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Atmospheric oxidation experiments of iso-propylamine (IPA) were conducted in a jet-stirred reactor over the temperature range from 550 to 870 K at fuel-equivalence ratios of 0.5 and 2.0. A combination of synchrotron vacuum ultraviolet (SVUV) photoionization and time-of-flight mass spectrometry (TOFMS) was utilized to identify and quantify oxidation products and intermediates. Compared to the previous n-propylamine (NPA) low-temperature oxidation [Proc. Combust. Inst., 39 (2023) 295–303.], some intermediates and products were newly observed among the 34 detected species, including nitrosyl hydride, methylamine, acetonitrile, nitrous oxide, ethyl isocyanide, propanenitrile, 2-propanimine, n-methylformamide and 2-methylallylamine. A kinetic model consisting of 815 species and 4402 reactions was developed based on the iso-propanol model [Prog. Energy Combust. Sci. 67 (2018) 31–68.] and an ethylamine model [Prog. Energy Combust. Sci. 44 (2014) 40–102.]. The onset temperature of IPA and O 2 consumption is 750 K under both lean and rich conditions. Rate-of-production (ROP) and sensitivity analyses were performed at 800 K to illustrate the reacting paths from parent fuel to major intermediates and products, and identify the most sensitive reactions. H 2 O 2 (+M) = 2OH(+M) is the most sensitive reaction with a promoting effect on IPA consumption while 2HO 2 = H 2 O 2 +O 2 is the most inhibiting one. Important N-containing pollutants like NH 3 , NOx, HCN, CH 3 NH 2 and so on were analyzed with respect to their reaction routes. (CH 3) 2 CNH is abundant due to the H-abstraction reactions between tC 3 H 6 NH 2 radical with O 2. This work was made for gaining a more comprehensive insight into the oxidation of IPA and make a foundation for further exploring amine chemistry. [ABSTRACT FROM AUTHOR]

Pyrolysis of 1,2,4-trimethylcyclohexane (T124MCH) at 30 and 760 Torr has been investigated by using VUV-synchrotron photoionization molecular-beam mass spectrometry. In general, the ambient pressure leads to peak-shaped profiles of light hydrocarbons, while the monotonically increasing curves are observed for light hydrocarbons and aromatics in pyrolysis of T124MCH at low pressure. A detailed mechanism involving 530 species and 3160 reactions developed by the authors previously was used for the simulation of T124MCH with reasonable predictions. The consumption of T124MCH followed similar patterns at both pressures, namely the H-abstractions on the first, secondary, and tertiary carbon atoms are the main consumption reactions of T124MCH. The isomerization reactions transform the C 9 H 17 radicals to branch-chain hydrocarbons, which are the precursors of light hydrocarbons such as ethane and propene. Sensitivity analysis indicates that the CH 3 consumption reactions are the most significant promoting reactions at both pressures. Isomerization reactions of T124MCH tend to play significant inhibiting effect on T124MCH pyrolysis. Compared to T124MCH oxidation, T124MCH pyrolysis tends to produce large quantities of benzene and toluene. These results will improve the understanding of the combustion and soot formation of T124MCH as a potential aviation surrogate fuel. [ABSTRACT FROM AUTHOR]

With the increasing dominance of electricity retailers in the electricity market, it has become a new trend for the data center (DC) to participate in sales-side transactions. However, data center electricity retailers (DCERs) and DCs that purchase electricity by DCERs, as different stakeholders, will inevitably face conflicts of interest. To promote the benefit distribution of DCs and DCERs to achieve a win–win situation, our study proposes an optimal scheduling method based on multiple games and establishes a mixed game model by integrating the master–slave game method and the cooperative game method, in which DCERs take profit maximization as the optimization goal, while Internet DCs take the lowest total cost as the optimization goal. The master–slave game is adopted between the DCER and the DC, and the cooperative game is adopted among the members of the DC. The benefits are distributed through Nash bargaining. The model is solved by using the particle swarm optimization algorithm combined with the alternating direction method of multipliers. To demonstrate the effectiveness of our proposed method, we provide an illustrative example that showcases its ability to not only increase DCER revenue by 136.04% but also decrease total DC costs by 9.39%. As a result, our method facilitates a more equitable distribution of cooperation revenues. [ABSTRACT FROM AUTHOR]

