Thermochimica Acta最新文献

英文中文

Experimental study on the influence of CO2 injection on coal spontaneous combustion characteristics and molecular functional groups

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-01-01 DOI: 10.1016/j.tca.2024.179914

Jiayong Zhang , Zuxin Lv , Xiao Cui , Liwen Guo , Yanlei Guo , Jianguo Wu , Jingbin Fu

The study aims to investigate changes in the spontaneous combustion characteristics of coal and its microscopic reaction mechanisms in a CO₂ atmosphere. Programmed heating experiments and thermogravimetric analysis were conducted to examine index gas and combustion parameters in both air and CO₂ atmospheres. Molecular functional group changes were analyzed via in situ infrared experiments, and their correlation with index gases was assessed using the grey correlation method. The results revealed that CO₂ injection during the initial heating stage increased the production of CO, CH₄, and C₂H₄. However, beyond 160 °C, CO₂ effectively reduced the oxidation activity of functional groups and significantly inhibited the production of indicator gas. The characteristic temperature range of coal samples exhibited a 'lag' phenomenon under the influence of CO₂, resulting in a prolonged combustion stage with reduced mass loss and heat discharge. Following CO₂ injection, the -OH concentration significantly decreased, while C=O gradually increased. Additionally, the concentrations of -COOH, aliphatic hydrocarbons, and aromatic hydrocarbons initially increased with rising temperature and then declined. The contribution of these groups to gas generation followed the sequence of oxygen-containing functional groups > aliphatic hydrocarbons > -OH > aromatic hydrocarbons.

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引用次数: 0

Flame-retardant effects of NH2-MIL-53(Al) in combination with phosphorus-containing and nitrogen-containing flame retardants on polypropylene

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-01-01 DOI: 10.1016/j.tca.2024.179913

Liang Yu , Lv Shen , Hongzhe Zhong , Ru Zhou , Min Hao , Juncheng Jiang

Polypropylene (PP) flammability poses great fire risks for its application. A metal-organic framework (MOF), NH₂-MIL-53(Al), was synthesized and subsequently integrated into PP, the flame-retardant efficacy in conjunction with piperazine pyrophosphate (PAPP) and melamine cyanurate (MCA) was additionally examined. When the total mass fraction of the additives was 25 %, the limiting oxygen index (LOI) of PP composite reached 31.1 %, it also passed the UL-94 test with a V-0 rating. The peak heat release rate (pHRR) and the total heat release rate (THR) was reduced by 88.55 % and 79.75 %, respectively, compared with the pure PP. The char residual char percentage increased to 8.02 %. The Tensile Strength reached 30.1 MPa. The results indicate that adding NH₂-MIL-53(Al) significantly enhanced the flame retardancy and thermal stability of PP composites, without significantly affecting their mechanical properties, which offers a novel potential direction for the advancement of polymer flame retardants (FRs).

{"title":"Flame-retardant effects of NH2-MIL-53(Al) in combination with phosphorus-containing and nitrogen-containing flame retardants on polypropylene","authors":"Liang Yu , Lv Shen , Hongzhe Zhong , Ru Zhou , Min Hao , Juncheng Jiang","doi":"10.1016/j.tca.2024.179913","DOIUrl":"10.1016/j.tca.2024.179913","url":null,"abstract":"<div><div>Polypropylene (PP) flammability poses great fire risks for its application. A metal-organic framework (MOF), NH<sub>2</sub>-MIL-53(Al), was synthesized and subsequently integrated into PP, the flame-retardant efficacy in conjunction with piperazine pyrophosphate (PAPP) and melamine cyanurate (MCA) was additionally examined. When the total mass fraction of the additives was 25 %, the limiting oxygen index (LOI) of PP composite reached 31.1 %, it also passed the UL-94 test with a V-0 rating. The peak heat release rate (pHRR) and the total heat release rate (THR) was reduced by 88.55 % and 79.75 %, respectively, compared with the pure PP. The char residual char percentage increased to 8.02 %. The Tensile Strength reached 30.1 MPa. The results indicate that adding NH<sub>2</sub>-MIL-53(Al) significantly enhanced the flame retardancy and thermal stability of PP composites, without significantly affecting their mechanical properties, which offers a novel potential direction for the advancement of polymer flame retardants (FRs).</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"743 ","pages":"Article 179913"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-temperature heat capacity, phase transitions and thermodynamic functions of 2-furfurylamine

