Low Temperature Combustion Research Articles

Machine learning approaches for identification of heat release shapes in a low temperature combustion engine for control applications

This paper presents the application of machine learning classification algorithms to identify and classify different heat release rate (HRR) shapes to control the combustion for an optimal multi-mode low-temperature combustion (LTC) engine operation. Low-temperature combustion engine produces low nitrogen oxides (NOx) and soot emissions and offers high thermal efficiency. But high in-cylinder pressure rise rates limit the operating range of the LTC engine. Therefore, it is imperative to control combustion in the LTC engine for safe operation. To this end, the HRR traces for over six hundred engine operating conditions are classified using supervised (i.e., Decision Tree, K-Nearest Neighbors (KNN), and Support Vector Machines (SVM)) and unsupervised (i.e., Kmeans clustering) machine learning approaches to segregate different combustion regimes based on HRR shape. Kmeans clustering was not successful in classifying the HRR shapes. Among different supervised machine learning techniques, SVM has proved to be the best method, having an overall classifier prediction accuracy of 92.4% for identifying the distinct shapes using normalized HRR data. In addition, three classifiers have been trained based on the combustion parameters and control inputs. These classifiers are then used as scheduling variables to develop predictive models. A model predictive control (MPC) framework is developed to control multi-mode LTC engine on cycle-to-cycle basis. The MPC framework achieved the simultaneous reference tracking of combustion phasing (CA50) and indicated mean effective pressure (IMEP) while constraining maximum pressure rise rate (MPRR) below 8 bar/CAD.

Study on the Effect of High-Concentration Oxygen Enrichment on Engine Performance and Exhaust Emissions Using Diesel Fuel and Palm Biodiesel Substitute Fuel

Air pollution remains a big issue in many countries. One form of air pollution comes from the use of fossil fuels as the primary fuel in the power generating and transportation sectors. Diesel engines are employed in a variety of industries due to their dependability, durability, and efficiency. Enhancing the availability of oxygen within the combustion chamber is one technique for reducing exhaust gas emissions and optimizing diesel engine combustion. The aim of this study is to investigate how oxygen enrichment in diesel engines with diesel fuel and biodiesel affects their performance and emissions. The modeling in this research was carried out using AVL BOOST version 2011 software based on experimental results of the YANMAR TF 155 R-DI diesel engine at 1200 rpm with and without oxygen enrichment. Modeling was performed based on the baseline parameter of a diesel engine with gradual loads at 50%, 75%, and 100%. The oxygen concentration was increased to 30.6%, 37.8%, 45%, and 54% by mass. The results show an increase in the maximum heat release rate (HRR) and the mass fraction burned (MFB) up to 90% for both fuels. The peak heat release rate of biodiesel shifts around 6 J/degree and the brake-specific fuel consumption (BSFC) is up to 0.0035 kg/kWh higher than that of diesel fuel. When compared to diesel fuel, the thermal efficiency and BSFC of biodiesel usage are around 0.3% and 0.028 kg/kWh, respectively. NOx emissions increase due to higher combustion temperatures and more oxygen availability. Biodiesel emits 50% less NOx than diesel fuel, presumably due to a lower combustion temperature. As a result, while high-concentration oxygen enrichment improves combustion and lowers soot emissions, it raises NOx emissions. Soot emissions were reduced as a result of the enhanced combustion process, while NOx emissions rose due to higher combustion temperatures and increased oxygen availability.

Optical investigation of low temperature combustion and soot emission characteristics of biodiesel/n-pentanol engine

Biodiesel/n-pentanol blend fuels have been regarded as the attractive alternatives for the utilization of diesel engines. However, the fundamental studies of low temperature combustion and soot formation characteristics of biodiesel/n-pentanol blend fuels in diesel engines are still scarce. The low temperature combustion and soot emission characteristics of pure waste cooking oil (WCO) biodiesel (B100) and 70% WCO biodiesel/30% n-pentanol blend (B70P30) were experimentally studied in an optical engine in the present study. Results reveal that B70P30 has longer ignition delays than B100 at low exhaust gas recirculation (EGR) rate, but the ignition delays of B70P30 become similar or even shorter when the EGR rate is over 12%. Adding n-pentanol into biodiesel increases the in-cylinder combustion pressure peak and maximum pressure rise rate. In addition, the delay in the appearance of ignition kernels and two-color images are observed for B70P30 fuel. In the initial stage of fuel combustion, B70P30 has less ignition kernels and lower soot KL factor distribution area. In the middle and late stages of combustion, flame area of B70P30 is small and flame brightness is weaker. Also, at the end of combustion, the two-color images of B70P30 show that the soot KL factor distribution around the periphery of the chamber is decreasing at a higher rate compare to B100.