The pyrolysis of isopropylamine (IPA) was studied in a jet-stirred reactor at 1 atm within 670–1100 K. Pyrolysis products and intermediates were identified and quantified with both synchrotron vacuum ultraviolet photoionization mass spectrometry and gas chromatography analysis. Propiolonitrile, propanenitrile, 1-methylethenylamine, 3-butenenitrile, pyridine and benzonitrile were newly identified compared with previous studies of amines. HCN and 1-methylethenylamine were found to be the dominant N-containing species in IPA pyrolysis. The peak mole fractions and temperatures of C 1 -C 2 hydrocarbons are generally higher than C 3 -C 4 ones. The peak temperatures tend to rise with the increase of degree of unsaturation for hydrocarbons with the same C numbers. Based on the observations, a detailed kinetic model consisting of 429 species and 2407 reactions was developed with reasonable predictions against the measured data. Rate-of-production analysis indicates that IPA is mainly consumed by the H-abstraction at the Cα atom: (CH 3) 2 CHNH 2 + H = (CH 3) 2 CNH 2 +H 2. Sensitivity analysis shows that the unimolecular decomposition via C C bond cleavage and H-abstraction at the Cα atom play promoting roles. The H-abstraction of propene by H-atom yielding allyl radical and self-combination of methyl radicals forming ethane exhibit inhibiting effects. Compared to the pyrolysis of n-propylamine (NPA), more amine- or imine-like species were generated during NPA pyrolysis while more nitriles were detected in IPA pyrolysis. Moreover, the peak temperatures of hydrocarbons in both NPA and IPA pyrolysis shift to higher values with the increase of degree of unsaturation. The results will enrich the understanding of IPA for further combustion kinetic studies of low sooting fuels. [ABSTRACT FROM AUTHOR]

Pyrolysis of norbornadiene (NBD) was investigated in a jet-stirred reactor at 760 torr and within the temperature range of 560 to 1100 K. 37 products and intermediates ranging from m/z = 26 to 178 were identified and quantified by using synchrotron radiation photoionization molecular-beam mass spectrometry accompanied by gas chromatography. The C 7 H 8 isomers, including NBD, cycloheptatriene (CHT) and toluene (A1CH 3), were differentiated. Acetylene (C 2 H 2), cyclopentadiene (C 5 H 6), C 7 H 8 isomers and other aromatics are abundant during the pyrolysis process. A detailed kinetic model was developed with reasonable predictions against the measured results, involving 264 species and 1259 reactions, which is helpful to understand the kinetic and heat features of initial consumption as well as the synergistic effect of C 2 H 2 , C 5 H 6 and A1CH 3 to the formation of aromatics. Rate-of-production analysis shows that the pyrolysis of NBD experiences two stages. The first stage involves the isomerization and decomposition of NBD, yielding A1CH 3 , CHT, C 5 H 6 and C 2 H 2. Branching ratio analysis shows that C 5 H 6 and C 2 H 2 are dominant products in the first stage. Heat release analysis indicates that the first stage is endothermic. The second stage involves the pyrolysis and interactions of first-stage products to produce light hydrocarbons and polycyclic aromatic hydrocarbons like indene, naphthalene, acenaphthylene, fluorene and phenanthrene. Three routes dominate the formation of indene, including C 5 H 6 + C 5 H 5 , benzyl radical + C 2 H 2 and cycloheptatrienyl radical + C 2 H 2 , the last one of which has been scarcely considered in the previous investigation. Sensitivity analysis indicates the reactions in the first stage exhibit strong promoting effects for the consumption of NBD, while the second-stage reactions play minor roles in NBD consumption. This work would enrich the understanding of NBD consumption, PAH formation and heat release. [ABSTRACT FROM AUTHOR]

