{"title":"Aqueous-phase reforming of model compounds of wet biomass to hydrogen on alumina-supported metal catalysts","authors":"Rohini S. Zambare, Prakash D. Vaidya","doi":"10.1002/kin.21704","DOIUrl":"10.1002/kin.21704","url":null,"abstract":"<p>Catalytic aqueous-phase reforming (APR) of wet biomass such as microalgae and activated sludge is a potential technique for the production of H<sub>2</sub>-rich gaseous products. In the present work, model compounds such as ethylene glycol, xylose and alanine were selected as representatives of the polyols, carbohydrates and proteins in wet biomass. APR trials were performed in a stirred batch reactor using commercial Pt/Al<sub>2</sub>O<sub>3</sub> and Ru/Al<sub>2</sub>O<sub>3</sub> catalysts. The reforming reactions were investigated at different conditions: temperature (T), 498 to 518 K, feed concentration, 1 to 5 wt. %, catalyst loading (ω), 2 to 6 kg/m<sup>3</sup>, and reaction time (t), 1 to 6 h. The commercial Pt/Al<sub>2</sub>O<sub>3</sub> catalyst exhibited higher reforming activity. The influence of reaction parameters on turnover frequency (TOF<sub>H₂</sub>), hydrogen yield (Y-H<sub>2</sub>) and carbon-to-gas conversion (C to G conversion) was studied. The values of TOF<sub>H₂</sub> for Pt/Al<sub>2</sub>O<sub>3</sub> were measured at T = 518 K, ω = 2 kg/m<sup>3</sup> and t = 3 h using 1 wt% feed and these values were 19.2, 4 and 6 1/min for ethylene glycol, xylose and alanine. The values of TOF<sub>H₂</sub> over Ru/Al<sub>2</sub>O<sub>3</sub> under identical conditions were: ethylene glycol–12.4, xylose–1.4 and alanine–5.4 1/min. The activation energies for H<sub>2</sub> production from ethylene glycol, xylose and alanine over Pt/Al<sub>2</sub>O<sub>3</sub> and Ru/Al<sub>2</sub>O<sub>3</sub> catalysts were determined. APR of the mixture of model compounds was also studied over laboratory-made Pt/Al<sub>2</sub>O<sub>3</sub> and Ru/Al<sub>2</sub>O<sub>3</sub> catalysts at the optimum reaction conditions. Thus, this work has provided crucial insights into the production of H<sub>2</sub> from model compounds of wet biomass using Al<sub>2</sub>O<sub>3</sub>-supported catalysts.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 5","pages":"265-278"},"PeriodicalIF":1.5,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138957937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Automatic mechanism generation for the combustion of advanced biofuels: A case study for diethyl ether","authors":"Christian A. Michelbach, Alison S. Tomlin","doi":"10.1002/kin.21705","DOIUrl":"10.1002/kin.21705","url":null,"abstract":"<p>Advanced biofuels have the potential to supplant significant fractions of conventional liquid fossil fuels. However, the range of potential compounds could be wide depending on selected feedstocks and production processes. Not enough is known about the engine relevant behavior of many of these fuels, particularly when used within complex blends. Simulation tools may help to explore the combustion behavior of such blends but rely on robust chemical mechanisms providing accurate predictions of performance targets over large regions of thermochemical space. Tools such as automatic mechanism generation (AMG) may facilitate the generation of suitable mechanisms. Such tools have been commonly applied for the generation of mechanisms describing the oxidation of non-oxygenated, non-aromatic hydrocarbons, but the emergence of biofuels adds new challenges due to the presence of functional groups containing oxygen. This study investigates the capabilities of the AMG tool Reaction Mechanism Generator for such a task, using diethyl ether (DEE) as a case study. A methodology for the generation of advanced biofuel mechanisms is proposed and the resultant mechanism is evaluated against literature sourced experimental measurements for ignition delay times, jet-stirred reactor species concentrations, and flame speeds, over conditions covering <i>φ</i> = 0.5–2.0, <i>P</i> = 1–100 bar, and <i>T</i> = 298–1850 K. The results suggest that AMG tools are capable of rapidly producing accurate models for advanced biofuel components, although considerable upfront input was required. High-quality