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process synthesis with simultaneous consideration of inherent safety-inherent risk footprint

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Frontiers of chemical Science and Engineering 2018年第4期12卷 745-762页

作者： Andreja Nemet Jiri J.Kleme Zdravko Kravanja Faculty of Chemistry and chemical Engineering University of Maribor2000 MariborSlovenia Sustainable process Integration Laboratory NETME CentreFaculty of Mechanical EngineeringBmo University of Technology61669 Brno Czech Republic

process plants should be designed to be economically viable and environmentally friendly, while also being operable and maintainable during process implementation. The safety of processes is among the most important considerations in obtaining results that are more acceptably realistic, as it is linked to the availability and reliability of the process. Inherent safety can effectively be enhanced in the early stages of the design, when the main decisions on process design are made. The aim of this study is to enhance and select the appropriate risk assessment method and to incorporate it into process synthesis, using a mathematical programming approach. A mixed-integer, nonlinear programming (MINLP) model was used for the synthesis of a methanol production process, considering risk assessment during the synthesis. Risk assessment is performed simultaneously with the MINLP process synthesis, where the risk is determined either for the whole process as overall risk, or on a per unit-of-a-product basis. For the latter, a new measurement is proposed: the inherent risk footprint. The results of a case study led to two main conclusions: (i) Significantly safer designs can be obtained at negligible economic expense, and (ii) at higher production capacities, a lower inherent risk footprint can be achieved. The results also indicate that designs obtained using this method can have significantly increased inherent safety, while remaining economically viable.

关键词： inherent safety process design simultaneous risk assessment risk footprint methanol process

Recent Advances in Wide-Bandgap Organic-Inorganic Halide Perovskite Solar Cells and Tandem Application

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Nano-Micro Letters 2023年第5期15卷 254-297页

作者： Ting Nie Zhimin Fang Xiaodong Ren Yuwei Duan Shengzhong(Frank)Liu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Dalian National Laboratory for Clean energy iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Perovskite-based tandem solar cells have attracted increasing interest because of its great potential to surpass the Shockley-Queisser limit set for single-junction solar *** the tandem architectures,the wide-bandgap(WBG)perovskites act as the front absorber to offer higher open-circuit voltage(VOC)for reduced thermalization *** advantage of tunable bandgap of the perovskite materials,the WBG perovskites can be easily obtained by substituting halide iodine with bromine,and substituting organic ions FA and MA with *** date,the most concerned issues for the WBG perovskite solar cells(PSCs)are huge VOC deficit and severe photo-induced phase *** VOC loss and improving photostability of the WBG PSCs are crucial for further efficiency ***,scientists have made great efforts to overcome these key issues with tremendous *** this review,we first summarize the recent progress of WBG perovskites from the aspects of compositions,additives,charge transport layers,interfaces and preparation *** key factors affecting efficiency and stability are then carefully discussed,which would provide decent guidance to develop highly efficient and stable WBG PSCs for tandem application.

关键词： Efficiency Perovskite Solar cell Stability Wide-bandgap

Effect of turbulence-driven secondary flow on particle preferential concentration and clustering in turbulent square duct flows

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Particuology 2021年第2期19卷 70-83页

作者： Yanlin Zhao Yanzhi Wang Jun Yao International Joint Laboratory on Clean energy Science and Technology Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of Petroleum-BeijingBeijing 102249China

In this study,the preferential concentration and clustering of inertial particles in fully developed turbulent square duct flows are studied using large eddy simulations combined with Lagrangian approach,where the Reynolds number is equal to Reτ=600(based on the mean friction velocity and duct full height),and the particle Stokes number ranges from 0.0007 to *** results obtained for duct flows are compared with those for channel flows under the same working ***,the effect of the secondary flow on the particle concentration in duct flows is *** equation of particle motion is governed by the drag force,lift force,added mass force,pressure gradient force,and *** inter-phase interaction that was considered includes one-way and two-way *** simulations of a single phase are verified and in good agreement with the available literature *** the discrete phase,particles in the duct flow are found to be more dispersed in the vertical direction compared with the channel *** near-wall regions,a small fraction of particles tends to accumulate in duct corners,forming stable particle streaks under the effect of the secondary ***,most particles are likely to reside preferentially in the low-speed flow regions and form elongated particle streaks steadily in the middle region of duct or channel *** Voronoi diagram analysis shows that the near-wall secondary flows in the square duct could cause particle clusters to transfer from regions of high to low concentration,and this trend increases with particle *** addition,two-way coupling is found to enhance the near-wall particle accumulation and to promote particles to form more elongated streaks than one-way ***,the mechanism responsible for the particle preferential concentration in turbulent square duct flows is determined.

