Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is...Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is appealing to build catalysts with ceria—an irreplaceable"reducible"component in three-way converters—to help eliminate the soot particles trapped in cGPFs via O_(2)-assisted combustion.While research aiming at understanding how these recipes function has continued for more than two decades,a universal model elucidating the roles of different"active oxygen"species is yet to be realized.In this perspective,by critically assessing the reported data about gasoline soot catalytic combustion over ceria catalysts,it is suggested that ceria ignites soot through contributing its lattice oxygen,giving rise to a"hot ring"region at the periphery of soot-catalyst interface.During the"re-oxidation"semi-cycles,electrophilic superoxides and/or peroxides(O_(x)^(n-))are produced at the Ce^(3+)and oxygen vacancy sites enriched in this collar-like region,and then work as key reactive phases for soot deep oxidation.Based on this"O_(x)^(n-)assisted"Mars-van Krevelen mechanism,several guidelines for ceria catalyst designing are proposed,ending with a summary about where future opportunities and challenges may lie in developing efficient and practical cGPF catalysts.展开更多
The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of production.However,the effectiveness of real-time optimization i...The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of production.However,the effectiveness of real-time optimization in gasoline blending relies on accurate blending models and is challenged by stochastic disturbances.Thus,we propose a real-time optimization algorithm based on the soft actor-critic(SAC)deep reinforcement learning strategy to optimize gasoline blending without relying on a single blending model and to be robust against disturbances.Our approach constructs the environment using nonlinear blending models and feedstocks with disturbances.The algorithm incorporates the Lagrange multiplier and path constraints in reward design to manage sparse product constraints.Carefully abstracted states facilitate algorithm convergence,and the normalized action vector in each optimization period allows the agent to generalize to some extent across different target production scenarios.Through these well-designed components,the algorithm based on the SAC outperforms real-time optimization methods based on either nonlinear or linear programming.It even demonstrates comparable performance with the time-horizon based real-time optimization method,which requires knowledge of uncertainty models,confirming its capability to handle uncertainty without accurate models.Our simulation illustrates a promising approach to free real-time optimization of the gasoline blending process from uncertainty models that are difficult to acquire in practice.展开更多
Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its sky.Unregulated exhaust emissions from motor vehicles,...Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its sky.Unregulated exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone formation.In this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were evaluated.It is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or hot.Compared to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated carbonyls.On a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,respectively.VOCs contributed to over 90%of the total OFP of the exhaust.In terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.展开更多
The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the And...The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the Anderson-Schulz-Flory(ASF)distribution law,and breaking through the distribution limitations to produce more gasoline components depends largely on the design and development of high-performance catalysts.In this paper,the recent research progress of bifunctional catalysts for gasoline production from syngas with high selectivity is summarized.This includes core-shell structure catalyst,microporous zeolite supported catalyst,mesoporous zeolite supported catalyst,metal oxide-zeolite relay catalyst.Moreover,the reaction mechanisms are summarized.The future prospects of catalysts for the high-selectivity synthesis of gasoline from syngas is also discussed.The current review will provide insights into the bifunctional catalysts for one-step syngas conversion to gasoline.展开更多
Efficient and secure refueling within the vehicle refueling systems exhibits a close correlation with the issues concerning fuel backflow and gasoline evaporation.This paper investigates the transient flow behavior in...Efficient and secure refueling within the vehicle refueling systems exhibits a close correlation with the issues concerning fuel backflow and gasoline evaporation.This paper investigates the transient flow behavior in fuel hose refilling and simplified tank fuel replenishment using the volume of fluid method.The numerical simulation is validated with the simplified hose refilling experiment and the evaporation simulation of Stefan tube.The effects of injection flow rate and injection directions have been discussed in the fuel hose refilling part.For both the experiment and simulation,the pressure at the end of the refueling pipe in the lower located nozzle case is 30%higher than that in the upper located nozzle case at a high flow rate,and the backflow phenomenon occurs at the lower filling mode.The fluid will directly flush into the first pipe elbow,changing the flow pattern from bubble flow to slug flow,which results in low-frequency and high-amplitude flowpressure fluctuations.Ahexane refueling system,consisting of a refueling pipe,fuel tank and a vapor return line,is analyzed,in which hexane evaporation is considered.At the early refueling period,a higher refueling rate will lead to more obvious splashing,which leads to a higher average mass of hexane vapor and pressure in the tank.Two optimized fuel tank designs are examined.The lower fuel tank filling port exhibits significantly lower vapor hexane in the fuel tank compared to the other design,resulting in a reduction of 200 Pa in the peak pressure in the tank,which contributes to a substantial reduction of gasoline loss during tank filling.展开更多
In order to improve the steady and dynamic characteristic of the idle speed control and study the performance of the fuzzy control method for the idle speed control, a fuzzy control system is developed to control the ...In order to improve the steady and dynamic characteristic of the idle speed control and study the performance of the fuzzy control method for the idle speed control, a fuzzy control system is developed to control the idle speed of gasoline engine. The construction and working principle of the fuzzy controller are described, and the design procedure of the fuzzy controller is given in detail. The control parameters are determined by computer simulation. The simulation and experiments on the engine test bench show that the idle speed is controlled accurately both in stationary and in dynamic states, and the fuzzy control method is robust to the changes of engine parameters.展开更多
