time optimization (RTO) and even cause system instability. Therefore, a RTO framework that guarantees global convergence in the presence of plant-model mismatch is desired. In this regard, the trust-region framework is intuitive and simple to implement for unconstrained problems. Constrained RTO problems are converted to unconstrained ones by the penalty function, and global convergence is guaranteed if the penalty coefficient is large enough. However, a sufficiently large penalty coefficient is hard to determine and may lead to numerical difficulties. Thi...
Source: AIChE Journal - November 13, 2023 Category: Science Authors: Duo Zhang,
Xiang Li,
Kexin Wang,
Zhijiang Shao Tags: RESEARCH ARTICLE Source Type: research
Marangoni effect on hydrodynamics and mass transfer behavior in an internal loop airlift reactor under elevated pressure
AbstractThe Marangoni effect on the hydrodynamics and mass transfer was studied in an internal loop airlift reactor with the addition of ethanol under elevated pressure. The overall gas holdupαg increased by ~10% and the gas –liquid volumetric mass-transfer coefficientkla increased by ~20% on average for each one bar increase in pressure. When the mole fraction of ethanolxE increased from 0 to 0.012,αg increased by ~110% andkla increased by ~50%. However, whenxE increased from 0.012 to 0.11,αg decreased by ~40% andkla decreased by ~25%. This volcano-shaped relationship between both hydrodynamics and mass transfer beha...
Source: AIChE Journal - November 13, 2023 Category: Science Authors: Yuelin Wang,
Xiankun Shen,
Huahai Zhang,
Tiefeng Wang Tags: RESEARCH ARTICLE Source Type: research
Achieving pH ‐universal electrosynthesis of formate under industrial‐grade current density by enriched selenium vacancies
AbstractElectrosynthesis of formate via CO2 reduction (CO2ER) is of great significance for completing carbon cycle, however, low CO2 utilization efficiency caused by slow reaction kinetics greatly hinder its large-scale application. Herein, we reported a ~50 nm-thick SnSe2 nanosheets with enriched Se vacancies, which exhibits an excellent catalytic activity for pH-universal formate electrosynthesis. In alkaline, neutral, and acidic electrolytes, this catalyst reached up to the maximum formate Faradaic efficiencies of 94.1%, 81.7%, and 78.1%, respectively. Under corresponding pH conditions, the maximum formate partial cu...
Source: AIChE Journal - November 10, 2023 Category: Science Authors: Zilin Zhao,
Xiangzhao Hu,
Yingnan Liu,
Dashuai Wang,
Bin Yang,
Zhongjian Li,
Xiang Gao,
Xiaobing Hu,
Lecheng Lei,
Yang Hou Tags: RESEARCH ARTICLE Source Type: research
Ionization ‐engineered two‐dimensional confined channels in GO membranes for highly efficient OH− separation
In this study, the concept of ionization engineering is applied to two-dimensional (2D) laminated membranes to facilitate OH− separation. This concept is demonstrated through the stacking of the self-designed sulfonated graphene oxide (SGO) nanosheets to fabricate 2D membranes. The SGO membranes enhance synergistically the OH− dialysis coefficients and separation factors when treating simulated NaOH/Na2WO4 alkaline wastewater, compared with the performance of 2D GO membranes and commonly adopted polymeric cation exchange membranes. Furthermore, the separation factor achieved by the SGO membranes is considerably higher ...
Source: AIChE Journal - November 9, 2023 Category: Science Authors: Yong Li,
Rui Jia,
Ruonan Tan,
Ziqiang Hong,
Jingjing Gu,
Peng Cui,
Suixin Zhang,
Hongwei Shao,
Jin Ran,
Cen ‐Feng Fu Tags: RESEARCH ARTICLE Source Type: research
A two ‐phase method of moments model for high‐impact polystyrene phase inversion conversion and molecular properties
AbstractA challenge for high-impact polystyrene (HIPS) production and design is the more accurate and low computational cost prediction of the phase separation and phase inversion conversion, the first conversion determining the onset of the two-phase system and the second conversion defining the pathway toward a complex, for example, salami-like morphology. In this work, a two-phase deterministic method of moments (MoM) model running in several minutes is therefore developed in the intermediate styrene conversion range (up to around 30%), considering for simplicity only diffusional limitations on termination on an average...
Source: AIChE Journal - November 9, 2023 Category: Science Authors: Chen ‐Xu Zhu,
Jie Jin,
Yi‐Yang Wu,
Freddy L. Figueira,
Mariya Edeleva,
Paul H. M. Van Steenberge,
Dagmar R. D'hooge,
Yin‐Ning Zhou,
Zheng‐Hong Luo Tags: RESEARCH ARTICLE Source Type: research
Insight into catalytic cracking pathways of n ‐pentane over bifunctional catalysts to produce light olefins
AbstractRevealing the reaction mechanism to guide the industrial production of targeted products still remains a grand challenge for catalytic cracking of light alkanes to olefins over metal-acid bifunctional catalyst. Herein, we systematically investigated the reaction mechanism of n-pentane cracking on the Ag/ZSM-5 bifunctional catalyst featuring both dehydrogenation and cracking capabilities. Specifically, overall cracking network of n-pentane was comprehensively constructed to show the roles of metal dehydrogenation sites and acid sites respectively, in which metal Ag could substitute the H of the Br ønsted acid site ...
Source: AIChE Journal - November 9, 2023 Category: Science Authors: Xinyang Zhang,
Yue Li,
Jiarong Lu,
Yuhang Hu,
Junfeng Chen,
Delun Ren,
Ze Li,
Qingchao Zhang,
Hao Yan,
Xiaobo Chen,
Yibin Liu,
Chaohe Yang Tags: RESEARCH ARTICLE Source Type: research
Layer ‐by‐layer adhesion of hydrogels for constructing heterogeneous microfluidic chips
AbstractHydrogel-based microfluidics have emerged as a promising platform for constructing organs-on-chips, offering in vivo-relevant micro-environments. However, the fabrication of complex microchannels using hydrogels remains challenging and often fails to replicate the intricate organ structures. Here, we introduce a novel methodology called “layer-by-layer adhesion” for the construction of complex microfluidic chips. Leveraging a hydrosoluble and photo-crosslinkable adhesive, chitosan methacryloyl (CS-MA), we successfully stitched various hydrogels together in a layer-by-layer fashion to form perfusable microchanne...
Source: AIChE Journal - November 9, 2023 Category: Science Authors: Chong Shen,
Yingjun Li,
Wenqi She,
Qin Meng Tags: RESEARCH ARTICLE Source Type: research
