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Effects of internals on macroscopic fluid dynamics in a bubble column

Chinese Journal of Chemical engineering 2025年第1期77卷 19-29页

作者： Shijie Liu Jin Liang Qin Li Hui Yu Haoliang Wang Xiangyang Li Chao Yang School of Chemical Engineering Sichuan UniversityChengdu 610065China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Petroleum Molecular&Process EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The effects of internals on liquid mixing and gas-liquid mass transfer have rarely been investigated in bubble columns,and the commonly used measurement method overestimates significantly overall gas ***,gas holdup measurement method is improved by conducting multi-point liquid level measurement and using net fluid volume instead of bed volume to calculate gas ***,a stable conductivity method for liquid macromixing has been established by shielding large bubbles using#16nylon ***,the influences of internal coverage(=12.6%,18.9% and 25.1%) on macroscopic fluid dynamics in a bubble column with a free wall area are systematically *** is found that the presence of internals has a notable effect on macroscopic fluid *** overall gas holdup and gas-liquid volumetric mass transfer coefficient decrease,and the macromixing time decreases with the increase of internal cross-sectional area *** are mainly caused by the uneven distribution of airflow due to the low resistance in the free wall *** design makes maintenance easier,but in reality,the reactor performance has *** improvements will be made to the reactor performance based on such a configuration through flow guidance using baffles.

关键词： Bubble column Internals Macroscopic fluid dynamics Mixing Mass transfer

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Chemical and engineering bases for green H2O2 production and related oxidation and ammoximation of olefins and analogues

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National Science Review 2024年第8期11卷 304-321页

作者： Minghua Qiao Xinggui Zhou Zexue Du Peng Wu Baoning Zong Collaborative Innovation Center of Chemistry for Energy Materials Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University State Key Laboratory of Chemical Engineering East China University of Science and Technology State Key Laboratory of Petroleum Molecular& Process Engineering Research Institute of Petroleum ProcessingSINOPEC State Key Laboratory of Petroleum Molecular& Process Engineering School of Chemistry and Molecular Engineering East China Normal University

Plastics,fibers and rubber are three mainstream synthetic materials that are essential to our daily lives and contribute significantly to the quality of our *** production of the monomers of these synthetic polymers usually involves oxidation or ammoximation reactions of olefins and ***,the utilization of C,O and N atoms in current industrial processes is <80%,which represents the most environmentally polluting processes for the production of basic *** innovation and integration of catalytic materials,new reaction pathways,and reaction engineering,the Research Institute of Petroleum processing,Sinopec Co.,Ltd.（RIPP） and its collaborators have developed unique H2O2-centered oxidation/ammoximation technologies for olefins and analogues,which has resulted in a ￥500 billion emerging industry and driven trillions of ￥s' worth of downstream *** chemical and engineering bases of the production technologies mainly involve the integration of slurry-bed reactors and microsphere catalysts to enhance H2O2production,H2O2propylene/chloropropylene epoxidation for the production of propylene oxide/epichlorohydrin,and integration of H2O2cyclohexanone ammoximation and membrane separation to innovate the caprolactam production *** review briefly summarizes the whole process from the acquisition of scientific knowledge to the formation of an industrial production technology by ***,the scientific frontiers of H2O2production and related oxidation/ammoximation processes of olefins and analogues are reviewed,and new technological growth points are envisaged,with the aim of maintaining China's standing as a leader in the development of the science and technologies of H2O2production and utilization.

关键词： hydrogen peroxide oxidation ammoximation propylene oxide epichlorohydrin cyclohexanone oxime

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Post-treatment of Ti-MWW zeolite with potassium fluoride for propylene epoxidation

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Frontiers of Chemical Science and engineering 2024年第8期18卷 37-47页

作者： Xintong Li Xianchen Gong Jilong Wang Shengbo Jin Hao Xu Peng Wu State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Epoxidation of propylene to propylene oxide(PO)with hydrogen peroxide(HPPO)is an environmentally friendly and cost-efficient process in which titanosilicates are used as ***-MWW is a potential industrial catalyst for this process,which involves the addition of HPPO to *** silanol groups generated during secondary crystallization unavoidably result in ring-opening of PO and inefficient decomposition of HPPO,which diminish the PO selectivity and the lifespan of *** address this issue,we conducted post-treatment modifications of the structured Bf-Ti-MWW catalyst with potassium fluoride aqueous *** quenching the silanol groups with potassium fluoride and implanting electron-withdrawing fluoride groups into the Ti-MWW framework,both the catalytic activity and HPPO utilization efficiency were ***,the ring opening reaction of PO was *** a continuous fixed-bed liquid-phase propylene epoxidation reaction,the KF-treated structured Ti-MWW catalyst displayed an exceptionally long lifespan of 2700 h,with a PO yield of 590 g·kg^(-1)·h^(-1).

