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Organic-free,Ultrafast Synthesis of K-CHA Nano-aggregates with Various Morphologies and Their Adsorption Performances

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chemical Research in Chinese Universities 2024年第6期40卷 1151-1159页

作者： CHU Kailiang WANG Yaquan LIU Wenrong BU Lingzhen HUANG Yitong GUO Niandong QU Liping SANG Juncai LI Yaoning SU Xuemei ZHANG Xian Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering&TechnologyTianjin UniversityTianjin 300072P.R.China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192P.R.China

K-Chabazite(K-CHA)zeolites were synthesized with an ultrafast procedure through an eco-friendly and cost-effective“one-pot”*** solely employing colloidal silica and aluminum hydroxide in the K^(+)/Sr^(2+)system without the assistance of seeds,fluorides or organic structure as directing agents,the K-CHA nano-aggregates were successfully synthesized in a few *** crystallization behavior of the gels with different SiO_(2)/Al_(2)O_(3) molar ratios(SARs)was investigated using X-ray diffraction(XRD);scanning electron microscope(SEM);X-ray fluorescence(XRF);27Al and 29Si magic angle spinning nuclear magnetic resonance(MAS NMR);Fourier-transform infrared spectra(FTIR);UV-Raman *** the nucleation rates were changed with the SARs,three kinds of K-CHA nano-aggregates,namely,hamburger-,disk-and walnut-shaped,were obtained.A possible formation mechanism of the K-CHA nano-aggregates was ***,the walnut-shaped sample with an SAR of 7 possessed the largest pore volume and specific surface area,resulting in the highest methane adsorption ***,it exhibited a CH_(4)/N_(2) selectivity of more than 3 under relative pressures ranging from 0 to *** work offers guidance for modifying the stacking modes of other nano-sized zeolites.

关键词： Chabazite Organic structure directing agent(OSDA)-free Nano-aggregate Methane Adsorption separation

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Constructing diverse switchable circularly polarized luminescence via a single azobenzene polymer film

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Chinese chemical Letters 2025年第1期36卷 299-305页

作者： Xiang Wang Qingping Song Zixiang He Gong Zhang Tengfei Miao Xiaoxiao Cheng Wei Zhang State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu 241000China Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials School of Chemistry and Chemical EngineeringHuaiyin Normal UniversityHuaian 223300China

Recently circularly polarized luminescence(CPL)materials have attracted significant *** reversible dynamic property to these materials has been a key focus in cutting-edge fields,such as in high-level information ***,we provided a novel and general strategy involving handednessselective filtration and ground-state chiral self-recovery(CSR)in double film system to address this *** on this strategy,we achieved CPL switch through the reversible modulation of ground-state chirality including absorption and scattering circular dichroism(CD)signals over the full UV-visible wavelength range(365-700 nm)in a single azobenzene polymer(PAzo)*** importantly,by flexibly changing the type of fluorescent films,it is convenient to achieve general excited-state CSR,that is reversible switching of full-color including ideal white(CIE coordinate(0.33,0.33)),as well as room-temperature phosphorescent *** these CPL signals without almost any intensity decay after three cycles of onand-off *** results indicated that the trans-cis isomerization and ordered rearrangement of azobenzene units in PAzo film were the fundamental reasons for realizing CPL ***,based on this system we achieved dynamic visual encryption and decryption process including multiple decryption *** study provides an effective method for constructing a universally applicable chiroptical switch in excited state.