fuel specific reaction rates and thermochemistry for oxygenated species were required, as well as a seed mechanism, a thermochemistry library, and an expansion of the reaction family database to include training data for oxygenated compounds. The final DEE mechanism contains 146 species and 4392 reactions and in general, provides more accurate or comparable predictions when compared to literature sourced mechanisms across the investigated target data. The generation of combustion mechanisms for other potential advanced biofuel components could easily capitalize on these database updates reducing the need for future user interventions.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 4","pages":"233-262"},"PeriodicalIF":1.5,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/kin.21705","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138965915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nadia Sebbar, Henning Bockhorn, Dimosthenis Trimis
{"title":"Oxidation of the 1-naphthyl radical C10H7• with oxygen: Thermochemistry, kinetics, and possible reaction pathways","authors":"Nadia Sebbar, Henning Bockhorn, Dimosthenis Trimis","doi":"10.1002/kin.21702","DOIUrl":"10.1002/kin.21702","url":null,"abstract":"<p>The reaction of the 1-naphthyl radical C<sub>10</sub>H<sub>7</sub>• (A2•) with molecular (<sup>3</sup>O<sub>2</sub>) and atomic oxygen, as part of the oxidation reactions of naphthalene, is examined using ab-initio and DFT quantum chemistry calculations. The study focuses on pathways that produce the intermediate final products CO, phenyl and C<sub>2</sub>H<sub>2</sub>, which may constitute a repetitive reaction sequence for the successive diminution of six-membered rings also in larger polycyclic aromatic hydrocarbons. The primary attack of <sup>3</sup>O<sub>2</sub> on the 1-naphthyl radical leads to a peroxy radical C<sub>10</sub>H<sub>7</sub>OO• (A2OO•), which undergoes further propagation and/or chain branching reactions. The thermochemistry of intermediates and transition state structures is investigated as well as the identification of all plausible reaction pathways for the A2• + O<sub>2</sub> / A2• + O systems. Structures and enthalpies of formation for the involved species are reported along with transition state barriers and reaction pathways. Standard enthalpies of formation are calculated using ab initio (CBS-QB3) and DFT calculations (B3LYP, M06, APFD). The reaction of A2• with <sup>3</sup>O<sub>2</sub> opens six main consecutive reaction channels with new ones not currently considered in oxidation mechanisms. The reaction paths comprise important exothermic chain branching reactions and the formation of unsaturated oxygenated hydrocarbon intermediates. The primary attack of <sup>3</sup>O<sub>2</sub> at the A2• radical has a well depth of some 50 kcal mol<sup>−1</sup> while the six consecutive channels exhibit energy barriers below the energy of the A2• radical. The kinetic parameters of each path are determined using chemical activation analysis based on the canonical transition state theory calculations. The investigated reactions could serve as part of a comprehensive mechanism for the oxidation of naphthalene. The principal result from this study is that the consecutive reactions of the A2• radical, viz. the channels conducting to a phenyl radical C<sub>6</sub>H<sub>5</sub>•, CO<sub>2</sub>, CO (which oxidized to CO<sub>2</sub>) and C<sub>2</sub>H<sub>2</sub> are by orders of magnitude faster than the activation of naphthalene by oxygen (A2 + O<sub>2</sub> → A2• + HO<sub>2</sub>).</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 4","pages":"210-232"},"PeriodicalIF":1.5,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/kin.21702","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138574597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hong-Quan Do, Benoîte Lefort, Zeynep Serinyel, Luis LeMoyne, Guillaume Dayma