关键词： titanosilicates Ti-MWW propylene epoxidation structured catalyst KF modification

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Numerical simulation of vortex breakdown in a cylindrical tank with rotating bottom and free surface using level set method

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Chinese Journal of Chemical engineering 2025年第1期77卷 293-300页

作者： Zepeng Zhao Qin Li Feng Ye Haoliang Wang Jianfeng Wang Hui Yu Xiangyang Li Chao Yang School of Chemical Engineering Sichuan UniversityChengdu 610065China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Petroleum Molecular&Process EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China

A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling *** order to control vortex breakdown within the chamber,this study first establishes a computational fluid dynamics simulation coupled with the level set *** by experimental results in literature,this method accurately simulates the position and shape of vortex breakdown,and also predicts the critical Reynolds numbers for the appearance and detachment of vortex breakdown bubbles from the ***,it precisely captures the gaseliquid interface and depicts the vortex breakdown phenomenon in the air above the liquid for the first ***,it predicts the impact of physical property of gaseliquid systems on vortex breakdown in response to significant changes in viscosity of microbial process systems.

关键词： Vortex breakdown Level set Microbial cultivation Micro-bioreactor

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Toward the rational design for low-temperature hydrogenation of silicon tetrachloride:Mechanism and data-driven interpretable descriptor

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Chinese Journal of Chemical engineering 2025年第3期79卷 172-184页

作者： Zhe Ding Li Guo Fang Bai Chao Hua Ping Lu Jinyi Chen Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Hubei Three Gorges Laboratory Yichang 443000China State Key Laboratory of Petroleum Molecular&Process Engineering Beijing 100190China

Low-temperature hydrogenation of silicon tetrachloride(STC)is an essential step in polysilicon *** addition of CuCl to silicon powder is currently a commonly used catalytic method and the silicon powder acts as both a reactant and a ***,the reaction mechanism and the structure-activity relationship of this process have not been fully *** this work,a comprehensive study of the reaction mechanism in the presence of Si and Cu_(3)Si was carried out using density functional theory(DFT)combined with experiments,*** results indicated that the ratedetermining step(RDS)in the presence of Si is the phase transition of Si atom,meanwhile,the RDS in the presence of Cu_(3)Si is the TCS-generation *** activation barrier of the latter is smaller,highlighting that the interaction of Si with the bulk phase is the pivotal factor influencing the catalytic *** feasibility of transition metal doping to facilitate this step was further *** Si disengage energy(E_(d))was used as a quantitative parameter to assess the catalytic activity of the catalysts,and the optimal descriptor was determined through interpretable machine *** was demonstrated that d-band center and electron transfer play a crucial role in regulating the level of *** work reveals the mechanism and structure-activity relationship for the low-temperature hydrogenation reaction of STC,and provides a basis for the rational design of catalysts.

关键词： Silicon tetrachloride Hydrogenation Reaction mechanism Interpretable machine learning Catalyst Structure-activity relationship

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A phenylboronic-acid functionalized liquid photonic crystal reagent for convenient and reliable detection of glucose

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Nano Research 2025年第2期18卷 699-707页

作者： Yanxuan Zhao Huimin Zhu Jianping Ge State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Institute of Eco-Chongming Shanghai 202162China

Photonic crystal sensing is an emerging technique that directly indicates the physicochemical changes with the change of structural ***,there are still challenges in material synthesis,ease of use,and reproducibility of detection for traditional photonic crystal(PC)***,a phenylboronic-acid functionalized SiO2 liquid photonic crystal(PBA-LPC)reagent was developed for reliable detection of glucose *** is convenient to prepare/use the LPC reagent because people only need to mix the responsive substance or the analyte solution with the LPCs in synthesis/*** sensing was based on the mechanism that the mixing of PBA-LPC reagent with glucose could release H+cations from PBA,which inhibited the deprotonation of the silanol group,weakened the particle surface charge,and blue-shifted the reflection of *** PBA LPC reagents responded to the glucose in different concentration ranges depending on the dosage of PBA,which ensured both a broad range detection and an accurate detection within a specific ***,it reported reproducible results due to the precise introduction of PBA and its sufficient interaction with ***,the PBA-LPC reagent showed a selective response to glucose and good anti-interference capability against the presence of NaCl,CaSO_(4),KH_(2)PO_(4),and Vitamin *** to these properties,the PBA-LPC reagent could serve as a new material for blood sugar tests and it also demonstrated the great potential of LPCs in sensing applications.