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-01-01 DOI: 10.1016/j.tca.2024.179915

Anna I. Druzhinina , Olga V. Dorofeeva , Sergey V. Tarazanov , Vera A. Lukyanova , Dmitriy Yu. Ilin

Heat capacities of 2-furfurylamine were measured by low-temperature adiabatic calorimetry in the temperature range from 5.6 to 356.1 K. Two phase transitions, solid phase transition and melting, were revealed at temperatures of 180.4 K and 228.17 K. Thermodynamic characteristics determined from experimental data show that the mechanism of solid phase transition is intermediate between order-disorder and displacive type. This conclusion is in agreement with X-ray crystallography data (Seidel et al., 2019). The standard thermodynamic functions in the condensed state (molar heat capacity, enthalpy, entropy and Gibbs energy) were calculated in the temperature range 5 - 350 K. Using the determined value of entropy for liquid 2-furfurylamine and available value of

Δ_{f} H_{m}^{\circ} (l)

, the properties of formation,

Δ_{f} S_{m}^{\circ} (l)

and

Δ_{f} G_{m}^{\circ} (l)

, were obtained. The thermodynamic functions of gaseous 2-furfurylamine were calculated taking into account the internal rotation in this molecule. The required molecular constants were determined from quantum chemical calculations.

{"title":"Low-temperature heat capacity, phase transitions and thermodynamic functions of 2-furfurylamine","authors":"Anna I. Druzhinina , Olga V. Dorofeeva , Sergey V. Tarazanov , Vera A. Lukyanova , Dmitriy Yu. Ilin","doi":"10.1016/j.tca.2024.179915","DOIUrl":"10.1016/j.tca.2024.179915","url":null,"abstract":"<div><div>Heat capacities of 2-furfurylamine were measured by low-temperature adiabatic calorimetry in the temperature range from 5.6 to 356.1 K. Two phase transitions, solid phase transition and melting, were revealed at temperatures of 180.4 K and 228.17 K. Thermodynamic characteristics determined from experimental data show that the mechanism of solid phase transition is intermediate between order-disorder and displacive type. This conclusion is in agreement with X-ray crystallography data (Seidel <em>et al</em>., 2019). The standard thermodynamic functions in the condensed state (molar heat capacity, enthalpy, entropy and Gibbs energy) were calculated in the temperature range 5 - 350 K. Using the determined value of entropy for liquid 2-furfurylamine and available value of <span><math><mrow><msub><mstyle><mi>Δ</mi></mstyle><mi>f</mi></msub><msubsup><mi>H</mi><mrow><mi>m</mi></mrow><mo>∘</mo></msubsup><mrow><mo>(</mo><mi>l</mi><mo>)</mo></mrow></mrow></math></span>, the properties of formation, <span><math><mrow><msub><mstyle><mi>Δ</mi></mstyle><mi>f</mi></msub><msubsup><mi>S</mi><mrow><mi>m</mi></mrow><mo>∘</mo></msubsup><mrow><mo>(</mo><mi>l</mi><mo>)</mo></mrow></mrow></math></span> and <span><math><mrow><msub><mstyle><mi>Δ</mi></mstyle><mi>f</mi></msub><msubsup><mi>G</mi><mrow><mi>m</mi></mrow><mo>∘</mo></msubsup><mrow><mo>(</mo><mi>l</mi><mo>)</mo></mrow></mrow></math></span>, were obtained. The thermodynamic functions of gaseous 2-furfurylamine were calculated taking into account the internal rotation in this molecule. The required molecular constants were determined from quantum chemical calculations.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"743 ","pages":"Article 179915"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accurate determination of purity for organic compounds using adiabatic calorimetry