As a polar solvent, N, N-Dimethylformamide (DMF) is a potential source of volatile organic compounds during industrial processing. The potential energy surface and pressure-dependent rate coefficients of DMF primary and secondary thermal decomposition were theoretically investigated by automatic ab initio calculations. A singlet aminohydroxycarbene route generating CO is found to be the most energetically favored channel among the unimolecular initiation reactions with a tight transition state. A kinetic model was proposed for DMF pyrolysis prediction and validated against the speciation data newly obtained from synchrotron vacuum ultraviolet photoionization mass spectrometry in a flow reactor within 773 K–1048 K and literature data in a jet stirred reactor within 450 K–900 K at atmospheric pressure. Satisfactory agreements were obtained for the major intermediates and products, but the model failed to capture the formation of some oxygenated compounds, possibly due to the missing reaction pathway for bimolecular addition. During pyrolysis, DMF is mainly consumed by the hydrogen abstraction reaction as the relatively high C N bond energy hinders the barrierless homolytic cleavage. Unlike aldehydes where the carbonyl site is favored, H-abstraction from DMF methyl sites is prevalent, although the acylamino group readily undergoes decarbonylation and β-scission forming oxygenated and nitrogenous parts. Consequently, CO and HCN are the major pyrolysis products. Besides, by incorporating essential high temperature kinetics, extended validation was conducted against the available intermediate temperature autoignition delay times (1000–1350 K, 2 bar) and laminar burning velocity data, and the reason for the discrepancy between the model prediction and experiments was inferred according to the sensitivity analyses. [ABSTRACT FROM AUTHOR]

• Oxidation experiments on C 3 H 6 were conducted by using a jet-stirred reactor at 12.0 atm within 725–1015 K, and equivalence ratios of 0.5 and 3.0. • Using online gas chromatography and gas chromatography-mass spectrometry, sixteen products and intermediates including light hydrocarbons, oxygenated and aromatic species were identified and quantified. • Under the current experimental conditions (P = 12.0 atm), no NTC behavior was observed in the C 3 H 6 conversion curve. • Rate-of-production analysis for C 3 H 6 indicates the four main pathways for high-pressure oxidation of C 3 H 6 , namely hydrogen atom abstraction reactions, OH addition reactions, H atom addition reactions, and the formation of C 3 H 6 O1-2. • Sensitivity analysis for C 3 H 6 reveals that the reactions H 2 O 2 (+M) <=> 2OH(+M) and the H-abstraction of C 3 H 6 by OH radicals are the most promoting and inhibiting reactions for C 3 H 6 consumption, respectively. • Comparing the current C 3 H 6 oxidation at 12.0 atm with the results from Cong et al. and Burke et al. at about 1.0 atm in the literature, the increase in pressure is conducive to complete fuel consumption, making C 3 H 6 consume faster and tend to be fully consumed at lower temperatures. Comprehensive experimental and kinetic studies of propene (C 3 H 6) oxidation were conducted by using a jet-stirred reactor at 12.0 atm within 725–1020 K under both fuel-lean (Φ = 0.5) and fuel-rich (Φ = 3.0) conditions. Molecular species concentration profiles were obtained by using online gas chromatography and gas chromatography-mass spectrometry, including CO, CO 2 , CH 4 , C 2 H 4 , C 2 H 6 , A-C 3 H 4 , C 3 H 8 , 1,3-C 4 H 6 , 1-C 4 H 8 , nC 4 H 10 , CH 3 CHO, C 2 H 3 CHO, CH 3 COCH 3 , C 3 H 6 O1-2 CH 3 CH 2 CHO, and C 6 H 6. Sixteen products and intermediates including light hydrocarbons, oxygenated and aromatic species were identified and quantified. Based on Aramco Mech 3.0 and previous works, the rate coefficients of some key elementary reactions were updated, and a detailed kinetic reaction model was developed with reasonable predictions involving 587 and 3037 reactions. Rate-of-production analysis indicates the four main pathways for high-pressure oxidation of C 3 H 6 , namely hydrogen atom abstraction reactions, OH addition reactions, H atom addition reactions, and the formation of C 3 H 6 O1-2. Sensitivity analysis reveals that H 2 O 2 (+M) <=> 2OH(+M) and the H-abstraction of C 3 H 6 by OH radicals are the most promoting and inhibiting reactions for C 3 H 6 consumption, respectively. The benzene formation during C 3 H 6 oxidation was analyzed, mainly generated by the C 1 + C 5 channel and consumed by OH addition. It was found that increasing pressure can decrease the initial reaction temperature and increase the conversion of C 3 H 6. The importance of addition and hydrogen abstraction reactions in the oxidation of C 3 H 6 was identified by analyzing the pressure effect. To confirm its validity, the proposed kinetic model could be used to the previous literature data, including JSR oxidation at around 1 atm and ignition delay times for C 3 H 6. These experimental and modeling efforts provide a basis for gaining a more comprehensive insight into the oxidation of propene. [ABSTRACT FROM AUTHOR]