Engineering the core–shell structure CoMnOx@OTS cubic catalyst with excellent water resistance for low-temperature catalytic combustion of VOCs

Engineering the core–shell structure CoMnO_<i>x</i>@OTS cubic catalyst with excellent water resistance for low-temperature catalytic combustion of VOCs

Experimental investigation of low temperature combustion in a diesel engine depending on injection advance and injection pressure

In this study, the performance parameters and emissions of a pre-mixed charge compression ignition were investigated under different injection pressures and injection advances. After the peak engine power was reached, reasonable decreases occurred in brake mean effective pressure at certain injection advances with the increase of injection advance, and dramatic decreases observed when interval was so exceeded. In addition mean indicated pressure and peak in-cylinder pressure were investigated. Considering the emissions, dramatic increases were observed in CO and total hydrocarbon, depending on the increase in the low temperature combustion regime. The NOx started a rapid downward trend after a certain injection advance value in the experimental region, but this effect did not occur at the de?sired level for specific NOx. It was observed that the NO2 to NOx ratio increased as the pre-mixed charge compression ignition became dominant and NO2 production increased among the total NOx. In the operating region where the low temperature combustion regime was dominant, the targeted reduction in NOx and particulate matter emissions was observed, but the desired reduction in specific emissions did not occur. In the low temperature combustion region, the combustion process was prolonged, initially reasonable changes occurred at performance parameters, but unacceptable results were observed at high injection pressures with excessive injection advances.

Термодинамическое моделирование высокоэнергетических термитных систем на основе йодата кальция

The article presents the results of a thermodynamic study of the component content influence and their physical and chemical properties on the regulation of the main energy characteristics and combustion product characteristics of thermite systems based on calcium iodate containing Al, B and Ti. The adiabatic combustion temperature, enthalpy of combustion products, specific impulse, exhaust velocity of combustion products, mass fraction of condensed phases, content of gaseous and condensed combustion products are determined. The influence of the metal oxide/metal fuel content in the thermite system composition on the main energy characteristics was assessed. Based on a comparison of the calculation results of the thermite systems thermodynamic and thermophysical characteristics, it seems possible to divide the studied thermite systems into 3 functional groups according to their application. Taking into account the ratio of components, these can be: 1) thermite systems for welding processes and 2) thermite systems for perforating, cutting metal structures (CaI2O6/Al and CaI2O6/Ti); 3) thermite systems as a component of energy compositions capable to inactivate harmful aerosol spores and bacteria (CaI2O6/B), since due to the low combustion temperature of CaI2O6/B, a longer burning time of such systems leads to a gradual release of iodine.

Probing O2-dependence of cyclopentyl reactions via isomer-resolved speciation

Modeling chemical kinetics relevant to low-temperature combustion requires complete description of reactions involving critical species such as hydroperoxyalkyl radicals, Q˙OOH, which undergo competing unimolecular reactions and bimolecular reactions with O2. The balance of flux across the two pathways affects rates of chain-branching and depends on temperature, pressure, and oxygen concentration. Accordingly, the influence of [O2] on product formation from alkyl + O2 reactions and the subsequent fate of Q˙OOH and related products is central to the development of an accurate chemical kinetics mechanism. However, chemical reactions consuming Q˙OOH-mediated species are often simplified to such a degree that mechanism truncation error (uncertainty derived from incomplete reaction networks) becomes significant.For the specific purpose of determining the extent to which expanded sub-mechanisms ameliorate inaccuracies in model predictions resulting from mechanism truncation error, the present work integrates speciation measurements from jet-stirred reactor experiments on cyclopentane oxidation with modeling using an expanded detailed chemical kinetics mechanism. The experiments utilize vacuum ultraviolet-absorption spectroscopy and mass spectrometry for isomer-resolved speciation of intermediates produced from cyclopentane oxidation at 835 Torr from 500 – 1000 K. [O2]-dependent experiments were also conducted from 0.12 – 3.66 · 1018 molecules cm–3 at 825 K to examine the influence on species profiles. The expanded mechanism is produced by merging detailed sub-mechanisms for Q˙OOH-mediated species (cyclopentene and 1,2-epoxycyclopentane) produced using Reaction Mechanism Generator (RMG) with an existing detailed mechanism for cyclopentane.Model predictions using the expanded mechanism yielded improvements in species mole fractions for both temperature- and O2-dependence. Ignition delay time simulations were also conducted and show appreciable sensitivity in the negative-temperature coefficient region due to incorporation of the detailed sub-mechanisms due to influence on O˙H radical populations. Sensitivity analysis revealed reactions that merit theoretical rate calculations for additional improvements and include species such as H2O2 and species related to R˙ + O2 reactions of cyclopentene and 1,2-epoxycyclopentane.