关键词： Secondary flow Preferential concentration Turbulence Particles Square duct

Outdoor aging of road asphalt and SBS modified asphalt

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Frontiers of chemical Science and Engineering 2011年第1期5卷 35-42页

作者： Li XIANG Juan TU Jian CHENG Guohe QUE State Key Laboratory of Heavy Oil processing China University of PetroleumQingdao 266555China Hubei Guochuang Advanced Material Ltd.Co. Wuhan 430073China Key Laboratory for Green chemical process of Ministry of Education Wuhan Institute of TechnologyWuhan 430073China Hubei Key Lab of Novel Reactor&Green chemical Technology Wuhan Institute of TechnologyWuhan 430073China

The process of performance degradation of road asphalt(RA)is regarded as *** present,better understanding of the thermal-oxidative aging of asphalt is achieved and the corresponding method to evaluate this process is developed;meanwhile,photo-oxidative aging(aging in an atmospheric environment,which is referred to as“outdoor aging”in this paper)of asphalt remains at the initial stages of scientific *** outdoor natural ultraviolet(UV)aging of RA and SBS modified asphalt(SBSMA)are investigated in this *** experimental results show that the basic performances of RA and SBSMA present similar change *** softening point increased,while the penetration and ductility decreased as the outdoor aging time passed by,and the 5℃ ductility(ductility measured at 5℃)of SBSMA decreased very *** group components of RA and SBSMA also change during UV *** content of asphaltene rose and that of aromatics and saturates decreased,while the content of resins changed ***,the Fourier transform infrared(FTIR)graphs show that the content of sulfoxide and carbonyl groups in RA and SBSMA increased significantly during the outdoor aging process.

关键词： asphalt SBS modified road asphalt outdoor aging ultraviolet

Preparation and oxygen permeation properties of SrFe(Cu)O_(3-δ) dense ceramic membranes

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Journal of Natural Gas Chemistry 2009年第1期18卷 45-49页

作者： Heng Zhang Tingting Wang Xinfa Dong Weiming Lin School of Chemistry and chemical Engineering Qufu Normal University Qufu 273165 Shandong China School of chemical and energy Engineering South China University of Technology Guangzhou 510640 Guangdong China

Mixed oxygen-ionic and electronic conducting membranes of SrFe（Cu）O3-δ were prepared by solid-state reaction method. The crystal structure, oxygen nonstoichiometry, and phase stability of the materials were studied by TGA and XRD. Oxygen permeation fluxes through these membranes were studied at operating temperature ranging from 750 to 950 ℃. Results showed that doping Cu in SrFeO3-δ compound had a significant effect on the formation of single-phased perovskite structure. For SrFe1-xCu2O3-δ series materials, the oxygen nonstoichiometry and the oxygen permeation flux increased considerably with the increase of Cu-doping content （x = 0.1-0.3）. The sintering property of the membrane decreased significantly when the Cu substitution amount reached 40%. SrFe0.7Cu0.3O3-δ showed high oxygen permeation flux, but SrCuO2 and Sr2Fe2O5 phases formed in the compound after oxygen permeation test induced cracks in the membrane.

关键词： perovskite mixed conductor oxygen permeation phase stability

Nitrous oxide (N_2O) emissions from a mesotrophic reservoir on the Wujiang River,southwest China

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Acta Geochimica 2017年第4期36卷 667-679页

作者： Xiaolong Liu Siliang Li Zhongliang Wang Guilin Han Jun Li Baoli Wang Fushun Wang Li Bai Tianjin Key Laboratory of Water resources and Environment Tianjin Normal University institute of Surface-Earth System Science Tianjin University School of Scientific Research China University of Geosciences (Beijing) Applied Radiation institute School of Environmental and Chemical EngineeringShanghai University

Aquatic ecosystems have been identified as a globally significant source of nitrous oxide(N_2O) due to continuous active nitrogen involvement, but the processes and influencing factors that control N_2O production are still poorly understood, especially in reservoirs. For that, monthly N_2O variations were monitored in Dongfeng reservoir(DFR)with a mesotrophic condition. The dissolved N_2O concentration in DFR displayed a distinct spatial–temporal pattern but lower than that in the eutrophic reservoirs. During the whole sampling year, N_2O saturation ranging from 144% to 640%, indicating that reservoir acted as source of atmospheric N_2O. N_2O production is induced by the introduction of nitrogen(NO_3^-, NH_4^+) in mesotrophic reservoirs, and is also affected by oxygen level and water temperature. Nitrification was the predominate process for N_2O production in DFR due to well-oxygenated longitudinal water *** values of estimated N_2O flux from the air–water interface averaged 0.19 μmol m^(-2)h^(-1) with a range of 0.01–0.61 μmol m^(-2)h^(-1). DFR exhibited less N_2O emission flux than that reported in a nearby eutrophic reservoir, but still acted as a moderate N_2O source compared with other reservoirs and lakes worldwide. Annual emissions from the water–air interface of DFR were estimated to be 0.32×10~5 mol N–N_2O, while N_2O degassing from releasing water behind the dam during power generation was nearly five times greater. Hence, N_2O degassing behind the dam should be taken into account for estimation of N_2O emissions from artificial reservoirs, an omission that historically has probably resulted in underestimates. IPCC methodology should consider more specifically N_2O emission estimation in aquatic ecosystems, especially in reservoirs, the default EF5 model will lead to an overestimation.