{"title":"Comparative study of the high-temperature auto-ignition of cyclopentane and tetrahydrofuran","authors":"Hong-Quan Do, Benoîte Lefort, Zeynep Serinyel, Luis LeMoyne, Guillaume Dayma","doi":"10.1002/kin.21703","DOIUrl":"10.1002/kin.21703","url":null,"abstract":"<p>Cyclopentane (C<sub>5</sub>H<sub>10</sub>) and tetrahydrofuran (C<sub>4</sub>H<sub>8</sub>O) are both five-membered ring compounds. The present study compares the auto-ignition of cyclopentane and tetrahydrofuran in a high-pressure shock-tube (20 atm). Twelve different mixtures were investigated at two different fuel initial mole fractions (1% and 2%): at X<sub>fuel</sub> = 1%, three equivalence ratios, kept constant between cyclopentane and tetrahydrofuran, were studied (0.5, 1, and 2), whereas three X<sub>fuel</sub>/X<sub>O2</sub> were investigated when X<sub>fuel</sub> = 2%. A detailed kinetic mechanism was developed to reproduce cyclopentane and tetrahydrofuran auto-ignition. The agreement between our experimental results and the modeling is very good. This mechanism was used to explain the similarities and differences observed between cyclopentane and tetrahydrofuran auto-ignition.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 4","pages":"199-209"},"PeriodicalIF":1.5,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138568463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Esterification of butyric acid with n-butanol: Kinetic study using experimental data and modeling","authors":"Ashutosh Kumar Pathak, Madhusree Kundu","doi":"10.1002/kin.21701","DOIUrl":"10.1002/kin.21701","url":null,"abstract":"<p>Present study involves the investigation of the esterification kinetics between butyric acid and <i>n</i>-butanol. This reaction was conducted in a batch reactor, utilizing homogeneous methanesulfonic acid (MSA) catalyst. Response surface methodology (RSM) was conducted prior to the kinetic study using “Design Expert; version-11.0” for finding the causal factors influencing the conversion of butyric acid. Most important factors identified with their limits against conversions (during optimization of the process using RSM) were taken up to critically analyze the effect of them on butyric acid conversion. Concentration and activity-based model of the process were proposed assuming second order reversible reaction scheme using homogeneous MSA catalyst. During the study of non-ideal behavior of the system, UNIFAC model was adapted for assessing the activity coefficients of species present in equilibrated liquid phase. Experimental data were used to evaluate kinetic and thermodynamic parameters such as rate constants, activation energy, enthalpy, and entropy of the system. The endothermic nature of esterification was confirmed by positive value of enthalpy obtained. The effect of various levels of causal variables like temperature (60–90°C), catalyst concentration (0.5–1.5 wt.%), and molar ratio of <i>n</i>-butanol to butyric acid (1–3) on conversion kinetics of butyric acid was investigated during transient and equilibrium phase of the reaction. It has been observed that molar ratio of butanol to butyric acid has the highest influence on the conversion. The rate equation derived offered a kinetic and thermodynamic framework to the generated data. It also exhibits a notable degree of conformity of predicted data to the experimental ones and effectively characterizes the system across different reaction temperatures, reactant molar ratio, and catalyst concentration.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 4","pages":"188-198"},"PeriodicalIF":1.5,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138520589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sara Majid, Khuram Shahzad Ahmad, Ibrahim A. A., Muhammad Azad Malik
{"title":"Decoding Coumaphos: Tracing its journey in the lithosphere via degradation mechanisms and assessing sorption proficiency through kinetics study","authors":"Sara Majid, Khuram Shahzad Ahmad, Ibrahim A. A., Muhammad Azad Malik","doi":"10.1002/kin.21699","DOIUrl":"10.1002/kin.21699","url":null,"abstract":"<p>The fate of Coumaphos in the environment was evaluated through meticulous emulation and analysis of the intricate pedospheric matrices. The fate-determinative investigations entailed a meticulous examination of Coumaphos's behavior, encompassing adsorption and desorption characteristics and its decomposition rate via hydrolysis, photolysis, and intrinsic biological