Based on the introduction of the basic combustion concept of gasoline direct injection(GDI)engine and its operation under different operating conditions,HC emission mechanisms of the GDI en-gine are analyzed.And HC em...Based on the introduction of the basic combustion concept of gasoline direct injection(GDI)engine and its operation under different operating conditions,HC emission mechanisms of the GDI en-gine are analyzed.And HC emission characteristics of the GDI engine are compared with the PFI en-gine via a comparison test based on the FTP-75 driving cycle.It can be concluded that the GDI engineis facing a big challenge in meeting the future's HC emission standard.Reasons for the higher HC e-missions of the GDI engine are discussed and the ways for HC emission control are given.展开更多
To investigate the characteristics of the condensation in gasoline vapor condensation recovery,the condensation process of gasoline vapor with turbulent flow in a vertical tube is simulated based on the gas-liquid two...To investigate the characteristics of the condensation in gasoline vapor condensation recovery,the condensation process of gasoline vapor with turbulent flow in a vertical tube is simulated based on the gas-liquid two-phase flow model.An effective diffusion coefficient is used to describe mass diffusion among the species of gasoline vapor.Several variables including temperature,pressure,liquid film thickness and the variation of the Nusselt number in the tube are simulated.The effects of the inlet-to-wall temperature difference and the Reynolds number on the condensation rate and the Nusselt number are obtained by modelling.The results show that heat transfer and condensation can be enhanced significantly by increasing the inlet Reynolds number.However,the increase in the inlet-to-wall temperature difference has little effect on the condensation rate.It is also found that the gasoline vapor condensation rate is influenced greatly by the mass transfer resistance.The comparison of results from the model with previous experiments shows a good agreement.展开更多
The effect of olefins on formation of sulfur compounds in FCC gasoline was studied in a small-scale fixed fluidized bed （FFB） unit at temperatures ranging from 400℃ to 500℃, a weight hourly space velocity （WHSV）...The effect of olefins on formation of sulfur compounds in FCC gasoline was studied in a small-scale fixed fluidized bed （FFB） unit at temperatures ranging from 400℃ to 500℃, a weight hourly space velocity （WHSV） of 10 h-1, and a catalyst/oil ratio of 6. The results showed that C4--C6 olefins contained in the FCC gasoline could react with HzS to form predominantly thiophenes, alkyl-thiophenes as well as a fractional amount of thiols, while large molecular olefins such as heptene could react with hydrogen sulfide to form benzothiophenes. The amount of sulfur compounds formed at different tem- peratures over different catalysts were in proportion to the mass fractions of olefins in the feedstock, with the amount of sulfur compounds formed over REUSY catalyst exceeding those formed over the shape selective zeolite catalyst owing to the effect of catalyst performance and the impact of catalyst on the degree of olefin conversion. The amount of sulfur compounds generated and their increase reached a maximum at 450℃ and a minimum at 400℃ because of the influence of temperature on the thermodynamic and kinetic constants for formation of sulfur compound as well as on the olefin conversion degree. Based on the above-mentioned study, a reaction network and a model for prediction of sulfur compounds generated upon reaction of olefins in FCC gasoline with HES were established.展开更多
In this paper, the effect of MMT on the induction period of unleaded motor gasoline was studied, the manganese concentration, storage period of MMT-blended gasoline and environmental variables such as temperature and ...In this paper, the effect of MMT on the induction period of unleaded motor gasoline was studied, the manganese concentration, storage period of MMT-blended gasoline and environmental variables such as temperature and radiation intensity were considered to be main factors affecting the induction period of gasoline,when MMT-blended gasoline was exposed to light. It is found from experiments that the addition of MMT can improve the induction period of gasoline that is shielded from light, and reduce the induction period remarkably,when the gasoline is exposed to light. However, the radiation intensity is proved to be the leading influencing factor among all the environmental variables investigated.展开更多
Regulated and unregulated emissions from four passenger cars fueled with methanol/gasoline blends at different mixing ratios （M15,M20,M30,M50,M85 and M100） were tested over the New European Driving Cycle （NEDC）.Vo...Regulated and unregulated emissions from four passenger cars fueled with methanol/gasoline blends at different mixing ratios （M15,M20,M30,M50,M85 and M100） were tested over the New European Driving Cycle （NEDC）.Volatile organic compounds （VOCs） were sampled by Tenax TA and analyzed by thermal desorption-gas chromatograph/mass spectrometer （TD-GC/MS）.Carbonyls were trapped on dinitrophenylhydrazine （DNPH） cartridges and analyzed by high performance liquid chromatography （HPLC）.The results showed that total emissions of VOCs and BTEX （benzene,toluene,ethylbenzene,p,m,o-xylene） from all vehicles fueled with methanol/gasoline blends were lower than those from vehicles fueled with only gasoline.Compared to the baseline,the use of M85 decreased BTEX emissions by 97.4%,while the use of M15 decreased it by 19.7%.At low-to-middle mixing ratios （M15,M20,M30 and M50）,formaldehyde emissions showed a slight increase while those of high mixing ratios （M85 and M100） were three times compared with the baseline gasoline only.When the vehicles were retrofitted with new three-way catalytic converters （TWC）,emissions of carbon monoxide （CO）,total hydrocarbon （THC）,and nitrogen oxides （NOx） were decreased by 24%–50%,10%–35%,and 24%–58% respectively,compared with the cars using the original equipment manufacture （OEM） TWC.Using the new TWC,emissions of formaldehyde and BTEX were decreased,while those of other carbonyl increased.It is necessary that vehicles fueled with methanol/gasoline blends be retrofitted with a new TWC.In addition,the specific reactivity of emissions of vehicles fueled with M15 and retrofitted with the new TWC was reduced from 4.51 to 4.08 compared to the baseline vehicle.This indicates that the use of methanol/gasoline blend at a low mixing ratio may have lower effect on environment than gasoline.展开更多