关键词： Circularly polarized luminescence Azobenzene polymer Multiple CPL Chiral switch Information encryption

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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal[3+2]annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Biotechnology and Health Sciences Wuyi UniversityJiangmen 529020China

Herein,the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO)complex catalyze asymmetric formal[3+2]cycloaddition between quinones and ynamides is explored,producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent ***,density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal[3+2]cycladdition Cu/SPDO complex DFT calculations

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Kinetics of hydrogen sulfide removal from coke oven gas over faujasite zeolite: Experimental and modeling studies

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Chinese Journal of chemical engineering 2025年第2期78卷 232-244页

作者： Feng Gao Sixiao Zhu Liping Chang Weiren Bao Jinghong Ma Junjie Liao State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Coal Science and Technology Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China School of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China

The removal of H_(2)S from coke oven gas (COG) is an important issue for the further utilization of COG. Zeolites could be used for industrial desulfurization owing to their high thermal stability and regenerability. However, further analysis on the kinetics of deep desulfurization using zeolites is necessary to provide relevant information for industrial design. In this study, the desulfurization breakthrough curves of faujasite (FAU) zeolite in COG were measured using a fixed bed reactor. The adsorption isotherm was investigated using the Langmuir, Freundlich, Temkin, Dubinin-Radushkevich models. The adsorption saturated capacity of H_(2)S was inversely related to the temperature. The results show that the Langmuir model best fits the adsorption isotherm with a lower value of root-mean-square-error (RMSE) and Chi-Square (χ^(2)), and the calculated activation energy is 14.62 kJ·mol^(−1). The adsorption kinetics were investigated using pseudo-first-order (PFO), pseudo-second-order (PSO), Bangham and Weber-Morris models. The Bangham model fitted the kinetic data well, indicating that pore diffusion is an influential factor in the adsorption process. The Weber-Morris model suggests that the adsorption rate was not solely determined by the pore diffusion, but was also influenced by the active site on the FAU zeolite. The adsorption breakthrough curves under different gas flow rates were fitted using the bed depth service time (BDST) model, and it provides an accurate prediction of the breakthrough time with a small relative error. The results of thermodynamic analysis demonstrated the feasibility and spontaneity (ΔG<0) and exothermic (ΔH<0) nature of the adsorption process of the FAU zeolite for H_(2)S under COG.

关键词： H_(2)S Coke oven gas FAU zeolite Kinetics Adsorption Fixed-bed

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Generation and modulation of nonreciprocal chirality to realize nonreciprocal CPL emission in polyurethane films

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Science China Chemistry 2025年

作者： Run Zhang Lujie Song Wenbo Yin Biao Zhao Jianping Deng State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology

Nonreciprocal chirality is essential for achieving nonreciprocal circularly polarized luminescence(CPL) emission, which shows great promise in a variety of potential applications due to its convenient handedness inversion just by flipping the ***, research on nonreciprocal CPL materials still remains severely limited, and further investigations in this direction are urgently needed. Based on our preceding studies dealing with nonreciprocal CPL materials, we in this study synthesized polyurethanes(PU) exhibiting nonreciprocal chirality, originating from oriented hard segments in the hard domains induced by micro-phase separation. By further introducing achiral helical polyacetylene, we observed a red-shift in the apparent Cotton effect, demonstrating the successful transfer of nonreciprocal chirality from PU to the achiral polyacetylene. Further incorporating achiral fluorescent sources into the PU systems containing polyacetylene realized nonreciprocal CPL emission. Our research offers a convenient and universal approach for generating and modulating nonreciprocal chirality and further enabling the realization of nonreciprocal CPL emission derived from polymeric materials.

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Hydrogenation kinetic of alkenes and aromatics over NiMo hydrotreatment catalysts

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Chinese Journal of chemical engineering 2025年第3期79卷 11-22页

作者： Wenbo Li Xinyao Fu Weiming Zhai Xingyang Huang Wenbin Chen Chen Zhang Wei Zhang Cuiqing Li Yong Luo Feng Liu Mingfeng Li Beijing Key Laboratory of Enze Biomass Fine Chemicals School of New Materials and Chemical EngineeringBeijing Institute of Petrochemical TechnologyBeijing 102617China SINOPEC Research Institute of Petroleum Processing Co. LTDBeijing 100083China State Key Laboratory of Organic-Inorganic Composites Research Center of the Ministry of Education for High Gravity Engineering and TechnologyBeijing University of Chemical TechnologyBeijing 100029China