degradation in soil. The interactions between Coumaphos molecules and soils were found to be robust, with physiosorption being the predominant mode of interaction. Thermodynamic analysis, based on the negative values of Gibbs free energy (−23,569 to −15,798 kJ/mol), indicated exothermic and spontaneous adsorption processes. The highest adsorption capacity (<i>K</i><sub><i>d</i>(<i>ads</i>)</sub> = 34.97 μg/mL) was observed in soils with a notable organic matter content (1.99%), exhibiting a C-type isotherm that was confirmed through linear and Freundlich models. Analytical techniques such as ultraviolet-visible spectrophotometry and gas chromatography-mass spectrometry were employed to determine the fate of Coumaphos in soil matrices. The minimum half-lives of Coumaphos in hydrolysis, biodegradation, and photolysis experiments were 203, 52, and 69 days, respectively. These findings highlight the strong affinity of Coumaphos for the selected agricultural soils, indicating limited potential for transformation. Moreover, findings highlight the potential for further optimization of these degradative routes to devise practical strategies for environmental remediation utilizing natural processes.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 4","pages":"171-187"},"PeriodicalIF":1.5,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135222284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Temperature dependent rate constant for the reaction of H-atoms with carbonyl sulfide","authors":"Yuri Bedjanian","doi":"10.1002/kin.21700","DOIUrl":"10.1002/kin.21700","url":null,"abstract":"<p>The kinetics of the reaction of H-atom with carbonyl sulfide (OCS) has been investigated at nearly 2 Torr total pressure of helium over a wide temperature range, <i>T</i> = 255–960 K, using a low-pressure discharge flow reactor combined with an electron impact ionization quadrupole mass spectrometer. The rate constant of the reaction H + OCS → SH + CO (1) was determined under pseudo-first order conditions, monitoring the kinetics of H-atom consumption in excess of OCS, <i>k</i><sub>1</sub> = 6.6 × 10<sup>−13</sup> × (<i>T</i>/298)<sup>3</sup> × exp(−1150/<i>T</i>) cm<sup>3</sup> molecule<sup>−1</sup> s<sup>−1</sup> (with estimated total uncertainty on <i>k</i><sub>1</sub> of 15% at all temperatures). Current measurements of <i>k</i><sub>1</sub> at intermediate temperatures (520–960 K) appear to reconcile previous high and low temperature data and allow the above expression for <i>k</i><sub>1</sub> to be recommended for use in the extended temperature range between 255 and 1830 K with a conservative uncertainty of 20%.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 3","pages":"162-167"},"PeriodicalIF":1.5,"publicationDate":"2023-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136135082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Kinetics and mechanism of dissolved organic phosphorus (DOP) digestion by the UV/O3 process","authors":"Jialong Zhu, Kaixuan Fang, Mengdi Zhang, Huixuan Chen, Mengfei Zhou, Xiaofang Sun","doi":"10.1002/kin.21695","DOIUrl":"10.1002/kin.21695","url":null,"abstract":"<p>In this study, the kinetics and mechanism of UV/O<sub>3</sub> synergistic oxidative digestion of dissolved organic phosphorus (DOP) were investigated, focusing on the ozone direct oxidation and hydroxyl radical oxidation parts of glufosinate and triphenyl phosphate (TPhP). The p-chlorobenzoic acid (p-CBA) was selected as the probe compound, and two kinds of reaction kinetic models were proposed by competitive kinetic method with <i>R<sub>ct</sub></i> according to the different scale of rate constants of hydroxyl radical oxidation. Under the condition of weakly alkaline (pH = 9.0) and weakly acidic environment (pH = 5.0), the second-order rate constants of glufosinate and TPhP was determined indirectly to be <i>k</i>o<sub>3/glufosinate</sub> = (2.903 ± 0.247)M<sup>−1</sup>s<sup>−1</sup> and <i>k</i>o<sub>3/TPhP</sub> = (3.307 ± 0.204) M<sup>−1</sup>s<sup>−1</sup> by ozone direct oxidation, and <i>k</i><sub>·OH/glufosinate</sub> = (1.257 ± 1.031) × 10<sup>9</sup> M<sup>−1</sup>s<sup>−1</sup> and <i>k</i><sub>·OH/TPhP</sub> = (7.120 × 10<sup>8</sup> ± 0.963) M<sup>−1</sup>s<sup>−1</sup> by hydroxyl radical oxidation, respectively. The comparison of the contribution levels of the two parts to the digestion process showed that the contribution levels in the digestion of glufosinate and TPhP processes both the contribution of ·OH were higher than those of ozone, 86.3% and 72.6%, respectively.