Design and Experimental Study of Hydrogen Elimination Device for Pd / Pt Exhaust Gas of Proton Exchange Membrane Fuel Cell

This study addresses incomplete hydrogen emissions from hydrogen fuel cell exhausts, focusing on developing safe, efficient strategies to reduce residual hydrogen levels, ensuring compliance with strict environmental and safety norms. Despite maximizing hydrogen utilization, fuel cells inevitably emit residual hydrogen, posing safety risks. An innovative exhaust hydrogen eliminator design is proposed, examining the efficacy of a palladium/platinum catalyst in enhancing hydrogen removal via catalytic combustion. Through systematic investigation on a specialized test platform, factors like airflow, temperature, pressure, and hydrogen concentration influenced the catalytic hydrogen eliminator’s performance. Results highlight the palladium/platinum catalyst’s impact on hydrogen conversion, notably superior platinum performance over palladium, achieving maximum elimination rates of 61% and 96%, respectively. Catalyst shell temperature correlated with input hydrogen concentration, stabilizing near 102°C at 1.97% hydrogen, indicating stable catalytic reactions under tested conditions, pivotal for low-temperature combustion within the hydrogen eliminator.

Study on lean combustion of ammonia-hydrogen mixtures in a pre-chamber engine

Ammonia holds promise for achieving zero carbon emissions from internal combustion engines. The pre-chamber turbulent jet ignition, characterized by multipoint distributed ignition and rapid combustion, could be applied to ammonia combustion to extend combustion limits and stability. This study investigates the impacts of hydrogen energy fraction (Hfrac), equivalence ratio, and ignition timing on the combustion and emission characteristics of ammonia-hydrogen mixture at lean combustion conditions in a pre-chamber (PC) marine engine by CFD Simulation. In H2-fuel active PC mode, increasing the hydrogen content or achieving stoichiometric combustion within the PC will shorten the cold jet phase and accelerate the formation of a more intense hot jet. As the Hfrac and the equivalence ratio in the main-chamber increase, the combustion pressure, temperature, and heat release rate (HRR) rise, while the combustion duration shortens due to enhanced reactivity, potentially leading to end gas auto-ignition and knock due to lower auto-ignition energy of the mixture. NO primarily forms near the flame front, and both NO concentration and the generation area increase with an increase in hydrogen content and equivalence ratio. Fuel-NO is likely to be the dominant factor in NO generation with lean combustion conditions. N2O, as a product of NH3 low-temperature combustion, is mainly concentrated near the flame front. An increase in unburned NH3 emissions corresponds to an increase in N2O emissions. Delaying the ignition timing to reduce NOx emissions is primarily achieved by controlling NO emissions, even though there is a slight increase in N2O.

Uniformly Dispersed Nano Pd-Ni Oxide Supported on Polyporous CeO2 and Its Application in Methane Conversion of Tail Gas from Dual-Fuel Engine

The development of catalysts for low-temperature methane combustion is crucial in addressing the greenhouse effect. An effective industrial catalyst strategy involves optimizing noble metal utilization and boosting metal–metal interaction. Here, the PdNi-H catalyst was synthesized using the self-assembly method, achieving the high dispersion and close proximity of Pd and Ni atoms compared to the counterparts prepared by the impregnation method, as confirmed by EDS mapping. The XRD and TEM results revealed Pd2+ and Ni2+ doping within the CeO2 lattice, causing distortions and forming Pd-O-Ce or Ni-O-Ce structures. These structures promoted oxygen vacancy formation in CeO2, and this was further confirmed by the Raman and XPS results. Consequently, the PdNi-H catalyst demonstrated an excellent redox ability and catalytic activity, achieving lower ignition and complete methane burning temperatures at 282 and 387 °C, respectively. The highly dispersed PdNi species played a pivotal role in activating methane for enhanced redox ability. Additionally, the narrow size distribution range contributed to more vacancies on the surface of CeO2, as confirmed by the XPS results, thereby facilitating the activation of gas phase oxygen to form oxygen species (O2−). This collaborative catalytic approach presents a promising strategy for developing efficient and stable methane combustion catalysts at low temperatures.