According to advantages of neural network and characteristics of operatingprocedures of engine, a new strategy is represented on the control of fuel injection and ignitiontiming of gasoline engine based on improved BP...According to advantages of neural network and characteristics of operatingprocedures of engine, a new strategy is represented on the control of fuel injection and ignitiontiming of gasoline engine based on improved BP network algorithm. The optimum ignition advance angleand fuel injection pulse band of engine under different speed and load are tested for the samplestraining network, focusing on the study of the design method and procedure of BP neural network inengine injection and ignition control. The results show that artificial neural network technique canmeet the requirement of engine injection and ignition control. The method is feasible for improvingpower performance, economy and emission performances of gasoline engine.展开更多
A simulated gasoline consisting of model sulfur compounds of thiophene （C4H4S） and 3-methythiophene （3-MC4H4S） dissolved in n-heptane was tested for the oxidative desulfurization in the hydrogen peroxide （H202） ...A simulated gasoline consisting of model sulfur compounds of thiophene （C4H4S） and 3-methythiophene （3-MC4H4S） dissolved in n-heptane was tested for the oxidative desulfurization in the hydrogen peroxide （H202） and formic acid oxidative system over metal oxide-loaded molecular sieve. The effects of the oxidative system, loaded metal oxides, phase transfer catalyst, the addition of olefin and aromatics on sulfur removal were investigated in details. The results showed that the sulfur removal rate of simulated gasoline in the H202/formic acid system was higher than in other oxidative systems. The cerium oxide-loaded molecular sieve was found very active catalyst for oxidation of simulated gasoline in this system. The sulfur removal rates of C4H4S and 3-MC4H4S were enhanced when phase transfer catalyst （PTC） was added. However, the sulfur removal rate of simulated gasoline was reduced with the addition of olefin and aromatics.展开更多
The extractive desulfurization of a model gaso- line containing several alkyl thiols and aromatic thiophenic compounds was investigated using two imidazolium-based ionic liquids （ILs）, 1-butyl-3-methylimidazolium te...The extractive desulfurization of a model gaso- line containing several alkyl thiols and aromatic thiophenic compounds was investigated using two imidazolium-based ionic liquids （ILs）, 1-butyl-3-methylimidazolium tetrachloroaluminate, and 1-octyl-3-methylimidazolium te- trafluoroborate, as extractants. A fractional factorial design of experiments was employed to evaluate the effects and possible interactions of several process variables. Analysis of variance tests indicated that the number of extraction steps and the IL/gasoline volume ratio were of statistically highly significant, but none of the interactions were significant. The results showed that the desulfurization efficiency of the model gasoline by the ILs could reach 95.2 % under the optimal conditions. The optimized conditions were applied to study the extraction of thiophenic compounds in model gasoline and several real gasoline samples; the following order was observed in their separation： benzothio- phenc 〉 thiophcne 〉 3-methylthiophene 〉 2-methylthiophene, with 96.1% removal efficiency for benzothiophene. The IL extraction was successfully applied as a complementary process to the adsorptive desulfurization with acti- vated Raney nickel and acetonitrile solvent. The results indicated that the adsorptive process combined with IL extraction could provide high efficiency and selectivity, which can be regarded as a promising energy efficient desulfurization strategy for production of low-sulfur gasoline.展开更多
In this study, phosphorus modification by trimethyl phosphate impregnation was employed to enhance the hydrothermal stability of nano‐sized HZSM‐5 zeolites. A parallel modification was studied by ammonium dihydrogen...In this study, phosphorus modification by trimethyl phosphate impregnation was employed to enhance the hydrothermal stability of nano‐sized HZSM‐5 zeolites. A parallel modification was studied by ammonium dihydrogen phosphate impregnation. The modified zeolites were subjected to steam treatment at 800 °C for 4 h (100% steam) and employed as catalysts for olefin catalyticcracking (OCC) of full‐range fluid catalytic cracking (FCC) gasoline. X‐ray diffraction, N2 physicaladsorption and NH3 temperature‐programmed desorption analysis indicated that, although significantimprovements to the hydrothermal stability of nano‐sized HZSM‐5 zeolites can be observedwhen adopting both phosphorus modification strategies, impregnation with trimethyl phosphatedisplays further enhancement of the hydrothermal stability. This is because higher structural crystallinityis retained, larger specific surface areas/micropore volumes form, and there are greaternumbers of surface acid sites. Reaction experiments conducted using a fixed‐bed micro‐reactor(catalyst/oil ratio = 4, time on stream = 4 s) showed OCC of full‐range FCC gasoline-under a fluidized‐bed reaction mode configuration-to be a viable solution for the olefin problem of FCC gasoline.This reaction significantly decreased the olefin content in the full‐range FCC gasoline feed, andspecifically heavy‐end olefins, by converting the olefins into value‐added C2–C4 olefins and aromatics.At the same time, sulfide content of the gasoline decreased via a non‐hydrodesulfurization process.Nano‐sized HZSM‐5 zeolites modified with trimethyl phosphate exhibited enhanced catalytic performance for OCC of full‐range FCC gasoline.展开更多
To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exer...To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exergy balance model was built. The working processes of gasoline engine were simulated by using the GT-power. In this way, the required parameters were calculated and then gasoline engine exergy balance was obtained by programming on computer. On this basis, the influences of various parameters on exergy balance were analyzed. Results show that, the proportions of various forms of exergy in gasoline engine from high to low are irreversible loss, effective work, exhaust gas exergy and heat transfer exergy. Effective exergy proportion fluctuates with cylinder volumetric efficiency at full load, while it always increases with break mean effective pressure （BMEP） at part load. Exhaust gas exergy proportion is more sensitive to speed, and it increases with speed increasing except at the highest speed. The lower proportion of heat transfer exergy appears at high speed and high load. Irreversible loss is mainly influenced by load. At part load, higher BMEP results in lower proportion of irreversible loss; at full load, the proportion of irreversible loss changes little except at the highest speed.展开更多