• The flame characteristics of the mixed C 2 H 2 /O 2 /N 2 premixed jet flames were investigated from φ = 0.5 to 6.0. • The average particle size and particle distribution as a function of height above burner were correlated with flame temperatures. • Larger PAH monomers have a stronger aggregation ability and are more likely to form initial soot particles. • The primary soot particle growth stagnates as PAHs do not continue to aggregate. This work aims to identify the relationship between the temperature and soot formation in the C 2 H 2 laminar flames. The effects of flow rates and equivalence ratios on the flame temperatures and structures were investigated. The flame length increases with the increase of the equivalence ratio. Meanwhile, the flame color changes from pale blue to bright green from the fuel-lean to stoichiometric condition, and further to bright yellow under the ultra-rich conditions. By sampling and observing the morphology of soot at different heights of the flame, we reveal the factors affecting the size of soot. As the flame height increases, the growth rate of soot agglomerates becomes faster. The contribution of surface growth to the soot particle size decreases gradually. The collision and aggregation predominate the soot growth. To uncover the soot formation mechanism, the average particle size and particle distribution as a function of height above burner were correlated with flame temperatures. Furthermore, the underlying mechanisms behind the nucleation and growth of nascent soot particles from polycyclic aromatic hydrocarbons (PAHs) were reveal via ReaxFF molecular dynamics simulations. The results show that the aggregation ability of PAHs decreases as the temperature increases. The aggregation ability of PAHs is also affected by size, and the larger the size, the stronger the aggregation ability of PAHs. Both the experimental and simulation results provide novel insights into the development of combustion kinetic model for soot formation in sooting fuels. [ABSTRACT FROM AUTHOR]

To study the formation pathways of aromatic compounds in the oxidation process of soot precursors under different equivalent ratios (φ), two parts of work were carried out. The present work was the part I: the oxidation of 1,3-butadiene (1,3-C 4 H 6) was studied in a jet-stirred reactor at high-pressure (12 atm) within a temperature range covering 575–1075 K, at fuel equivalence ratios (φ) of 0.5 and 3.0. Part II focused on the study of oxidation of a two-compound mixture of acetylene and 1,3-butadiene. Mole fraction profiles of 20 species obtained by GC/MS analysis were identified and quantified. The measured species profiles serve as a data base for the further development of a detailed chemical kinetic reaction mechanism AramcoMech 3.0 generated by Zhou et al. previously for describing the ignition delay time and laminar flame speed of 1,3-butadien. The resulting reaction mechanism comprising 625 species and 3188 reactions was found to be able to describe credibly the experimental species profiles. Rate-of-production (ROP) analysis reveals that addition reactions of H and OH radicals to 1,3-C 4 H 6 are the major channels governing 1,3-C 4 H 6 consumption under both fuel-lean and fuel-rich conditions. Acetylene (C 2 H 2), vinyl acetylene (C 4 H 4), and propargyl radicals (C 3 H 3) are playing important roles within the formation of mono-aromatics. Here, benzene is mainly formed via the C 2 + C 4 pathways instead of the C 1 + C 5 routes. Furthermore, C 3 H 3 radicals were found to play a key role within C 6 H 5 CH 3 formation. Naphthalene are formed by the reactions of C 6 H 6 and 1,3-C 4 H 6 or C 4 H 5 N/I radicals. These results will enrich the understanding of elevated pressure chemistry of 1,3-C 4 H 6 and facilitate to further model development and validation focusing on a more detailed description of the formation network of aromatic compounds. [ABSTRACT FROM AUTHOR]