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2025-01-01 DOI: 10.1016/j.tca.2024.179916

Huimin Yan , Fan Yang , Nan Yin , Yan Kou , Quan Shi

Adiabatic calorimetry is a reliable method for determining the purity of organic compounds, offering significant advantages over chromatography by eliminating the need for impurity separation. Despite its longstanding application, research in this area has been limited. This study comprehensively assessed the purity of tetradecanoic acid, n-heptadecane, and phenol using adiabatic calorimetry, comparing the results with those obtained through chromatography. The results demonstrated that tetradecanoic acid purity can be accurately measured, while n-heptadecane exhibited satisfactory repeatability in purity determination without sample separation in polycrystalline forms. Furthermore, the purity of phenol was effectively assessed using adiabatic calorimetry, where chromatography faced challenges. Overall, this study validates adiabatic calorimetry as a robust technique for organic compound purity determination and suggests avenues for further research in this domain.

引用次数: 0

Study on the factors influencing the thermal runaway hazards of styrene-acrylonitrile bulk copolymerization 苯乙烯-丙烯腈大量共聚热失控危害影响因素研究

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-21 DOI: 10.1016/j.tca.2024.179912

Yang Liu , Weixin Li , Shudong Lin , Hui Liu , Zicheng Xie , Wanyan Li , Jiwen Hu , Xuefeng Gui

The styrene-acrylonitrile bulk copolymerization reaction has a high risk of thermal runaway, but the factors influencing the thermal hazards of the reaction have not been adequately investigated. In this paper, the effects of different factors on the thermal runaway behavior of the styrene-acrylonitrile copolymerization are investigated using a combination of simulation and calorimetric testing. The simulation results indicate that increasing the proportion of styrene in the monomer feed significantly delays the onset of thermal runaway. The calorimetric results show that for di-tert-butyl peroxide (DTBP), azodiisobutyronitrile (AIBN) and tert-butyl peroxy benzoate (TBPB) initiators as examples, the TBPB-initiated copolymerization is found to have the maximum temperature-rising rate and pressure-rising rate. Under adiabatic runaway, the temperature and pressure change significantly with increasing TBPB concentration, indicating a great potential risk of thermal runaway. Calculation of kinetic parameters based on calorimetric data reveals thermal runaway mechanism.

苯乙烯-丙烯腈大体积共聚反应具有很高的热失控风险，但影响该反应热危害的因素尚未得到充分研究。本文采用模拟和量热测试相结合的方法，研究了不同因素对苯乙烯-丙烯腈共聚反应热失控行为的影响。模拟结果表明，增加单体进料中苯乙烯的比例可显著延缓热失控的发生。热量测定结果表明，以二叔丁基过氧化物（DTBP）、偶氮二异丁腈（AIBN）和过氧化苯甲酸叔丁酯（TBPB）引发剂为例，TBPB 引发的共聚具有最大的温度上升率和压力上升率。在绝热失控的情况下，温度和压力随着 TBPB 浓度的增加而显著变化，这表明热失控的潜在风险很大。基于量热数据的动力学参数计算揭示了热失控机制。

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引用次数: 0

Correlation between activation energy and reaction temperature as observed in thermal analysis kinetics 热分析动力学中观察到的活化能与反应温度之间的相关性

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-20 DOI: 10.1016/j.tca.2024.179911

Sergey Vyazovkin

The activation energies (E) and temperatures (T) of a variety of chemical reactions are analyzed to reveal the following correlation: E(kJ/mol)=(35±12)+(0.46±0.04)T(°C). The correlation is statistically significant having the Pearson's coefficient of linear correlation 0.873. Consequently, 76 % of the observed variation in the activations energy is caused by the actual relationship between E and T, whereas only 24 % is attributed to chance. A statistically similar correlation is revealed for crystallization of glasses. In practice, such correlations can be used to estimate the initial E values in nonlinear optimization of kinetic models or to quickly check whether the experimental activation energies disagree excessively with the expected values. An attempt is made to identify the physical origins of the correlation.

