为进一步降低插电式串联混合动力汽车(Plug-in Series Hybrid Electric Vehicle, PSHEV)冷起动阶段的排放,对PSHEV进行整车建模,基于发动机的起停优化控制策略,建立电加热三元催化剂(Electrically Heated Catalyst System,EHCS)动力学模...为进一步降低插电式串联混合动力汽车(Plug-in Series Hybrid Electric Vehicle, PSHEV)冷起动阶段的排放,对PSHEV进行整车建模,基于发动机的起停优化控制策略,建立电加热三元催化剂(Electrically Heated Catalyst System,EHCS)动力学模型,并提出基于EHCS预热的PSHEV能量管理控制策略。仿真分析不同预热功率对EHCS温度的影响,对比该控制策略与原控制策略SOC值,并对比分析三元催化剂预热、后加热以及不加热三种策略下的冷起动排放。结果表明,PSHEV采用2 kW预热150 s的发动机起停优化的控制策略能以微小的燃油消耗代价,减少冷起动时HC/CO排放量。展开更多
Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient cataly...Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient catalytic way with good performance remains an enormous challenge.Herein,an internal electric heating(IEH)assisted mode was designed and proposed by the directly electrical-driven catalyst using the resistive heating effect.The Pt/Al2O_(3)on Fe foam(Pt/Al2O_(3)/FF)with unique threedimensional network structure was constructed.The catalysts were studied in a comprehensive way including X-ray diffraction(XRD),scanning electron microscopy(SEM)-mapping,in situ extended X-ray absorption fine structure(EXAFS),and in situ COFourier transform infrared(FTIR)measurements.It was found that the hydrogen evolution rate in IEH mode can reach up to above 2060 mmol·gPt^(−1)·min^(−1),which is 2–5 times higher than that of reported Pt based catalysts under similar reaction conditions in conventional heating(CH)mode.In combination with measurements from high-resolution infrared thermometer,the equations of heat transfer rate,and reaction heat analysis results,the Pt/Al2O_(3)/FF not only has high mass and heat transfer ability to promote catalytic performance,but also behaves as the heating component with a low thermal resistance and heat capacity offering a fast temperature response in IEH mode.In addition,the chemical adsorption and activation of MCH molecules can be efficiently facilitated by IEH mode,proved by the operando MCH-FTIR results.Therefore,the as-developed IEH mode can efficiently reduce the heat and mass transfer limitations and prominently boost the dehydrogenation performance,which has a broad application potential in hydrogen storage and other catalytic reaction processes.展开更多
Energy-saving and efficient monolithic catalysts are hotspots of catalytic purification of industrial gaseous pollutants.Here,we have developed an electrothermal catalytic mode,in which the ignition temperature requir...Energy-saving and efficient monolithic catalysts are hotspots of catalytic purification of industrial gaseous pollutants.Here,we have developed an electrothermal catalytic mode,in which the ignition temperature required for the reaction is provided by Joule heat generated when the current flows through the catalyst.In this paper,Mn/NiAl/NF,Mn/NiFe/NF and Mn/NF metal-based monolithic catalysts were prepared using nickel foam (NF) as the carrier for thermal and electrothermal catalysis of n-heptane.The results indicated that Mn-based monolithic catalysts exhibit high activity in thermal and electrothermal catalysis.Mn/NiFe/NF achieve conversion of n-heptane more than 99%in electrothermal catalysis under a direct-current (DC) power of 6 W,and energy-saving is 54% compared with thermal catalysis.In addition,the results indicated that the introduction of NiAl (or NiFe) greatly enhanced the catalytic activity of Mn/NF,which attributed to the higher specific surface area,Mn3+/Mn4+,Ni3+/Ni^(2+),adsorbed oxygen species (Oads)/lattice oxygen species (Olatt),redox performance of the catalyst.Electrothermal catalytic activity was significantly higher than thermal catalytic activity before complete conversion,which may be related to electronic effects.Besides,Mn/NiFe/NF has good cyclic and long-term stability in electrothermal catalysis.This paper provided a theoretical basis for applying electrothermal catalysis in the field of VOCs elimination.展开更多
基金the National Natural Science Foundation of China(Nos.22225807,21961132026,21878331,22021004,and 22109177)the National Key Research and Development Program(Nos.2020YFA0210903 and 2021YFA1501304)+4 种基金the PetroChina research institute of petroleum processing program(Nos.PRIKY21057 and PRIKY 21199)the Fundamental Research Funds for the Central Universities(No.2462020BJRC008)the support of Energy Internet Research Center,China University of Petroleum(Beijing),Haihe Laboratory of Sustainable Chemical Transformations(No.CYZC202105)the Beijing Synchrotron Radiation Facility(BSRF)Shanghai Synchrotron Radiation Facility(SSRF)during the XAFS measurements at the beamline of 1W1B,1W2B,and BL11B.