The restriction on sulfur level in gasoline has been increasingly tightened. The U.S.Tier 22222 regulation requires a reduction from average 340ppm to 30ppm from 2004 to 2008. Recently significant progress has been ma...The restriction on sulfur level in gasoline has been increasingly tightened. The U.S.Tier 22222 regulation requires a reduction from average 340ppm to 30ppm from 2004 to 2008. Recently significant progress has been made in effective high sulfur removal, such as post treatment of FCC gasoline by selective hydrotreating, S Zorb sulfur removal technology, OATS process etc. The sulfur content of FCC gasoline can be deceased to less than 10ppm. With regard to gasoline pool composition in China, it is very important to look for effective desulfurization processes that are simple, straightforward, with less hydrogen consumption. Post-treatment of FCC gasoline is a preferred option. From the point of view of comprehensive utilization, alkylation, polymerization, isomerisation etc. can be added to desulfurization process to meet the requirement of ultra low sulfur, premium.展开更多
In this study,ammonia emissions characteristics of typical light-duty gasoline vehicles were obtained through laboratory vehicle bench test and combined with New European Driving Cycle(NEDC)condition and Worldwide Har...In this study,ammonia emissions characteristics of typical light-duty gasoline vehicles were obtained through laboratory vehicle bench test and combined with New European Driving Cycle(NEDC)condition and Worldwide Harmonized Light Vehicles Test Cycle(WLTC)condition.The influence of ambient temperature on ammonia emissions is mainly concentrated in the cold start stage.The influence of ambient temperature on ammonia emission is shown that the ammonia emissions of light-duty gasoline vehicles under ambient temperature conditions(14 and 23℃)are lower than those under low ambient temperature conditions(-7℃)and high ambient temperature conditions(35 and 40℃).The influence of TWC on ammonia emission is shown that ammonia is a by-product of the catalytic reduction reaction of conventional gas pollutants in the exhaust gas in the TWC.Under NEDC operating conditions and WLTC operating conditions,ammonia emissions after the catalyst are 45 times and 72 times that before the catalyst,respectively.In terms of ammonia emissions control strategy research,Pd/Rh combination can reduce NH3 formation more effectively than catalyst with a single Pd formula.Precise control of the engine’s air-fuel ratio and combination with the optimized matched precious metal ratio TWC can effectively reduce ammonia emissions.展开更多
A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with t...A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with their counterpart Co-impregnated zeolite-based catalysts.Successful transformation of solid raw materials to targeted zeolite was confirmed by XRD,SEM,STEM,and N2 physisorption analysis.An in-depth study of acidic strength and acidic site distribution was conducted by NH3-TPD and Py-IR spectroscopy.Acidic strength showed a pivotal role in defining product range.Co@S1,with the weakest acidic strength of silicalite-1 among three types of zeolites,evaded over-cracking of product and exhibited the highest gasoline and isoparaffin selectivity(≈70%and 30.7%,respectively).Moreover,the solvent-free raw material grinding route for zeolite synthesis accompanies several advantages like the elimination of production of wastewater,high product yield within confined crystallization space,and elimination of safety concerns regarding high pressure due to the absence of the solvent.Facileness and easiness of the solvent-free synthesis route together with promising catalytic performance strongly support its application on the industrial scale.展开更多
Light cycle oil(LCO) with high content of poly-aromatics was difficult to upgrade and convert,which had hindered upgrading fuel quality to meet with the standard of automotive diesel for the purpose of sustainable dev...Light cycle oil(LCO) with high content of poly-aromatics was difficult to upgrade and convert,which had hindered upgrading fuel quality to meet with the standard of automotive diesel for the purpose of sustainable development.The hydrocracking behaviors of typical aromatics in LCO of naphthalene and tetralin were investigated over NiMo and CoMo catalysts.Several characterization methods including N2-adsoprtion and desorption,ammonia temperature-programmed desorption(NH3-TPD),Pyridine infrared spectroscopy(Py-IR),CO infrared spectroscopy(CO-IR),Raman and X-ray photoelectron spectroscopy(XPS) were applied to determine the properties of different catalysts.The results showed that CoMo catalyst with high concentration of S-edges could hydrosaturate more naphthalene to tetralin but exhibit lower yield of high-value light aromatics(carbon numbers less than 10) than NiMo catalyst.NiMo catalyst with high concentration of Mo-edges also presented a higher selectivity of converting naphthalene into cyclanes than CoMo catalyst.Subsequently,the naphthalene and LCO hydrocracking performances were also investigated over different catalysts systems.The activity evaluation and kinetic analysis results showed that the naphthalene hydrocracking conversion and the yield of light aromatics for CoMo-AY/NiMo-AY grading catalysts were higher than NiMo-AY/CoMo-AY grading catalysts at same condition.A stepwise reaction principle was proposed to explain the high efficiency of CoMo-AY/NiMoAY grading catalysts.Finally,the LCO hydrocracking evaluation results confirmed that CoMo-AY/NiMoAY catalysts grading system with low carbon deposition and high stability could remain high percentage of active phases,which was more efficient to convert LCO to high-octane gasoline.展开更多
基金supported by the National Natural Science Foundation of China(22076176,22276106)the Natural Science Foundation of Shandong Province(ZR2021YQ14)+3 种基金the Innovation Ability Improvement Project for Technology-based Small-and Medium-sized Enterprises of Shandong Province(2022TSGC1345)Jiangsu Province Science and Technology Plan Special Fund(BZ2022053)Key Research and Development Program of Anhui Province(202104g01020006)the Fundamental Research Funds for the Central Universities(202141008)。
文摘Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is appealing to build catalysts with ceria—an irreplaceable"reducible"component in three-way converters—to help eliminate the soot particles trapped in cGPFs via O_(2)-assisted combustion.While research aiming at understanding how these recipes function has continued for more than two decades,a universal model elucidating the roles of different"active oxygen"species is yet to be realized.In this perspective,by critically assessing the reported data about gasoline soot catalytic combustion over ceria catalysts,it is suggested that ceria ignites soot through contributing its lattice oxygen,giving rise to a"hot ring"region at the periphery of soot-catalyst interface.During the"re-oxidation"semi-cycles,electrophilic superoxides and/or peroxides(O_(x)^(n-))are produced at the Ce^(3+)and oxygen vacancy sites enriched in this collar-like region,and then work as key reactive phases for soot deep oxidation.Based on this"O_(x)^(n-)assisted"Mars-van Krevelen mechanism,several guidelines for ceria catalyst designing are proposed,ending with a summary about where future opportunities and challenges may lie in developing efficient and practical cGPF catalysts.