The high-pressure oxidation experiments of a two-fuel component mixture of 0.2%1,3-butadiene (1,3-C 4 H 6), 0.2% acetylene (C 2 H 2), nitrogen (N 2) and oxygen (O 2) (see Table 3, No.1 & 2) were carried out in a jet-stirred reactor (JSR) at 12 atm within 575–1025 K under fuel-lean (φ = 0.5) and fuel-rich (φ = 3.0) conditions. 15 species profiles of products and intermediates were identified and quantified by gas chromatography (GC) and gas chromatography-mass spectrometer (GC–MS). This work is enlarging the experimental data base obtained from the study of C 2 H 2 /1,3-C 4 H 6 mixtures reported earlier. The updated comprehensive chemical reaction kinetic model based on the experimental data of the current work and the AramcoMech 3.0 model is containing 635 species and 3291 reactions. The comparison between the new experimental data base and the data predicted by the updated model was done for major products and intermediates, such as oxygenated species and aromatics. In general, a good agreement was found. It was shown that the fuel-rich oxidation of C 2 H 2 /1,3-C 4 H 6 mixtures (see Table 3, No.2) contributes largely to benzene (C 6 H 6) formation compared to neat oxidation of C 2 H 2 (see Table 3, No.4) as well as of 1,3-C 4 H 6 (see Table 3, No.6). At temperatures below 900 K, C 6 H 6 is mainly formed through the C2 + C5 channel: C 2 H 2 + C 5 H 5 → C 6 H 5 CH 2 → C 6 H 6. The C2 + C4 pathway: C 4 H 5 -I/N + C 2 H 2 → FULVENE → C 6 H 6 tends to be the dominant route for C 6 H 6 formation at temperatures above 900 K. A rate-of-production (ROP) analysis indicates that both C 2 H 2 and 1,3-C 4 H 6 are consumed mainly by addition reactions with mainly OH radicals involved. The consumption of C 2 H 2 decreases with increasing values of the fuel-equivalence (φ), while the consumption of 1,3-C 4 H 6 is much less effected by the specific φ values. Compared with the results obtained at fuel-lean condition (φ =0.5), the C 3 H 5 -A and C 5 H 5 radicals consume more C 2 H 2 with increasing temperatures at fuel-rich condition (φ =3.0). The oxidation process of 1,3-C 4 H 6 is occurring mainly by H-abstraction with OH radicals, H-addition, and subsequent reactions. According to sensitivity analysis, the reaction H 2 O 2 (+ M) ⇌ OH + OH (+ M) can promote the consumption of C 2 H 2 and of 1,3-C 4 H 6 ; however, the promoting effect gradually decreases with increasing of φ values. On the other hand, the consumption of C 2 H 2 can also be promoted by the reactions C 3 H 5 -A + C 2 H 2 ⇌ CVCCVCCJ and 1,3-C 4 H 6 + OH ⇌ C 3 H 5 -A + CH 2 O, in addition, the promotion effect can gradually enhance with increasing φ values. For 1,3-C 4 H 6 consumption, the promoting effect of the reaction 1,3-C 4 H 6 + CH 3 ⇌ C 4 H 5 -I + CH 4 also strengthens. The results of the present work contribute to a better understanding of benzene formation at high-pressures in particular and provide valuable information for the study of the formation pathways of PAHs and soot as well. [ABSTRACT FROM AUTHOR]