Исследование параметров горения жидкого углеводородного топлива при его распылении перегретым водяным паром, углекислым газом и их смесью

Reducing the anthropogenic impact on the environment is one of the priority tasks of our time. One of the sources of pollution is the burial of a large amount of substandard combustible waste, including hydrocarbon waste, which is not currently in demand, as well as solid and toxic substances generated during combustion. The solution to the identified problems is possible through the Waste-to-Energy approach, aimed at involving combustible waste in the fuel balance, with the organization of low-temperature combustion by adding various diluent gases - carbon dioxide or water vapor. In this work, using diesel fuel as an example, the combustion characteristics of liquid hydrocarbons in the presence of a mixture of superheated steam and carbon dioxide in a spray burner were experimentally obtained and compared to identify the features and advantages of their use in Waste-to-Energy approaches. It is shown that for all studied modes a high completeness of fuel combustion is observed. Analysis of the composition of combustion pro¬ducts shows that when replacing superheated steam with carbon dioxide, the content of CO and NOx in combustion products increases by 25%. At the same time, all studied modes comply with the EN:267 standard. The results show that it is possible to implement approaches of adding carbon dioxide, water vapor and a mixture of both to convert waste into energy.

Fuel control strategy for robust low-load gasoline low temperature combustion

To achieve robust low-load LTC (Low Temperature combustion), precise metering of fuel is required since the combustion is very sensitive to the variation of the injected fuel quantity, which could range from 1 to 3 mg per injection pulse. Open-loop calibration of individual injectors is simply not a practical option and therefore a fuel control strategy has been developed to ensure robust low-load LTC combustion and validated through experiments on a 2.2 L 4-cylinder LTC engine at two different coolant temperatures. The results show that the fuel control strategy significantly improves low-load LTC combustion stability by reducing cylinder-to-cylinder variation in delivered fuel masses due to different injector characteristics even when engine operating conditions are changed.

Experimental investigation of the effect of ammonia substitution ratio on an ammonia-diesel dual-fuel engine performance

This research experimentally examines an ammonia-diesel dual fuel system, not widely covered in existing literature but acknowledged as an effective approach to reduce engine carbon footprints in alignment with global decarbonization trends, focusing on enhancing understanding of performance, combustion, and emission characteristics vital for designing and optimizing these engines for commercialization. The results indicate that in an ammonia-air mixture atmosphere, diesel undergoes a prolonged ignition process, enhancing the role of premixed combustion. Increasing ammonia substitution at constant speed and load reduces the weight of mixing-controlled combustion, leading to larger areas in the chamber where diesel flames cannot reach. Ammonia oxidation mainly occurs near the diesel flame, as overly lean ammonia-air mixtures fail to sustain stable flame propagation. This results in considerable unburned ammonia emissions, particularly in regions beyond diesel flame reach and engine crevices, adversely affecting combustion efficiency and diminishing the thermal efficiency advantages of such operation. Furthermore, while ammonia combustion contributes to fuel-borne nitrogen oxides (NOx) formation, the overall NOx emissions from ammonia-diesel engines are reduced due to lower combustion temperatures and the deNOx properties of amino groups. However, the partial oxidation of ammonia during the late expansion stroke generates significant levels of nitrous oxide (N2O), a greenhouse gas, in the emissions, counteracting the intended reduction of carbon dioxide. These experimental findings highlight the necessity of focusing on both improving in-cylinder combustion quality and developing effective aftertreatment systems for NH3 and N2O capture, as crucial steps towards enhancing the environmental performance and market viability of ammonia-diesel dual fuel engines.

Frictional Losses of Ring Pack in SI and HCCI Engine

The vast majority of research dedicated to enhancing the homogenous charge compression ignition (HCCI) low-temperature combustion system is focused on improving controllability, efficiency and emissions. This article aims to assess the impact of HCCI combustion on the operation of the piston ring system. Utilizing the measured pressures in the combustion chamber of a single-cylinder research engine operating in spark ignition (SI) and HCCI modes at various loads, simulations were carried out using an advanced ring pack model. This model integrates the gas flow, ring dynamics and ring mixed lubrication models. Simulations revealed that differences in the pressure above the piston between the HCCI and SI combustion significantly influence ring pack performance. The predicted energy losses due to the friction of piston rings against the cylinder liner are up to 5% higher in the HCCI engine than in the SI engine. This identified drawback diminishes the advantages of the HCCI engine resulting from higher thermal efficiency, and efforts should be made to minimize this negative impact.