基金supported by National Key Research & Development Program-Intergovernmental International Science and Technology Innovation Cooperation Project (2021YFE0112800)National Natural Science Foundation of China (Key Program: 62136003)+2 种基金National Natural Science Foundation of China (62073142)Fundamental Research Funds for the Central Universities (222202417006)Shanghai Al Lab
文摘The gasoline inline blending process has widely used real-time optimization techniques to achieve optimization objectives,such as minimizing the cost of production.However,the effectiveness of real-time optimization in gasoline blending relies on accurate blending models and is challenged by stochastic disturbances.Thus,we propose a real-time optimization algorithm based on the soft actor-critic(SAC)deep reinforcement learning strategy to optimize gasoline blending without relying on a single blending model and to be robust against disturbances.Our approach constructs the environment using nonlinear blending models and feedstocks with disturbances.The algorithm incorporates the Lagrange multiplier and path constraints in reward design to manage sparse product constraints.Carefully abstracted states facilitate algorithm convergence,and the normalized action vector in each optimization period allows the agent to generalize to some extent across different target production scenarios.Through these well-designed components,the algorithm based on the SAC outperforms real-time optimization methods based on either nonlinear or linear programming.It even demonstrates comparable performance with the time-horizon based real-time optimization method,which requires knowledge of uncertainty models,confirming its capability to handle uncertainty without accurate models.Our simulation illustrates a promising approach to free real-time optimization of the gasoline blending process from uncertainty models that are difficult to acquire in practice.
基金received funding support from the National Natural Science Foundation of China (No.52272342)the National Engineering Laboratory for Mobile Source Emission Control Technology,China (No.NELMS2018A17).
文摘Ground-level ozone contamination has been globally an urban air quality issue,particularly for China,which has recently made significant progress in purifying its sky.Unregulated exhaust emissions from motor vehicles,predominantly carbonyls and volatile organic compounds(VOCs),are among the leading contributors to ozone formation.In this chassislevel study,the unregulated emissions from five China-5 certified gasoline/CNG bi-fuel taxis,along with their ozone forming potential(OFP),were evaluated.It is found that carbonyls and VOCs were mainly emitted during the starting phase no matter the engine was cold or hot.Compared to gasoline,CNG fueling reduced VOCs emissions on a large scale,especially in the starting phase,but had elevated carbonyls.On a fleet average,CNG fueling derived 15%and 46%less OFP than gasoline in cold-and hot-start tests,respectively.VOCs contributed to over 90%of the total OFP of the exhaust.In terms of alleviating ground-level ozone contamination,CNG is a feasible alternative to gasoline on light-duty vehicles.
基金the financial support from the CNOOC CCUS Major Project(Project Number KJGG-2022-12-CCUS-030402).
文摘The selective production of gasoline from syngas is an important technology in the current stage of energy transformation and upgrading.The product distribution of traditional Fischer-Tropsch synthesis follows the Anderson-Schulz-Flory(ASF)distribution law,and breaking through the distribution limitations to produce more gasoline components depends largely on the design and development of high-performance catalysts.In this paper,the recent research progress of bifunctional catalysts for gasoline production from syngas with high selectivity is summarized.This includes core-shell structure catalyst,microporous zeolite supported catalyst,mesoporous zeolite supported catalyst,metal oxide-zeolite relay catalyst.Moreover,the reaction mechanisms are summarized.The future prospects of catalysts for the high-selectivity synthesis of gasoline from syngas is also discussed.The current review will provide insights into the bifunctional catalysts for one-step syngas conversion to gasoline.
基金supported by the National Natural Science Foundation of China with Grant No.12002334 for C.Z.,Zhejiang Provincial Natural Science Foundation(Grant No.LQ21A020004 for C.Z.)the Excellent Youth Natural Science Foundation of Zhejiang Province,National Science Foundation of Anhui Province(2108085QE226)+1 种基金China(No.LR21E060001 for L.Q.and C.Z.)C.Z.acknowledges the China Scholarship Council(No.202108330166)for providing him with a visiting scholarship at NUS,Singapore.