The oxidation of ethylene (C 2 H 4) was performed in a jet-stirred reactor (JSR) at the equivalence ratios (Φ) of 0.5, 1.0, and 3.0, within the temperature range of 650–1000 K, at 12.0 atm. Six C 1 -C 3 hydrocarbons and four oxygenated species were identified and quantified by using online GC and GC-MS. Among them, acrolein, propanal, and epoxypropane were newly detected compared to previous oxidation studies of C 2 H 4. A detailed kinetic model involving 125 species and 671 reactions was developed, and its predictions were found to be in reasonable agreement with the measured data. Generally, the peak concentrations of hydrocarbons and oxygenated species tend to increase with the increase of Φ, while the inorganic substances exhibit contrary tendencies. Rate-of-production analysis indicates that C 2 H 4 consumption is generally governed by the addition of H-atom and OH radicals, which mostly transform to C 2 H 5 under rich conditions and to CH 2 CH 2 OH under lean condition. Sensitivity analysis reveals that the reactions H 2 O 2 (+M) <=> 2OH(+M) and CH 2 O + O 2 <=> HCO + HO 2 are the most promoting and inhibiting reactions for C 2 H 4 consumption, respectively. By comparing the results of 1.0-59.2 atm, it can be found that the increase of pressure leads to the reduction of the initial reaction temperature. Under higher pressure, the reaction temperature interval of C 2 H 4 shifts towards a lower temperature. The current mechanism could reproduce the literature-reported ignition delay times and laminar flame velocities under wide pressures. The results will enrich the understanding of the high-pressure oxidation of C 2 H 4 and serve as a foundation for developing large hydrocarbon fuel models. [ABSTRACT FROM AUTHOR]

The oxidation of CH 4 was investigated in a jet-stirred reactor under equivalence ratios (Φ) of 0.5 and 1.0 within 875–1050 K at 12 atm. Mole fraction profiles of six species (CO, CO 2 , CH 4 , C 2 H 4 , C 2 H 6 and propene (C 3 H 6)) were quantified. Compared with previous oxidation studies of CH 4 , C 3 H 6 was newly detected. A detailed chemical kinetic model consisting of 92 species and 616 reactions was developed to predict the oxidation of CH 4 under a wide range of pressures. In general, the onset temperature of CH 4 oxidation shifts higher with Φ increasing. Compared with previous models, the experimental data were reasonably reproduced by the present model. Rate-of-production (ROP) and sensitivity analyses reveal that the consumption of CH 4 proceeds predominantly via H-abstraction by OH radicals under both conditions. The reaction sequences CH 4 →CH 3 →CH 3 O/CH 2 O→HCO→CO and CH 3 →C 2 H 6 →C 2 H 5 are the two major channels governing CH 4 conversion. C 3 H 6 is mainly formed by the reaction C 3 H 6 +H=CH 3 +C 2 H 4 under lean condition above 975 K. Particular attention was paid to the oxidation and negative temperature coefficient (NTC) behavior of CH 4 at 1–90 atm and a wide range of Φ. It can be found that the increase of pressure is conducive to fuel consumption and the NTC behaviors are observed within temperatures of 810–900 K at pressures higher than 30 atm and Φ = 0.3–2.0. ROP analyses reveal that the competition between methyl peroxide and its subsequent chain-branching is responsible for the NTC behavior in CH 4 oxidation. Moreover, the model also gives reasonable predictions against oxidation data (1–90 atm), ignition delay times (800–2000 K) and laminar burning velocities (1-10 atm) reported in the literature. This work will enrich the understanding of CH 4 oxidation and promote experimental and theoretical studies on the oxidation of other larger hydrocarbons. [ABSTRACT FROM AUTHOR]

Pyrrole is a typical fuel nitrogen model compound of coal and it is the precursor of fuel-NO x. The mechanism and kinetics of pyrrole pyrolysis were studied in a jet-stirred reactor coupled with a synchrotron vacuum ultraviolet molecular beam mass spectrometer and a gas chromometer over the temperature range of 940–1240 K at atmospheric pressure. Two sets of new data of pyrrole pyrolysis were provided. Based on the photoionization efficiency analysis, nitrogenous products are mainly produced in the form of nitriles and dinitriles. Of the pyrrole pyrolysis products, six nitriles were newly identified including methyl isocyanide (C 2 H 3 N), cyanogen (NCCN), isocyanogen (CNCN), propionitrile (C 3 H 5 N), propanedinitrile (C 3 H 2 N 2), butanedinitrile (C 4 H 4 N 2). Mole fractions of pyridine (C 5 H 5 N), C 3 H 2 N 2 , cyanovinylacetylene (C 5 H 3 N), and benzonitrile (C 7 H 5 N) were also quantified. HCN is the dominant nitrogenous product of pyrrole pyrolysis. C 2 H 2 and CH 4 are the major carbonaceous products. An updated pyrrole kinetic model was proposed comprising 196 species and 2939 reactions. The production of pyridine and several nitriles during pyrrole pyrolysis could be reasonably predicted using the current model. C 3 H 2 N 2 is mainly produced by the reaction between CH 2 CN and other nitriles, and it is converted into CH 2 CN and CH 3 CN. The reaction between CH 3 and C 3 H 2 N 2 is the most sensitive reaction for promoting the consumption of C 3 H 2 N 2. Results of this work confirm the importance of dinitriles and nitriles during the pyrolysis of pyrrole as an important fuel-NO x model compound of coal and other nitrogen-containing fuels. [ABSTRACT FROM AUTHOR]