Local Electron Environment Regulation of Spinel CoMn2O4 Induced Effective Reactant Adsorption and Transformation of Lattice Oxygen for Toluene Oxidation.

In contrast to numerous studies on oxygen species, the interaction of volatile organic compounds (VOCs) with oxides is also critical to the catalytic reaction but has hardly been considered. Herein, we develop a highly efficient Pt atom doped spinel CoMn2O4 (Pt-CoMn) for oxidation of toluene at low temperature, and the toluene conversion rate increased by 18.3 times (129.7 versus 7.1 × 10-11 mol/(m2·s)) at 160 °C compared to that of CoMn2O4. Detailed characterizations and density functional theory calculations reveal that the local electron environment of the Co sites is changed after Pt doping, and the formed electron-deficient Co sites in turn strengthen the interaction with toluene. Adsorbed toluene will react with lattice oxygen in Pt-CoMn and CoMn catalysts and convert into benzoate intermediates, and the consumption rate of benzoate is closely related to the activation of gaseous oxygen. Significantly, the abundant bulk defects of Pt-CoMn help to open the reaction channel in the CoMn spinel, which acts as an oxygen pump to promote the transformation of bulk lattice oxygen into surface lattice oxygen at lower temperatures, thus accelerating the conversion rate of benzoate intermediates into CO2 and enhancing low-temperature combustion of toluene. Pt-CoMn developed here emphasizes the regulation of VOCs adsorption strength and lattice oxygen transformation processes on CoMn2O4 by adjusting the local electron environment, which will provide new guidance for the design of efficient oxide catalysts for catalytic oxidation.

The relationship between fuel reactivity and exergy features in combustion process

Fuel reactivity is a flexible and feasible method to control combustion, thus reactivity-controlled compression ignition (RCCI) has the potential to achieve lower emissions and higher thermal efficiency. However, the exergy loss during combustion hinders the further exergy-work transform, which limits the thermal efficiency further improvement. The present work focuses on the relationship between fuel reactivity and exergy which contains exergy loss (EL) and thermomechanical exergy (Exthermo due to the temperature and pressure imbalance between system and reference state). By varying the reactivity of primary reference fuels (PRFs) with different initial boundary conditions, it is found that different PRFs could not reduce EL and change Exthermo under same condition but could change the exergy loss rate as well as the EL structure by influencing low-temperature combustion. In terms of boundary conditions, both high temperature and lean mixture could improve Exthermo but with different mechanism: high temperature saving EL into Exthermo, lean mixture recovering incomplete combustion exergy (Exincom) into Exthermo. By contrast, equivalence ratio more easily affects EL and Exthermo. In three-dimensional situation, it is found that decreasing reactivity of PRFs leads more in-cylinder area below equivalence ratio 1.0 which benefits for the Exthermo improvement, but it would cause Exthermo structure mutation which is unfriendly for the smooth output of work near top dead center. The conversion of fuel exergy to final useful work is indirect, and there exist two sub-processes: fuel exergy to thermomechanical exergy then thermomechanical exergy to useful work. The final exergy-work transform efficiency is influenced by both processes. Therefore, using low reactivity fuel as PRF90 in engine is favor of the exergy from fuel transforming into Exthermo by more lean mixture, adopting high reactivity fuel as PRF0 is favor of the Exthermo sequential structure which is benefit for the combustion control and useful work extract near top dead center. Therefore, there is potential to further improve the thermal efficiency by using a dual-fuel combination, with the low reactivity fuel creating a low equivalence ratio region to improve the thermomechanical exergy, and the high reactivity fuel achieving precise phase control during the combustion.