Hydrotreatment is a critical process in the petrochemical industry to produce gasoline or *** kinetic models and accurate kinetic parameters of hydrotreatment reactions are important for the industrial reactor design and scale-up *** this work,hydrogenation kinetics of alkene and aromatic model compounds were studied thoroughly to provide deep understanding on alkene and aromatic hydrogenation behaviors in gasoline and diesel *** NiMo hydrotreatment catalysts were used to obtain experimental data of hydrogenation ***,1-octene,naphthalene and phenanthrene were used as model compounds of alkenes and ***-Hinshelwood-Hougen-Watson(LHHW)kinetic models for hydrotreatment reactions were *** addition,phase equilibrium calculations were combined with kinetic study,and it is discovered that using calculated liquid phase compositions as kinetic model input could greatly enhance the accuracy of kinetic models and the quality of kinetic parameters,leading to higher accordance with experimental *** kinetic models and phase equilibrium analysis,the effect of reaction conditions(temperature,pressure,and H_(2)/oil ratio)on reaction rates were also predicted and *** importance of phase equilibrium in kinetic analysis for hydrotreating reactions was demonstrated in this study,which provides an effective approach for future hydrotreatment reactor design and catalyst optimization.

关键词： Kinetic Hydrogenation Phase equilibria H_(2)/oil ratio

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An efficient nanodiamond-based monolithic foam catalyst prepared by a facile thermal impregnation strategy for direct dehydrogenation of ethylbenzene to styrene

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Chinese chemical Letters 2023年第5期34卷 332-336页

作者： Guifang Ge Xiaojing Wei Hongchen Guo Zhongkui Zhao State Key Laboratory of Fine Chemicals Department of Catalysis Chemistry and EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Nanodiamond(ND)has long been recognized as an effective carbocatalyst for synthesizing styrene via direct dehydrogenation(DDH).However,the induced drastic pressure drop of its powder form limits its industrial application in heterogeneous catalytic *** this work,we report a facile hexamethylenetetramine nitrate(HN)-assisted thermal impregnation(HNTI)strategy for fabricating a novel nanodiamondbased monolithic foam(ND/CNT-SiC-ms-HN)catalyst through a two-step approach:One is to soak the carbon nanotube-modified Si C foam(CNT-SiC)with the slurry composed of HN,KCl,Li Cl,and dispersed ND,and the other is to heat the slurry-soaked CNT-SiC(ND-HN-KCl-Li Cl/CNT-SiC)in N_(2) atmosphere at750℃.The as-synthesized ND/CNT-SiC-ms-HN monolithic foam features the enriched surface kenotic C=O by promoted ND dispersion and O-doping,abundant stuctural defects,and improved nucleophilicity by N-doping,originating from the promoted ND dispersion by thermal impregnation(TI)in KCl-LiCl molten salt(MS)and the presence of HN in the annealing *** a result,the ND/CNT-Si C-ms-HN monolithic foam catalyst by HNTI strategy exhibits 1.5 folds higher steady-state styrene rate(5.49 mmol g^(-1)h^(-1))associated with 98.4%of styrene selectivity compared to the ND-based monolithic foam catalyst(ND/CNT-SiC).Moreover,the ND/CNT-Si C-ms-HN monolithic foam shows excellent long-term stability for the direct dehydrogenation of ethylbenzene to *** work also comes up with a novel way of preparing other highly-dispersed nanocarbons-based monolithic foam catalysts with promising catalytic performance for diverse transformations.

关键词： Nanodiamond-based monolithic foam Heterogeneous catalysis Thermal impregnation Ethylbenzene direct dehydrogenation Styrene production

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Residence time distribution and heat/mass transfer performance of a millimeter scale butterfly-shaped reactor

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Chinese chemical Letters 2023年第4期34卷 332-337页

作者： Haicheng Lv Jundi Wang Zhongming Shu Gang Qian Xuezhi Duan Zhirong Yang Xinggui Zhou Jing Zhang State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