关键词： Nitrous oxide Mesotrophic reservoir Nitrogen dynamics IPCC methodology

Resolving Ketoprofen Using n-Octyl-d-glucamine as an Optical Resolution Agent

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Chinese Journal of chemical Engineering 2005年第4期13卷 568-571页

作者：朱圣东吴元欣喻子牛 School of chemical Engineering and Pharmacy Wuhan Institute of Chemical Technology College of Life Science and Technology Huazhong Agricultural University

The process of resolution of racemic ketoprofen using n-octyl-d-glucamine as an optical resolution agent was investigated. The process consists of preparation of the diastereomer salt of ketoprofen with n-octyl-d-glucamine, liberation of S-(+)-ketoprofen from its diastereomer salt and recovery of the remaining ketoprofen and n-octyl-d- glucamine. The suitable conditions for preparation of the diastereomer salt were methanol and ethyl acetate (1.1 by volume) as the solvent, the ratio of solvent volume to ketoprofen mass at 8ml:1g, and the molar ratio of ketoprofen to n-octyl-d-glucamine at 1:1. The preferred approach to liberate S-(+)-ketoprofen from its diastereomer salt was alkali dissolution, acid adjustment and ethyl acetate extraction. Racemization of the recovered ketoprofen could be achieved by reacting the recovered ketoprofen with 10% NaOH at 507 kPa for 6h. The recovered n-octyl-d- glucamine could be refined by acid dissolution and alkali adjustment. S-(+)-ketoprofen can be obtained with high optical purity and yield, showing that the present process is a practical and efficient one which can be used in industrial scale for preparation of S-(+)-ketoprofen.

关键词： ketoprofen resolution n-octyl-d-glucamine

Study on aerosol agglomeration using the airborne ultrasonic transducer

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Particuology 2023年第11期82卷 157-165页

作者： Yuxin Guo Guangxue Zhang Yunchao Li Hailin Gu Dingkun Yuan Maosheng Liu The institute for energy Engineering China Jiliang UniversityHangzhou310000China

Acoustic agglomeration technology use high-intensity acoustic field to make aerosol particles collide and condense rapidly. Existing studies have shown that 70%–90% of fine particles can be eliminated within minutes using compression drives and air-jet generators. Currently, there are limitations to the sound sources used. In this paper, an airborne ultrasonic transducer with a resonant frequency of 15 kHz is designed, followed by the corresponding numerical simulation and experiments for the evaluation of the vibration modal and sound pressure field. The sound pressure levels (SPL) of the open space and the agglomeration chamber can reach 150 dB and 156 dB, respectively. The agglomeration effect of water droplets, liquid phase smoke, solid phase smoke and mixed smoke is experimentally investigated, and the light transmittance rapidly increases from 8% to 60% within 4 s, 8 s, 5 s and 6 s, respectively. Agglomeration is also effective in the high-frequency range, and we infer that the acoustic wake effect is the predominant mechanism. The elimination effect is promoted with the increasing of SPL until the corresponding secondary acoustic effect is enhanced. Moreover, the agglomeration rate of higher concentration aerosol is significantly better than that of diluted aerosols in ultrasonic agglomeration process.

关键词： Acoustic agglomeration Airborne ultrasonic transducer Aerosol Sound pressure level Initial concentration

Interface modulation of twinned Pt Fe nanoplates branched 3D architecture for oxygen reduction catalysis

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Science Bulletin 2020年第2期65卷 97-104,87页

作者： Mingchuan Luo Yingnan Qin Menggang Li Yingjun Sun Chunji Li Yingjie Li Yong Yang Fan Lv Dong Wu Peng Zhou Shaojun Guo Department of Materials Science&Engineering College of EngineeringPeking UniversityBeijing 100871China College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042China MIIT Key Laboratory of Critical Materials Technology for New energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China BIC-ESAT College of EngineeringPeking UniversityBeijing 100871China Department of energy and resources Engineering College of EngineeringPeking UniversityBeijing 100871China

Highly-branched dendritic Pt-based nanocrystals possess great potential in catalyzing the oxygen reduction reaction(ORR),but encounter performance ceiling due to their poor thermal and electrochemical ***,we present a novel Pt Fe nanodendrites(NDs)branched with two-dimensional(2 D)twinned nanoplates rather than conventional 1 D nanowires,which breaks the ORR performance ceiling of dendritic catalysts by inducing the unique Pt-skin configuration via rationally thermal *** further hybridizing the Pt-skin Pt Fe NDs/C with amino-functionalized ionic liquids(ILs),we achieve an unprecedented mass activity of 3.15 A/mgPtat 0.9 V versus reversible hydrogen electrode(RHE)in the Pt Fe-based ORR electrocatalytic *** also show excellent electrocatalytic durability for ORR with negligible activity decay and no apparent structural change after 20,000 cycles,in sharp contrast to the nanowires branched Pt Fe NDs *** remarkable catalytic performance is attributed to a combination of several structural features,including 2 D morphology,twin boundary,partially ordered phase and strong coordination with amino *** work highlights the significance of stabilizing electrocatalytic structures via morphology tuning,which thus enables further surface and interface modification for performance breakthrough in ORR electrocatalysis.

关键词： Oxygen reduction reaction PtFe alloy Dendrities Nanoplates Ionic liquid