文摘Efficient and secure refueling within the vehicle refueling systems exhibits a close correlation with the issues concerning fuel backflow and gasoline evaporation.This paper investigates the transient flow behavior in fuel hose refilling and simplified tank fuel replenishment using the volume of fluid method.The numerical simulation is validated with the simplified hose refilling experiment and the evaporation simulation of Stefan tube.The effects of injection flow rate and injection directions have been discussed in the fuel hose refilling part.For both the experiment and simulation,the pressure at the end of the refueling pipe in the lower located nozzle case is 30%higher than that in the upper located nozzle case at a high flow rate,and the backflow phenomenon occurs at the lower filling mode.The fluid will directly flush into the first pipe elbow,changing the flow pattern from bubble flow to slug flow,which results in low-frequency and high-amplitude flowpressure fluctuations.Ahexane refueling system,consisting of a refueling pipe,fuel tank and a vapor return line,is analyzed,in which hexane evaporation is considered.At the early refueling period,a higher refueling rate will lead to more obvious splashing,which leads to a higher average mass of hexane vapor and pressure in the tank.Two optimized fuel tank designs are examined.The lower fuel tank filling port exhibits significantly lower vapor hexane in the fuel tank compared to the other design,resulting in a reduction of 200 Pa in the peak pressure in the tank,which contributes to a substantial reduction of gasoline loss during tank filling.
文摘In order to improve the steady and dynamic characteristic of the idle speed control and study the performance of the fuzzy control method for the idle speed control, a fuzzy control system is developed to control the idle speed of gasoline engine. The construction and working principle of the fuzzy controller are described, and the design procedure of the fuzzy controller is given in detail. The control parameters are determined by computer simulation. The simulation and experiments on the engine test bench show that the idle speed is controlled accurately both in stationary and in dynamic states, and the fuzzy control method is robust to the changes of engine parameters.
文摘Based on the introduction of the basic combustion concept of gasoline direct injection(GDI)engine and its operation under different operating conditions,HC emission mechanisms of the GDI en-gine are analyzed.And HC emission characteristics of the GDI engine are compared with the PFI en-gine via a comparison test based on the FTP-75 driving cycle.It can be concluded that the GDI engineis facing a big challenge in meeting the future's HC emission standard.Reasons for the higher HC e-missions of the GDI engine are discussed and the ways for HC emission control are given.
文摘To investigate the characteristics of the condensation in gasoline vapor condensation recovery,the condensation process of gasoline vapor with turbulent flow in a vertical tube is simulated based on the gas-liquid two-phase flow model.An effective diffusion coefficient is used to describe mass diffusion among the species of gasoline vapor.Several variables including temperature,pressure,liquid film thickness and the variation of the Nusselt number in the tube are simulated.The effects of the inlet-to-wall temperature difference and the Reynolds number on the condensation rate and the Nusselt number are obtained by modelling.The results show that heat transfer and condensation can be enhanced significantly by increasing the inlet Reynolds number.However,the increase in the inlet-to-wall temperature difference has little effect on the condensation rate.It is also found that the gasoline vapor condensation rate is influenced greatly by the mass transfer resistance.The comparison of results from the model with previous experiments shows a good agreement.
文摘The effect of olefins on formation of sulfur compounds in FCC gasoline was studied in a small-scale fixed fluidized bed （FFB） unit at temperatures ranging from 400℃ to 500℃, a weight hourly space velocity （WHSV） of 10 h-1, and a catalyst/oil ratio of 6. The results showed that C4--C6 olefins contained in the FCC gasoline could react with HzS to form predominantly thiophenes, alkyl-thiophenes as well as a fractional amount of thiols, while large molecular olefins such as heptene could react with hydrogen sulfide to form benzothiophenes. The amount of sulfur compounds formed at different tem- peratures over different catalysts were in proportion to the mass fractions of olefins in the feedstock, with the amount of sulfur compounds formed over REUSY catalyst exceeding those formed over the shape selective zeolite catalyst owing to the effect of catalyst performance and the impact of catalyst on the degree of olefin conversion. The amount of sulfur compounds generated and their increase reached a maximum at 450℃ and a minimum at 400℃ because of the influence of temperature on the thermodynamic and kinetic constants for formation of sulfur compound as well as on the olefin conversion degree. Based on the above-mentioned study, a reaction network and a model for prediction of sulfur compounds generated upon reaction of olefins in FCC gasoline with HES were established.
文摘In this paper, the effect of MMT on the induction period of unleaded motor gasoline was studied, the manganese concentration, storage period of MMT-blended gasoline and environmental variables such as temperature and radiation intensity were considered to be main factors affecting the induction period of gasoline,when MMT-blended gasoline was exposed to light. It is found from experiments that the addition of MMT can improve the induction period of gasoline that is shielded from light, and reduce the induction period remarkably,when the gasoline is exposed to light. However, the radiation intensity is proved to be the leading influencing factor among all the environmental variables investigated.
基金supported by the National Natural Science Foundation of China(No.50876013)
文摘Regulated and unregulated emissions from four passenger cars fueled with methanol/gasoline blends at different mixing ratios （M15,M20,M30,M50,M85 and M100） were tested over the New European Driving Cycle （NEDC）.Volatile organic compounds （VOCs） were sampled by Tenax TA and analyzed by thermal desorption-gas chromatograph/mass spectrometer （TD-GC/MS）.Carbonyls were trapped on dinitrophenylhydrazine （DNPH） cartridges and analyzed by high performance liquid chromatography （HPLC）.The results showed that total emissions of VOCs and BTEX （benzene,toluene,ethylbenzene,p,m,o-xylene） from all vehicles fueled with methanol/gasoline blends were lower than those from vehicles fueled with only gasoline.Compared to the baseline,the use of M85 decreased BTEX emissions by 97.4%,while the use of M15 decreased it by 19.7%.At low-to-middle mixing ratios （M15,M20,M30 and M50）,formaldehyde emissions showed a slight increase while those of high mixing ratios （M85 and M100） were three times compared with the baseline gasoline only.When the vehicles were retrofitted with new three-way catalytic converters （TWC）,emissions of carbon monoxide （CO）,total hydrocarbon （THC）,and nitrogen oxides （NOx） were decreased by 24%–50%,10%–35%,and 24%–58% respectively,compared with the cars using the original equipment manufacture （OEM） TWC.Using the new TWC,emissions of formaldehyde and BTEX were decreased,while those of other carbonyl increased.It is necessary that vehicles fueled with methanol/gasoline blends be retrofitted with a new TWC.In addition,the specific reactivity of emissions of vehicles fueled with M15 and retrofitted with the new TWC was reduced from 4.51 to 4.08 compared to the baseline vehicle.This indicates that the use of methanol/gasoline blend at a low mixing ratio may have lower effect on environment than gasoline.