通过分析各种化学反应的活化能 (E) 和温度 (T)，可以发现以下相关性：E(kJ/mol)=(35±12)+(0.46±0.04)T(°C).该相关性具有显著的统计学意义，皮尔逊线性相关系数为 0.873。因此，在观察到的活化能变化中，有 76% 是由 E 和 T 之间的实际关系引起的，只有 24% 是偶然因素。在统计上，玻璃的结晶也有类似的相关性。在实践中，这种相关性可用于估计动力学模型非线性优化中的初始 E 值，或用于快速检查实验活化能是否与预期值相差过大。本文试图找出相关性的物理根源。

引用次数: 0

Enhanced production of thiophenes, pyrroles, and olefines via a catalyst-assisted pyrolysis of oil shale 通过催化剂辅助热解油页岩提高噻吩、吡咯和烯烃的产量

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-19 DOI: 10.1016/j.tca.2024.179900

Zhaoyang Ren , Guojing Xu , Guangwei Geng , Junjie Wang , Zhenpeng Wang , Jian-Zheng Su , Xiang-Long Meng , Penglei Chen

Phosphotungstic acid/boehmite (PWA/B) is used to catalyze oil shale (OS) pyrolysis, where either the quality of thus-catalyzed pyrolyzates could be upgraded distinctly with regard to an evident removal of heteroatom-containing species and a remarkable enrichment in the content of hydrocarbons and short-chain aliphatic hydrocarbons, or the proportion of a number of valuable basic chemicals of extensive engineering/scientific interests, e.g., pyrroles, thiophenes, α-olefines and diolefines, could be enhanced substantially. We reveal that the density/acidity of Brønsted acids of PWA/B are larger/stronger than those of Lewis acids such that their collaborate-competition actions confer it with fascinating catalytic performances. Our work likely launches new opportunities for manufacturing value-added chemical/tecton or producing high-quality petroleum-like fuel using OS as feedstock, and it provides important guidance for the design and seeking of sophisticated catalyst for OS exploitation.

磷钨酸/沸石（PWA/B）可用于催化油页岩（OS）热解，经此催化的热解产物的质量可明显提高，含杂原子的物质明显去除，碳氢化合物和短链脂肪族碳氢化合物的含量显著增加、吡咯类、噻吩类、α-烯烃类和二烯烃类的比例可能会大幅提高。我们发现，PWA/B 的布氏酸密度/酸度比路易斯酸的密度/酸度更大/更强，因此它们的协同竞争作用使其具有迷人的催化性能。我们的工作可能会为以操作系统为原料生产高附加值化学品/涂料或高品质类石油燃料带来新的机遇，并为设计和寻求用于操作系统开发的先进催化剂提供重要指导。

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引用次数: 0

Exploration of the combustion characteristic based on the pyrolysis and combustion spectral analysis of single base propellant 基于单基推进剂热解和燃烧光谱分析的燃烧特性探索

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-16 DOI: 10.1016/j.tca.2024.179901