关键词： phenylboronic-acid liquid photonic crystal detection reagent glucose sensing

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Upcycling of polyethylene terephthalate to 1,4-cyclohexanedimethanol in water

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Science China Chemistry 2025年第5期68卷 2101-2109页

作者： Shuhui Fang Zhiwen Gao Xinrui Shi Min Zhang Wei Zhang Yue Liu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal University Engineering Center for Sustainable Carbon Science and Technology East China Normal University Institute of Eco-Chongming

The recycling of waste polyethylene terephthalate（PET）, an extensively used polymer as plastic and fiber materials, has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment. Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol（CHDM）, an important chemical in the production of advanced polyesters, predominantly use organic solvents, such as alcohols or dioxane. Herein, we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent. In this process, PET is sequentially hydrolyzed in water, hydrogenated to 1,4-cyclohexane dicarboxylic acid（CHDA）, and then reduced to CHDM. The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate. A Pd-based catalyst（e.g., Pd/C） selectively hydrogenates the arene ring of the PET monomer, terephthalic acid intermediate, and a Ru-Sn/C bimetallic catalyst reduces its COOH to CH2OH group. At optimized reaction conditions, a complete conversion of PET and 80.1% yield of CHDM are obtained. Alternatively, this approach can also efficiently produce CHDA from PET, with a yield up to 86.4%.

关键词： polyethylene terephthalate (PET) 1,4-cyclohexanedimethanol (CHDM) hydrogenation hydrogenolysis

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Tandem asymmetric propargylic amination/carboxylative cyclization reaction to chiral 5-methylidene-2-oxazolidinones using CO_(2) as C1 synthon

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Science China Chemistry 2025年第4期68卷 1402-1411页

作者： Zheng Zhang Zhi-Hao Zhang Ying Sun Yun-Hao Tang Yi-Zhuo Yang Feng Zhou Jian Zhou State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesShanghai Engineering Research Center of Molecular Therapeutics and New Drug DevelopmentSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

We report a tandem asymmetric Cu-catalyzed propargylic amination(ACPA)/Ag-catalyzed carboxylative cyclization(SCC)with CO_(2) to 5-methylidene-2-oxazolidinones;even with tetrasubstituted *** varying pyridine bisoxazoline(PYBOX)ligands;a general and highly enantioselective ACPA of unprecedentedly broad scope of secondary propargylic acetates and primary amines is ***α-aryl andα-aliphatic propargylic acetates could react with either aromatic or aliphatic primary amines to give the corresponding N-aryl or N-aliphatic ethynylamines withα-aliphatic orα-aryl groups in over 90%ee for use in the next *** key to developing this one-pot sequence is to use a chelator triethylenetetramine(TETA)to mask the copper ion;to avoid its negative effect on Ag-catalyzed cyclization;whilst releasing PYBOX to activate the silver *** the methylidene moiety;these oxazolidinones can be readily *** value of the sequence is further shown by the catalytic enantioselective total synthesis of(–)-cytoxazone and the potent ezetimibe analogue.

关键词： CO_(2) 2-oxazolidinone tandem sequence propargylic amination carboxylative cyclization

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Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li Rui-Rui Zhang Ke-Xin Li Shuang Wei Yu-Mei Liu Rui-Xia Liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

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Guest-induced topological transformation and near-infrared photothermal conversion featuring the Cp^(*)Rh unit via coordination-driven self-assembly

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Science China Chemistry 2025年第4期68卷 1345-1354页

作者： Xin-Yu Wang Qiu-Shui Mu Xiang Gao Guo-Xin Jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200438China

Herein;we perform a topological transformation by guest induction;converting[2]catenane Rh-1 into the Rh-3 molecular *** transformation involves the interaction of longerπ-acceptor half-sandwich RhⅢbimetallic building block B1[(Cp*Rh)_(2)(TPPHZ)](OTf)_(4) and π-donor bipyridyl ligands 4;4'-bis((pyridin-4-ylthio)methyl)-1;1'-biphenyl with four molecules of pyrene under ambient temperature in high ***;despite the involvement of a single pyrene molecule in modifying[2]catenane Rh-2 by transitioning B1 to B2;the underlying skeleton of Rh-2 remains ***;we explored the application of these substances before and after the reaction for near-infrared(NIR)photothermal *** meticulous structural analysis;the π-π stacking interactions play a pivotal role in stabilizing the abovementioned structures;enhancing the nonradiative transitions and initiating photothermal conversion in *** on the results;the introduction of pyrene significantly intensified the π-π stacking interactions but diminished the electron density between the adjacent NDI units;leading to a decrease in the NIR photothermal conversion efficiency(from 58.29%to 51.60%).In this study;an innovative approach is introduced for fabricating valuable half-sandwich-structured NIR photothermal conversion materials;and this research has promising prospects for enhancing the field of materials science with potential candidates for future development.

关键词： topological transformation guest-induced self-assembly molecular figure-of-eight near-infrared photothermal conversion

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