文摘According to advantages of neural network and characteristics of operatingprocedures of engine, a new strategy is represented on the control of fuel injection and ignitiontiming of gasoline engine based on improved BP network algorithm. The optimum ignition advance angleand fuel injection pulse band of engine under different speed and load are tested for the samplestraining network, focusing on the study of the design method and procedure of BP neural network inengine injection and ignition control. The results show that artificial neural network technique canmeet the requirement of engine injection and ignition control. The method is feasible for improvingpower performance, economy and emission performances of gasoline engine.
基金Supported by the National Natural Science Foundation of China （No.20276015） and the Natural Science Foundation of Hebei Province （No.203364）.
文摘A simulated gasoline consisting of model sulfur compounds of thiophene （C4H4S） and 3-methythiophene （3-MC4H4S） dissolved in n-heptane was tested for the oxidative desulfurization in the hydrogen peroxide （H202） and formic acid oxidative system over metal oxide-loaded molecular sieve. The effects of the oxidative system, loaded metal oxides, phase transfer catalyst, the addition of olefin and aromatics on sulfur removal were investigated in details. The results showed that the sulfur removal rate of simulated gasoline in the H202/formic acid system was higher than in other oxidative systems. The cerium oxide-loaded molecular sieve was found very active catalyst for oxidation of simulated gasoline in this system. The sulfur removal rates of C4H4S and 3-MC4H4S were enhanced when phase transfer catalyst （PTC） was added. However, the sulfur removal rate of simulated gasoline was reduced with the addition of olefin and aromatics.
基金National Iranian Oil Refining & Distribution Company(NIORDC) and Research & Development (R&D) center of this company for their financial support during the completion of this work
文摘The extractive desulfurization of a model gaso- line containing several alkyl thiols and aromatic thiophenic compounds was investigated using two imidazolium-based ionic liquids （ILs）, 1-butyl-3-methylimidazolium tetrachloroaluminate, and 1-octyl-3-methylimidazolium te- trafluoroborate, as extractants. A fractional factorial design of experiments was employed to evaluate the effects and possible interactions of several process variables. Analysis of variance tests indicated that the number of extraction steps and the IL/gasoline volume ratio were of statistically highly significant, but none of the interactions were significant. The results showed that the desulfurization efficiency of the model gasoline by the ILs could reach 95.2 % under the optimal conditions. The optimized conditions were applied to study the extraction of thiophenic compounds in model gasoline and several real gasoline samples; the following order was observed in their separation： benzothio- phenc 〉 thiophcne 〉 3-methylthiophene 〉 2-methylthiophene, with 96.1% removal efficiency for benzothiophene. The IL extraction was successfully applied as a complementary process to the adsorptive desulfurization with acti- vated Raney nickel and acetonitrile solvent. The results indicated that the adsorptive process combined with IL extraction could provide high efficiency and selectivity, which can be regarded as a promising energy efficient desulfurization strategy for production of low-sulfur gasoline.
基金supported by the National Natural Science Foundation of China (21603023)the Petro China Innovation Foundation, China (2014D-5006-0501)~~
文摘In this study, phosphorus modification by trimethyl phosphate impregnation was employed to enhance the hydrothermal stability of nano‐sized HZSM‐5 zeolites. A parallel modification was studied by ammonium dihydrogen phosphate impregnation. The modified zeolites were subjected to steam treatment at 800 °C for 4 h (100% steam) and employed as catalysts for olefin catalyticcracking (OCC) of full‐range fluid catalytic cracking (FCC) gasoline. X‐ray diffraction, N2 physicaladsorption and NH3 temperature‐programmed desorption analysis indicated that, although significantimprovements to the hydrothermal stability of nano‐sized HZSM‐5 zeolites can be observedwhen adopting both phosphorus modification strategies, impregnation with trimethyl phosphatedisplays further enhancement of the hydrothermal stability. This is because higher structural crystallinityis retained, larger specific surface areas/micropore volumes form, and there are greaternumbers of surface acid sites. Reaction experiments conducted using a fixed‐bed micro‐reactor(catalyst/oil ratio = 4, time on stream = 4 s) showed OCC of full‐range FCC gasoline-under a fluidized‐bed reaction mode configuration-to be a viable solution for the olefin problem of FCC gasoline.This reaction significantly decreased the olefin content in the full‐range FCC gasoline feed, andspecifically heavy‐end olefins, by converting the olefins into value‐added C2–C4 olefins and aromatics.At the same time, sulfide content of the gasoline decreased via a non‐hydrodesulfurization process.Nano‐sized HZSM‐5 zeolites modified with trimethyl phosphate exhibited enhanced catalytic performance for OCC of full‐range FCC gasoline.