Le Wang , Huiming Sun , Quanwei Li , Bin Fei , Renming Pan , Xia Zhou

The pyrolysis and combustion of gunpowder are inseparable. To explore the risk characteristics of single base propellant, the pyrolysis kinetics and spectral information of single base propellant during combustion were studied in this work. Notably, with an increased heating rate, the exothermic peak shifts to higher temperatures, and the exothermic rate intensifies during the pyrolysis process, resulting in an incomplete reaction and the formation of residues. The reaction of single base propellant encompasses decomposition stage and multiple level reactions, it is phase boundary reaction mechanism. NO is generated firstly at 441.108 K and is identified as the most influential substance in facilitating the transition from pyrolysis to combustion. It causes intensified molecular chain breakage, CO, NH₃, H₂O, HCN, C_xH_y, NO, CO₂ are generated. The combustion process results in the destruction of the flocculent structure and amorphous regions within single base propellant, leading to a relatively smooth particle surface, reduced porosity, and structural collapse. Moreover, the combustion optical spectrum of single base propellant has a distinct characteristic absorptions at 589 nm, 767 nm, and 770 nm, corresponding to Na and K, respectively. The spectrals can be effectively discerned within 15 ms. During the from pyrolysis to combustion of the single base propellant, the reaction mechanism, spectral band and intensity provide valuable indicators for anticipating potential accidental combustion hazards.

火药的热解和燃烧密不可分。为了探究单基推进剂的危险特性，本研究对单基推进剂在燃烧过程中的热解动力学和光谱信息进行了研究。值得注意的是，随着加热速率的增加，放热峰向更高温度移动，热解过程中放热速率加剧，导致反应不完全并形成残留物。单基推进剂的反应包括分解阶段和多级反应，属于相界反应机理。NO 首先在 441.108 K 时生成，被认为是促进从热解向燃烧过渡的最有影响力的物质。它加剧了分子链的断裂，生成 CO、NH3、H2O、HCN、CxHy、NO 和 CO2。燃烧过程会破坏单基推进剂内部的絮状结构和无定形区域，导致颗粒表面相对光滑、孔隙率降低和结构坍塌。此外，单基推进剂的燃烧光学光谱在 589 纳米、767 纳米和 770 纳米处有明显的吸收特征，分别对应于 Na 和 K。这些光谱可在 15 毫秒内有效分辨。在单基推进剂从热解到燃烧的过程中，反应机制、光谱带和强度为预测潜在的意外燃烧危险提供了有价值的指标。

{"title":"Exploration of the combustion characteristic based on the pyrolysis and combustion spectral analysis of single base propellant","authors":"Le Wang , Huiming Sun , Quanwei Li , Bin Fei , Renming Pan , Xia Zhou","doi":"10.1016/j.tca.2024.179901","DOIUrl":"10.1016/j.tca.2024.179901","url":null,"abstract":"<div><div>The pyrolysis and combustion of gunpowder are inseparable. To explore the risk characteristics of single base propellant, the pyrolysis kinetics and spectral information of single base propellant during combustion were studied in this work. Notably, with an increased heating rate, the exothermic peak shifts to higher temperatures, and the exothermic rate intensifies during the pyrolysis process, resulting in an incomplete reaction and the formation of residues. The reaction of single base propellant encompasses decomposition stage and multiple level reactions, it is phase boundary reaction mechanism. NO is generated firstly at 441.108 K and is identified as the most influential substance in facilitating the transition from pyrolysis to combustion. It causes intensified molecular chain breakage, CO, NH<sub>3</sub>, H<sub>2</sub>O, HCN, C<sub>x</sub>H<sub>y</sub>, NO, CO<sub>2</sub> are generated. The combustion process results in the destruction of the flocculent structure and amorphous regions within single base propellant, leading to a relatively smooth particle surface, reduced porosity, and structural collapse. Moreover, the combustion optical spectrum of single base propellant has a distinct characteristic absorptions at 589 nm, 767 nm, and 770 nm, corresponding to Na and K, respectively. The spectrals can be effectively discerned within 15 ms. During the from pyrolysis to combustion of the single base propellant, the reaction mechanism, spectral band and intensity provide valuable indicators for anticipating potential accidental combustion hazards.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"743 ","pages":"Article 179901"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sustainable humification of food waste slurry through thermally activated persulfate oxidation 通过热激活过硫酸盐氧化技术实现厨余泥浆的可持续腐殖化

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-10 DOI: 10.1016/j.tca.2024.179898

