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Controlling solid form and crystal habit of triphenylmethanol by antisolvent crystallization in a microfluidic device

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Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： Jun Lu Jinrui Yan Yaohao Guo Junjie Qiu shuangliang zhao Bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

A reaction density functional theory study of solvent effect in the nucleophilic addition reactions in aqueous solution

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Green Energy & Environment 2022年第4期7卷 782-791页

作者： Cheng Cai Weiqiang Tang Chongzhi Qiao Bo Bao Peng Xie shuangliang zhao Honglai Liu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai200237China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical EngineeringGuangxi UniversityNanning530004China

Whereas the proper choice of reaction solvent constitutes the cornerstone of the green solvent concept,solvent effects on chemical reactions are not mechanistically well understood due to the lack of feasible molecular ***,by taking the case study of nucleophilic addition reaction in aqueous solution,we extend the proposed multiscale reaction density functional theory(RxDFT)method to investigate the intrinsic free energy profile and total free energy profile,and study the solvent effect on the activation and reaction free energy for the nucleophilic addition reactions of hydroxide anion with methanal and carbon dioxide in aqueous *** predictions of the free energy profile in aqueous solution for these two nucleophilic addition reactions from RxDFT have a satisfactory agreement with the results from the RISM and MD-FEP ***,the solvent effect is successfully addressed by examining the difference of the free energy profile between the gas phase and aqueous *** addition,we investigate the solvent effect on the reactions occurred near solid-liquid *** is shown that the activation free energy is significantly depressed when reaction takes place in the region within 10A distance to the substrate surface owing to the decrease of hydration free energy at the solid-liquid interface.

关键词： Reaction density functional theory Nucleophilic addition Solvent effect Charge models

Continuous synthesis of dolutegravir sodium crystals using liquid-gas heterogeneous microreactor

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Chinese Chemical Letters 2023年第3期34卷 302-307页

作者： Wei Luo Fen Liu Yaohao Guo Junjie Qiu Jinrui Yan shuangliang zhao Bo Bao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

In this work, a liquid-gas heterogeneous microreactor was developed for investigating continuous crystallization of dolutegravir sodium(DTG), as well as revealing reaction kinetics and mixing mechanism with 3-min data acquisition. The reaction kinetics models were established by visually recording the concentration variation of reactants over time in the microchannel via adding pH-sensitive fluorescent dye. The mixing intensification mechanism of liquid-gas flow was quantified through the fluorescent signal to indicate mixing process, demonstrating an outstanding mixing performance with a mixing time less than 0.1 s. Compared with batch crystallization, continuous synthesis of dolutegravir sodium using liquid-gas heterogenous microreactor optimizes crystal distribution size, and successfully modifies the crystal morphology in needle-like habit instead of rod-like habit. The microreactor continuous crystallization can run for 5 h without crystal blockage and achieve D90 of DTG less than 30 μm. This work provides a feasible approach for continuously synthesizing dolutegravir sodium, and can optimize the existing pharmaceutical crystallization.

关键词： Microreactor continuous crystallization Dolutegravir sodium Reaction kinetics Mixing mechanism Crystal morphology Process operation

Molecular dynamics simulation study onπ-πstacking of Gemini surfactants in oil/water systems

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Chinese Journal of Chemical Engineering 2022年第10期50卷 335-346页

作者： Jule Ma Peiwen Xiao Pingmei Wang Xue Han Jianhui Luo Ruifang Shi Xuan Wang Xianyu Song shuangliang zhao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Research Institute of Petroleum Exploration&Development(RIPED) PetroChinaBeijing 100083China Key Laboratory of Nano Chemistry(KLNC) CNPCBeijing 100083China Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir School of Environmental and Chemical EngineeringChongqing Three Gorges UniversityChongqing 404100China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Whereas theπ-πstacking interactions at oil/water interfaces can affect interfacial structures hence the interfacial properties,the underlying microscopic mechanism remains largely *** reported an all-atom molecular dynamics(MD)simulation study to demonstrate how the Gemini surfactants with pyrenyl groups affect the interracial properties,structural conformations,and the motion of molecules in the water/n-octane/surfactant ternary *** is found that the pyrenyl groups tend to be vertical to the interface owing to theπ-πstacking ***,a synergistic effect between theπ-πinteraction and steric hindrance is found,which jointly affects the coalescence of liquid ***,the existence of aromatic groups and a moderate number of surfactants helps to form *** work provides a molecular understanding of Gemini surfactants with aromatic groups in microemulsion preparation and applications.