基金Foundation item： Project（2011CB707201） supported by the National Basic Research Program of China Project（10JJ5058） supported by the Natural Science Foundation of Hunan Province, China
文摘To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exergy balance model was built. The working processes of gasoline engine were simulated by using the GT-power. In this way, the required parameters were calculated and then gasoline engine exergy balance was obtained by programming on computer. On this basis, the influences of various parameters on exergy balance were analyzed. Results show that, the proportions of various forms of exergy in gasoline engine from high to low are irreversible loss, effective work, exhaust gas exergy and heat transfer exergy. Effective exergy proportion fluctuates with cylinder volumetric efficiency at full load, while it always increases with break mean effective pressure （BMEP） at part load. Exhaust gas exergy proportion is more sensitive to speed, and it increases with speed increasing except at the highest speed. The lower proportion of heat transfer exergy appears at high speed and high load. Irreversible loss is mainly influenced by load. At part load, higher BMEP results in lower proportion of irreversible loss; at full load, the proportion of irreversible loss changes little except at the highest speed.
文摘The restriction on sulfur level in gasoline has been increasingly tightened. The U.S.Tier 22222 regulation requires a reduction from average 340ppm to 30ppm from 2004 to 2008. Recently significant progress has been made in effective high sulfur removal, such as post treatment of FCC gasoline by selective hydrotreating, S Zorb sulfur removal technology, OATS process etc. The sulfur content of FCC gasoline can be deceased to less than 10ppm. With regard to gasoline pool composition in China, it is very important to look for effective desulfurization processes that are simple, straightforward, with less hydrogen consumption. Post-treatment of FCC gasoline is a preferred option. From the point of view of comprehensive utilization, alkylation, polymerization, isomerisation etc. can be added to desulfurization process to meet the requirement of ultra low sulfur, premium.
基金supported by the National Natural Science Foundation of China(Nos.51508304 and 41275133)。
文摘In this study,ammonia emissions characteristics of typical light-duty gasoline vehicles were obtained through laboratory vehicle bench test and combined with New European Driving Cycle(NEDC)condition and Worldwide Harmonized Light Vehicles Test Cycle(WLTC)condition.The influence of ambient temperature on ammonia emissions is mainly concentrated in the cold start stage.The influence of ambient temperature on ammonia emission is shown that the ammonia emissions of light-duty gasoline vehicles under ambient temperature conditions(14 and 23℃)are lower than those under low ambient temperature conditions(-7℃)and high ambient temperature conditions(35 and 40℃).The influence of TWC on ammonia emission is shown that ammonia is a by-product of the catalytic reduction reaction of conventional gas pollutants in the exhaust gas in the TWC.Under NEDC operating conditions and WLTC operating conditions,ammonia emissions after the catalyst are 45 times and 72 times that before the catalyst,respectively.In terms of ammonia emissions control strategy research,Pd/Rh combination can reduce NH3 formation more effectively than catalyst with a single Pd formula.Precise control of the engine’s air-fuel ratio and combination with the optimized matched precious metal ratio TWC can effectively reduce ammonia emissions.
基金the financial support from the Zhejiang Province Natural Science Foundation(LY19B060001)the Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering(2018-K25)the Foundation of Zhejiang University of Science and Technology(2019QN18,2019QN23)~~
文摘A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with their counterpart Co-impregnated zeolite-based catalysts.Successful transformation of solid raw materials to targeted zeolite was confirmed by XRD,SEM,STEM,and N2 physisorption analysis.An in-depth study of acidic strength and acidic site distribution was conducted by NH3-TPD and Py-IR spectroscopy.Acidic strength showed a pivotal role in defining product range.Co@S1,with the weakest acidic strength of silicalite-1 among three types of zeolites,evaded over-cracking of product and exhibited the highest gasoline and isoparaffin selectivity(≈70%and 30.7%,respectively).Moreover,the solvent-free raw material grinding route for zeolite synthesis accompanies several advantages like the elimination of production of wastewater,high product yield within confined crystallization space,and elimination of safety concerns regarding high pressure due to the absence of the solvent.Facileness and easiness of the solvent-free synthesis route together with promising catalytic performance strongly support its application on the industrial scale.
基金supported by the National Natural Science Foundation of China (Nos. 21878330, 21676298)the National Science and Technology Major Project, the CNPC Key Research Project (2016E-0707)the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award (No. OSR-2019-CPF-4103.2)。
文摘Light cycle oil(LCO) with high content of poly-aromatics was difficult to upgrade and convert,which had hindered upgrading fuel quality to meet with the standard of automotive diesel for the purpose of sustainable development.The hydrocracking behaviors of typical aromatics in LCO of naphthalene and tetralin were investigated over NiMo and CoMo catalysts.Several characterization methods including N2-adsoprtion and desorption,ammonia temperature-programmed desorption(NH3-TPD),Pyridine infrared spectroscopy(Py-IR),CO infrared spectroscopy(CO-IR),Raman and X-ray photoelectron spectroscopy(XPS) were applied to determine the properties of different catalysts.The results showed that CoMo catalyst with high concentration of S-edges could hydrosaturate more naphthalene to tetralin but exhibit lower yield of high-value light aromatics(carbon numbers less than 10) than NiMo catalyst.NiMo catalyst with high concentration of Mo-edges also presented a higher selectivity of converting naphthalene into cyclanes than CoMo catalyst.Subsequently,the naphthalene and LCO hydrocracking performances were also investigated over different catalysts systems.The activity evaluation and kinetic analysis results showed that the naphthalene hydrocracking conversion and the yield of light aromatics for CoMo-AY/NiMo-AY grading catalysts were higher than NiMo-AY/CoMo-AY grading catalysts at same condition.A stepwise reaction principle was proposed to explain the high efficiency of CoMo-AY/NiMoAY grading catalysts.Finally,the LCO hydrocracking evaluation results confirmed that CoMo-AY/NiMoAY catalysts grading system with low carbon deposition and high stability could remain high percentage of active phases,which was more efficient to convert LCO to high-octane gasoline.