A millimeter scale butterfly-shaped reactor was proposed based on sizing-up strategy and fabricated via femtosecond laser engraving. An improvement of mixing performance and residence time distribution was realized by means of contraction and expansion of the reaction channel. The liquid holdup was greatly increased through connection of multiple mixing units. Structure optimization of the reactor was carried out by computational fluid dynamics simulation, from which the effect of reactor internals on mixing and the influence of parallel branching structure on heat transfer were discussed. The UV–vis absorption spectroscopy was used to determine the residence time distribution in the reactor, and characteristic parameters such as skewness and dimensionless variance were obtained. Further, a chained stagnant flow model was proposed to precisely describe the trailing phenomenon caused by fluid stagnation and laminar flow in small scale reactors, which enables a better fit for the experimental results of the asymmetric residence time distribution. In addition, the heat transfer performance of the reactor was investigated, and the overall heat transfer coefficient was 110–600 W m^(-2)K-1in the flow rate range of 10–40 m L/min.

关键词： Millimeter scale reactor Computational fluid dynamics Residence time distribution Chained stagnant flow model Overall heat transfer coefficient

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HZSM-5 zeolites undergoing the high-temperature process for boosting the bimolecular reaction in n-heptane catalytic cracking

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Chinese Journal of chemical engineering 2024年第2期66卷 136-144页

作者： Chenggong Song Zhenzhou Ma Xu Hou Hao Zhou Huimin Qiao Changchang Tian Li Yin Baitang Jin Enxian Yuan School of Chemical Engineering Changchun University of TechnologyChangchun130012China Department of Chemical and Biomolecular Engineering North Carolina State UniversityRaleighNC 27606USA School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225009China

High-temperature treatment is key to the preparation of zeolite ***,the effects of hightemperature treatment on the property and performance of HZSM-5 zeolites were studied in this work.X-Ray diffraction,N2physisorption,27Al magic angle spinning nuclear magnetic resonance(MAS NMR),and temperature-programmed desorption of ammonia results indicated that the hightemperature treatment at 650℃ hardly affected the inherent crystal and texture of HZSM-5zeolites but facilitated the conversion of framework Al to extra-framework Al,reducing the acid site and enhancing the acid ***,the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking,promoting the conversion and light olefins yield while inhibiting coke *** on the kinetic and mechanism analysis,the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al,which enhanced the acid strength,facilitated the bimolecular reaction,and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.

关键词： HZSM-5 n-Heptane Catalytic cracking High-temperature treatment Extra-framework Al

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Recent progress in lanthanide ions doped inorganic metal halide perovskites

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Journal of Rare Earths 2024年第2期42卷 237-250,I0001页

作者： Yiyan Zhang Tianyu Zhao Guanying Chen MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringState Key Laboratory of Urban Water Resource and EnvironmentKey Laboratory of Micro-systems and Micro-structuresMinistry of EducationHarbin Institute of TechnologyHarbin150001China

Benefiting from their large molar extinction coefficient,high carrier mobility,narrow and tunable emissions,inorganic metal halide perovskites(IMHPs) demonstrate great potential in various optoelectrical devices including solar cells,light emitting diodes and photodetectors in the past few *** ions doping,well-known as a modification method of semiconductors,has been extensively applied in IMHPs as *** metal ions have been doped in IMHPs including alkali metals,alkali earth metals,transition metals and lanthanide metals,which either improve their optical performances or induce intriguing brand-new *** them,lanthanide metals feature plentiful energy levels and stable optical properties and are one of the most noteworthy *** we review recent progress in lanthanide ions doped *** summarize Yb,Eu or Er ions singly doping in detail,which was the most investigated species in *** lanthanide ions are also reviewed ***,we introduce lanthanide ions multi-doped IMHPs and at last we put forward several potential development *** the interests in lanthanide ions doped IMHPs rise,researchers have made some achievements in the *** though,there are more unexplored *** there are review articles focusing on metal ions doped IMHPs or lanthanide ions doped perovskites,this review aims to provide an overall introduction of lanthanide ions doped *** review may help researchers learn about lanthanide ions doped IMHPs and is to inspire researchers to make further promotion in this field.

关键词： Halide perovskite Lanthanide Doping Rare earths

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