关键词： Surfactants Interface Interfacial tension p-p stacking Microemulsion Molecular simulation

Single-atom catalysts modified by molecular groups for electrochemical nitrogen reduction

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Nano Research 2022年第10期15卷 9663-9669页

作者： Zengxi Wei Yuchang Liu Hongjie Liu Shaopeng Wang Minchen Hou Liwei Wang Dong Zhai shuangliang zhao Kefu Yu Shaolong Zhang Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China School of Marine Sciences Coral Reef Research Center of ChinaGuangxi Laboratory on the Study of Coral Reefs in the South China SeaGuangxi UniversityNanning 530004China MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured MaterialsNanning 530004China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China

Electrochemical nitrogen reduction reaction(eNRR)is one of the most important chemical reactions for the production of ammonia under ambient ***,the lack of in-depth understanding of the structure-activity relationship impedes the development of high-performance catalysts for ammonia ***,the density functional theory(DFT)calculations are performed to reveal the structure–activity relationship for the single-atom catalysts(SACs)supported on g-C_(3)N_(4),which is modified by molecular groups(i.e.,H,O,and OH).The computational results demonstrate that the W-based SACs are beneficial to produce ammonia with a low limiting potential(UL).Particularly,the W-OH@g-C_(3)N_(4) catalyst exhibits an ultralow UL of−0.22 V for *** the competitive eNRR selectivity can be identified by the dominant*N2 adsorption free energy than that of**** findings provide a theoretical basis for the synthesis of efficient catalysts to produce ammonia.

关键词： ammonia nitrogen reduction reaction single-atom catalysts(SACs) molecular groups density functional theory(DFT)calculations

Selective and sensitive fluorescence"turn-on"Zn^2+probes based on combination of anthracene,diphenylamine and dipyrrin

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Science China Chemistry 2017年第9期60卷 1212-1218页

作者： Xiaodong Wei Lulu Bu Weiqiang Tang shuangliang zhao Yongshu Xie Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chem&try and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Two fluorescence "turn-on" Zn^(2+) probes were developed by introducing an anthracenyl fluorophore through the linkage of a diphenylamino moiety at the 5-position of a dipyrrin ***,two compounds with weak fluorescence were designed,synthesized,and employed as CHEF(chelation enhanced fluorescence) type fluorescence "turn-on" Zn^(2+) probes,which exhibit dramatic fluorescence enhancement upon addition of Zn^(2+),showing high sensitivities and impressive detection limits of 13 and12 nM,respectively,better than their analogues containing simple aryl substituents at the 5 positions of a di-or tripyrrin *** addition,both of the probes exhibit good selectivity,short response time of less than 10 s and wide applicable pH ***,the weak fluorescence nature of the probes was rationalized based on viscosity dependence measurements and theoretical *** results provide further insight into the development of selective and sensitive zinc probes.