Pyridine is an important model compound of fuel-nitrogen during the coal combustion process. The lean oxidation of pyridine was studied over 800–1100 K at atmospheric pressure with the equivalence ratio of 0.4 in a jet-stirred reactor. Pyridine and its oxidation products were measured by tunable synchrotron vacuum ultraviolet photoionization molecular-beam mass spectrometry and gas chromatography analyzer. Three-stage consumption phenomenon of pyridine and O 2 was observed including a fast consumption stage at 910–920 K, a moderate consumption stage at 920–1000 K, and a slow consumption stage at 1000–1100 K. HCN, N 2, N 2 O, and HNCO are the major nitrogenous oxidation products of pyridine. CO, CO 2 , HCN, and HNCO are the dominant carbonaceous products. HNCO is uniquely detected in the lean oxidation of pyridine compared with rich oxidation. A new pyridine LTO 2.0 model comprising 210 species and 1349 reactions was proposed, providing a good prediction of pyridine and its major oxidation products against experimental data. N 2 O emission is larger than NO at 1100 K. HCN is the dominant nitrogenous intermediate under both fuel-lean and fuel-rich conditions. Results of this work provide a detailed analysis of the nitrogen evolution mechanism of pyridine oxidation under the fuel-lean condition, which is close to the real industrial low-temperature coal combustion processes including the MILD combustion, fluidized bed combustion, etc. [ABSTRACT FROM AUTHOR]

N, N-dimethylformamide (DMF) is a kind of general solvent in Li-ion industry and nitrogen-containing component of amines fuels. The trace vapor of DMF is very harmful to human and environment, which could be treated by pyrolysis. The pyrolysis of DMF was newly carried out in a flow reactor at 30 Torr within 873–1273 K. Synchrotron radiation single photoionization coupled with molecular beam mass spectrometry was employed to detect the reactants, intermediates and products. 26 species were identified and quantified. Products related to NOx, such as nitrosomethane, nitrosyl cyanide and N-methylformamide were identified. With the temperature increasing, the mole fractions of species tend to increase monotonically, while nitrosyl cyanide, ethyl radical, cyclopropane, carbon monoxide, ethanol, acetaldehyde and ethanol exhibit peak-shaped curves. Hydrogen abstractions and dissociations are the main initial pathways of DMF consumption. As the main hydrocarbon products, methane and ethylene are predominantly formed by the H abstraction reaction by methyl radical and the β-scission of ethyl radical, respectively. Carbon monoxide is mainly generated from the dissociation of DMF and its mole fraction is at the same level as the fuel DMF. HCN is the most abundant product among all the carbonitride species via H abstraction of CH 2 =NH as well as the collisions of CN with alkanes and aldehydes. These results provide a theoretical basis for further study of treating DMF in the exhaust fumes through pyrolysis and have reference value for the clean utilization of amine fuels. [Display omitted] • The pyrolysis of DMF was newly carried out in a flow reactor at 30 Torr within 873–1273 K. • 26 species were dected via synchrotron radiation single photoionization and molecular beam mass spectrometry. • Hydrogen abstractions and dissociations are the main consumption pathways of DMF. • Products related to NOx, such as nitrosomethane, nitrosyl cyanide andN-methylformamide were detected. • With the temperature increasing, most intermediates tend to increase monotonically. [ABSTRACT FROM AUTHOR]