Jun Zhang , Hanbang Wang , Qinglin Zheng , Jianhui Zhi , Lianghu Su

This study introduces a thermoanalytical approach utilizing sodium persulfate (PS) to expedite the humification of food waste (FW) through advanced oxidation processes (AOPs). The method harnesses heat-induced free radicals to break down complex organic compounds into simpler forms, leading to the formation of humic substances. We conducted an analysis of changes in soluble chemical oxygen demand (SCOD), dissolved organic carbon (DOC), ammonia nitrogen, soluble proteins, and sugars, employing advanced techniques such as three-dimensional fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM). The findings indicate that the activation of PS at 70 °C effectively increases SCOD and DOC levels, converts proteins into soluble forms, and enhances NH₄⁺-N content. This study, which focuses on the utilization of thermal methods, affirms that the thermal activation of persulfate (PS) significantly boosts the humification of food waste (FW), presenting a sustainable approach for waste management and resource recovery.

本研究介绍了一种利用过硫酸钠（PS）的热分析方法，通过高级氧化过程（AOPs）加速厨余垃圾（FW）的腐殖化。该方法利用热引起的自由基将复杂的有机化合物分解成更简单的形式，从而形成腐殖质。我们采用三维荧光光谱、傅立叶变换红外光谱和扫描电子显微镜等先进技术，分析了可溶性化学需氧量（SCOD）、溶解有机碳（DOC）、氨氮、可溶性蛋白质和糖类的变化。研究结果表明，在 70 °C 下活化 PS 能有效提高 SCOD 和 DOC 含量，将蛋白质转化为可溶形式，并提高 NH4+-N 含量。这项以热处理方法为重点的研究证实，过硫酸盐（PS）的热活化能显著提高食物垃圾（FW）的腐殖化程度，为垃圾管理和资源回收提供了一种可持续的方法。

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引用次数: 0

Molecular dynamics simulation of combustion reaction process and products of oxygen-containing functional groups in coal based on Machine Learning Potential 基于机器学习潜能的煤中含氧官能团燃烧反应过程及产物的分子动力学模拟

IF 3.1 2区化学 Q2 CHEMISTRY, ANALYTICAL

Thermochimica Acta

Pub Date : 2024-11-10 DOI: 10.1016/j.tca.2024.179891

Jinzhang Jia , Yumo Wu , Dan Zhao , Fengxiao Wang , Dongming Wang , Qiang Yang , Yinghuan Xing , Shan Lu

Oxygen-containing functional groups are the main heat source of coal spontaneous combustion, but their complex reaction pathways and microscopic mechanisms are still unclear. In this study, the molecular dynamics simulation of the composite combustion reaction model system with four oxygen-containing functional groups was conducted using the Machine Learning (ML) potential force field. The results showed that the stability order of these four oxygen-containing functional groups in the combustion reaction system is as follows: ‒OH < ‒COOH < ‒C‒O < ‒C = O. These simulation findings align with those obtained from in-situ FTIR experiments, thereby validating the accuracy of the ML potential force field. Notably, ‒C‒O exhibits the highest tendency for CO₂ conversion (58.57 %); ‒COOH displays the highest tendency for H₂O conversion (45.00 %); and ‒OH demonstrates the highest tendency for CO conversion (59.17 %). The essence of the oxidative combustion reaction pathway involving oxygen-containing functional groups lies in the heat accumulation resulting from the oxidative dehydrogenation effect.

含氧官能团是煤炭自燃的主要热源，但其复杂的反应途径和微观机理尚不清楚。本研究利用机器学习（ML）势力场对含有四个含氧官能团的复合燃烧反应模型体系进行了分子动力学模拟。结果表明，这四个含氧官能团在燃烧反应体系中的稳定顺序如下：-这些模拟结果与现场傅立叶变换红外实验的结果一致，从而验证了 ML 势场的准确性。值得注意的是，-C-O 对 CO2 的转化率最高（58.57%）；-COOH 对 H2O 的转化率最高（45.00%）；-OH 对 CO 的转化率最高（59.17%）。含氧官能团氧化燃烧反应途径的本质在于氧化脱氢效应产生的热量积累。

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