关键词： fluorescent probes, zinc probes, chelation enhanced fluorescence, sensitivity

Dominant role of wettability in improving the specific capacitance

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Green Energy & Environment 2019年第2期4卷 171-179页

作者： Tongtong Liu Kai Wang Yongxiu Chen shuangliang zhao Yongsheng Han State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and Technology

Here we report a strategy to enhance the energy density of supercapacitors by increasing the utilization rate of the specific surface area(SSA)via wettability improvement. The nonporous gold(NPG) film is used as the electrodes and the ionic liquid [EMIM]BF4 is the electrolyte. When the electrode is coated by paraffin, an increase of the contact angle leads to a remarkable reduction of the specific capacitance. While when acetonitrile is added into the electrolyte, the contact angle is decreased and the utilization rate of SSA is improved, which results in an increase of the specific capacitance. The addition of isopropyl acetate into the electrolyte leads to a further increase of the specific capacitance. To generalize the role of the wettability in improving the energy density, a carbon-based electrode is evaluated in the solution of potassium hydroxide. An addition of propyl alcohol into the potassium hydroxide solution leads to an increase of the specific capacitance, as well as a long-term stability of the supercapacitor. The role of conductivity in this study is excluded by designing experiments. This paper highlights the significance of wettability in determining the specific capacitance, showing an alternative to improve the energy density of supercapacitors.

关键词： Supercapacitor Energy density Specific capacitance Effective surface area Wettability

A reaction density functional theory study of solvent effects on keto-enol tautomerism and isomerization in pyruvic acid

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Chinese Journal of Chemical Engineering 2021年第3期34卷 10-16页

作者： Changjie Lu Weiqiang Tang Zijiang Dou Peng Xie Xiaofei Xu shuangliang zhao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

It is important to study the solvent effect on keto-enol tautomerism that has applications in many areas of chemical *** this work,we use a multiscale reaction density functional theory(Rx DFT)to study the keto-enol tautomerism and isomerization of pyruvic *** results show that both effects of solvation and water assistance could reduce the reaction *** water molecule participates the reaction as a catalyst to accept/give the protons with forming a hexagonal ring in the transition *** a result of this temporary and intermediate hexagonal ring,the solute configuration undergoes a small variation during the reaction,giving a diminished contribution to the intrinsic reaction free *** solvent distribution shows a local ordering behavior near the solute that also reduces the contribution of solvation effect to the reaction *** assistance plays a major role in both pre-reaction and postreaction *** terms of the driving force for the reaction,the effects of both solvation and water assistance are important.

关键词： Solvent effect Reaction density functional theory Pyruvic acid Tautomerism Isomerization

Improved oxidation of hydrogen off-gas by hydrophobic surface modification: A multiscale density functional theory study

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Particuology 2019年第3期17卷 28-35页

作者： Cheng Lian Cheng Cai Xiangjian Shen shuangliang zhao Xinhai Yu Honglai Liu State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and Technology Shanghai 200237 China School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 220237 China Research Center of Heterogeneous Catalysis and Engineering Science School of Chemical Engineering and Energy Zhengzhou University Zhengzhou 450001 China Key Laboratory of Safety Science of Pressurized System (MOE) School of Mechanical Engineering East China University of Science and Technology Shanghai 200237 China

A catalytic micro-reactor for converting hydrogen off-gas into water was recently developed, through which the conversion efficiency of hydrogen gas was greatly improved by hydrophobic modification of the catalytic substrate. Herein, a hybrid theoretical method is reported that combines density functional theory (DFT) on both the quantum and molecular scales. This method allows the microscopic study of the mechanism by which the surface catalytic reaction can be manipulated. Specifically, quantum DFT calculations are performed to quantify the molecular interaction between the catalytic substrate and reagent or product. Classical DFT investigations are subsequently carried out to determine the local concentrations of reagents near catalytic sites subject to different surface coating conditions. Finally, the reaction efficiency is determined from the local concentrations based on collision theory. This multiscale method provides molecular insight for quantifying the effect of catalytic surface modification on the reaction efficiency. The method reveals that an optimal surface hydrophobic modification can promote the densities of reagents near the substrate, while depleting the produced water. These two factors promote the conversion efficiency. The exclusion of produced water from the catalytic substrate is affected more by the degree of polymer grafting than by the chain length of hydrophobic polymer moieties.

关键词： Surface reaction Hydrophobic modification Density functional theory Multiscale