Analysis of the Vibrational Behavior of dual-fuel RCCI combustion in a Heavy-Duty Compression Ignited Engine fueled with Diesel-NG at Low Load

In the field of internal combustion engines, the Low Temperature Combustions (LTC) appear to have the potential to reduce the formation of both soot and nitrogen oxides. One of the most promising LTC is Reactivity Controlled Compression Ignition (RCCI) which is based on the combustion of a lean low reactivity fuel-air mixture generated in the intake manifold and autoignited by small injections of high reactivity fuel introduced at high pressure in the combustion chamber. By the combination of net-zero natural gas and biodiesel, such LTC methodology might represent a suitable solution moving toward zero-emissions in transportation sector.Despite the potential to reduce pollutant emissions, Low Temperature Combustion strategies face a challenge in controlling the angular position where the combustion takes place which can be overcome by a proper management of the high-pressure injections.One potentially interesting application is related to trucks, mainly because they have long periods of idling, since emissions can be drastically reduced by means LTC. A single cylinder research engine for heavy duty application is operated under steady state conditions at low load and speed to analyze the possibility of controlling the engine behavior in dual fuel RCCI mode. The results indicate that the combustion mode switches from the dual-stage to gaussian within a narrow angular range. A further advance of the start of injection can generate misfires and significant variations in typical combustion indexes, while a delayed start of injection can cause impulsive combustion that rises the cylinder temperature and results in high-frequency pressure oscillations inside the combustion chamber. These oscillations are related to the combustion chamber typical resonance frequency, and if relevant in amplitude and persist for a long time, they might generate a potential source of failures.

A Numerical Investigation on Laminar Flame Speed of Syngas in Air with Ozone Addition

In the context of energy and propulsion systems, in recent years engineering research has increased its efforts to develop more efficient technologies with a lower environmental impact. Specifically, new combustion systems have been investigated, such as ultra-lean combustion and Homogeneous Charge Compression Ignition (HCCI) combustion, and sustainable fuels have been employed. With respect to the latter option, syngas and hydrogen have emerged as attractive choices. However, the low specific energy of syngas and the presence of diluents can cause flame failure and instability. On the other hand, it is well known that ozone-assisted combustion enhances the Laminar Flame Speed (LFS), reduces the ignition delay time, and improves the flame stabilization of fuels such as methane, n-heptane and iso-octane, since it affects the chemistry in the Low Temperature Combustion (LTC) regime. In this context, the aim of the present work is to evaluate the effect of ozone on the LFS of syngas/ozone/air mixtures. Specifically, 1-D simulations have been carried out to compute the LFS of CO/H2 and CO/H2/N2 syngas mixtures. The model has been validated against experimental data available in the scientific literature by considering four different reaction mechanisms. Then, the model has been used to perform a parametric analysis by considering different conditions in terms of syngas composition (three different CO/H2 ratios) and equivalence ratio (from 0.5 to 5). The results show that the addition of 2500 ppm of ozone in air results in an increase in LFS for all equivalence ratios examined. The four different mechanisms give comparable results in terms of LFS and LFS increase for CO/H2 syngas, and are also able to predict ozone effect on LFS enhancement for CO/H2/N2 mixtures. Finally, the results show that the influence of ozone, in terms of LFS percentage increase, is greater for CO/H2 ultra lean mixtures with a lower CO/H2 ratio.

Hydrogenation of CO2 on Co–Ni Catalysts Produced by Low-Temperature Combustion Using Modified Silica Fabric

Hydrogenation of CO2 on Co–Ni Catalysts Produced by Low-Temperature Combustion Using Modified Silica Fabric

Increasing cerium dispersion favours lattice oxygen activity of cobalt oxides for CO catalytic combustion

Removing carbon monoxide with catalytic combustion technology is an effective and economical solution. Highly efficient conversion of CO at low temperatures can be achieved by introducing a catalyst, and its application in automotive exhaust emissions and preferential oxidation of CO in fuel cells is remarkable. In this work, catalysts were prepared by mixing the prepared cerium organic framework with Co3O4, and after calcination at 400 °C, the organic framework collapsed, resulting in a uniform dispersion of Ce on the Co3O4 nano surface. Experimental results demonstrated that the required temperature of the catalyst is 101 °C when the conversion is 90 %, and it remained stable over the 75 h tested at 100 °C. High resolution transmission electron microscopy (HRTEM) revealed that Ce/Co3O4 primarily exposed 311 surface. Combined with DFT calculations, the catalysts may improve the catalytic combustion activity of CO by multiplying the oxygen vacancies and modulating the dispersion of Ce atoms. The reaction occurred on the 311 surface predominantly. Activated CO* preferred to react with the lattice oxygen at the Ce-O-Co linkage compared to the lattice oxygen at Co-O-Co. Energy barrier for the rate dictating step in the complete catalytic cycle is 0.42 eV. This work not only provides experimental support and theoretical basis for the design of low-temperature catalytic combustion CO catalysts, but also provides new ideas for the doping of metal oxides with lanthanide metals.