文摘Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient catalytic way with good performance remains an enormous challenge.Herein,an internal electric heating(IEH)assisted mode was designed and proposed by the directly electrical-driven catalyst using the resistive heating effect.The Pt/Al2O_(3)on Fe foam(Pt/Al2O_(3)/FF)with unique threedimensional network structure was constructed.The catalysts were studied in a comprehensive way including X-ray diffraction(XRD),scanning electron microscopy(SEM)-mapping,in situ extended X-ray absorption fine structure(EXAFS),and in situ COFourier transform infrared(FTIR)measurements.It was found that the hydrogen evolution rate in IEH mode can reach up to above 2060 mmol·gPt^(−1)·min^(−1),which is 2–5 times higher than that of reported Pt based catalysts under similar reaction conditions in conventional heating(CH)mode.In combination with measurements from high-resolution infrared thermometer,the equations of heat transfer rate,and reaction heat analysis results,the Pt/Al2O_(3)/FF not only has high mass and heat transfer ability to promote catalytic performance,but also behaves as the heating component with a low thermal resistance and heat capacity offering a fast temperature response in IEH mode.In addition,the chemical adsorption and activation of MCH molecules can be efficiently facilitated by IEH mode,proved by the operando MCH-FTIR results.Therefore,the as-developed IEH mode can efficiently reduce the heat and mass transfer limitations and prominently boost the dehydrogenation performance,which has a broad application potential in hydrogen storage and other catalytic reaction processes.
基金financially supported by National Natural Science Foundation of China (Nos. 51808037 and 21876010)Fundamental Research Funds for the Central Universities, China (No. FRF-IDRY-20–018)+1 种基金China Postdoctoral Science Foundation (No. 2020M680903)Natural Science Foundation of Guangdong Province, China (No. 2020A1515011197)。
文摘Energy-saving and efficient monolithic catalysts are hotspots of catalytic purification of industrial gaseous pollutants.Here,we have developed an electrothermal catalytic mode,in which the ignition temperature required for the reaction is provided by Joule heat generated when the current flows through the catalyst.In this paper,Mn/NiAl/NF,Mn/NiFe/NF and Mn/NF metal-based monolithic catalysts were prepared using nickel foam (NF) as the carrier for thermal and electrothermal catalysis of n-heptane.The results indicated that Mn-based monolithic catalysts exhibit high activity in thermal and electrothermal catalysis.Mn/NiFe/NF achieve conversion of n-heptane more than 99%in electrothermal catalysis under a direct-current (DC) power of 6 W,and energy-saving is 54% compared with thermal catalysis.In addition,the results indicated that the introduction of NiAl (or NiFe) greatly enhanced the catalytic activity of Mn/NF,which attributed to the higher specific surface area,Mn3+/Mn4+,Ni3+/Ni^(2+),adsorbed oxygen species (Oads)/lattice oxygen species (Olatt),redox performance of the catalyst.Electrothermal catalytic activity was significantly higher than thermal catalytic activity before complete conversion,which may be related to electronic effects.Besides,Mn/NiFe/NF has good cyclic and long-term stability in electrothermal catalysis.This paper provided a theoretical basis for applying electrothermal catalysis in the field of VOCs elimination.