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 3","pages":"150-161"},"PeriodicalIF":1.5,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135888294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria E. Angelaki, Manolis N. Romanias, James B. Burkholder, Vassileios C. Papadimitriou
{"title":"Rate coefficients for the gas-phase OH + furan (C4H4O) reaction between 273 and 353 K","authors":"Maria E. Angelaki, Manolis N. Romanias, James B. Burkholder, Vassileios C. Papadimitriou","doi":"10.1002/kin.21697","DOIUrl":"10.1002/kin.21697","url":null,"abstract":"<p>Rate coefficients, <i>k</i><sub>1</sub>, for the gas-phase OH radical reaction with the heterocyclic ether C<sub>4</sub>H<sub>4</sub>O (1,4-epoxybuta-1,3-diene, furan) were measured over the temperature range 273–353 K at 760 Torr (syn. air). Experiments were performed using: (i) the photochemical smog chamber THALAMOS (thermally regulated atmospheric simulation chamber, IMT NE, Douai-France) equipped with Fourier Transform Infrared (FTIR) and Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) detection methods and (ii) a photochemical reactor coupled with FTIR spectroscopy (PCR, University of Crete, Greece). <i>k</i><sub>1</sub>(273–353 K) was measured using a relative rate (RR) method, in which the loss of furan was measured relative to the loss of reference compounds with well-established OH reaction rate coefficients. <i>k</i><sub>1</sub>(273–353 K) was found to be well represented by the Arrhenius expression (1.30 ± 0.12) × 10<sup>−11</sup> exp[(336 ± 20)/T] cm<sup>3</sup> molecule<sup>−1</sup> s<sup>−1</sup>, with <i>k</i><sub>1</sub>(296 K) measured to be (4.07 ± 0.32) × 10<sup>−11</sup> cm<sup>3</sup> molecule<sup>−1</sup> s<sup>−1</sup>. The <i>k</i><sub>1</sub>(296 K) and pre-exponential quoted error limits are 2σ and include estimated systematic errors in the reference rate coefficients. The observed negative temperature dependence is consistent with a reaction mechanism involving the OH radical association to a furan double bond. Quantum mechanical molecular calculations show that OH addition to the <i>α</i>-carbon (Δ<i>H</i><sub>r</sub>(296 K) = −121.5 kJ mol<sup>−1</sup>) is thermochemically favored over the <i>β</i>-carbon (Δ<i>H</i><sub>r</sub>(296 K) = −52.9 kJ mol<sup>−1</sup>) addition. The OH-furan adduct was found to be stable over the temperature range of the present measurements. Maleic anhydride (C<sub>4</sub>H<sub>2</sub>O<sub>3</sub>) was identified as a minor reaction product, 3% lower-limit yield, demonstrating a non-ring-opening active reaction channel. The present results are critically compared with results from previous studies of the OH + furan reaction rate coefficient. The infrared spectrum of furan was measured as part of this study and its estimated climate metrics are reported.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 3","pages":"119-130"},"PeriodicalIF":1.5,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/kin.21697","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135995909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A detailed reaction mechanism for hexamethyldisiloxane combustion via experiments and ReaxFF molecular dynamics simulations","authors":"Yaosong Huang, Hao Chen","doi":"10.1002/kin.21698","DOIUrl":"10.1002/kin.21698","url":null,"abstract":"<p>Hexamethyldisiloxane (HMDSO) is one of the main impurities in the syngas produced from sewage and landfill plants. In order to utilize this syngas or control the characteristics of the generated silica particles, it is crucial to understand the chemical kinetics of HMDSO combustion. This study investigated the process of HMDSO combustion using synchrotron radiation mass spectrometry (SRMS), gas chromatography (GC), and ReaxFF molecular dynamics simulations. First, the force field used for ReaxFF simulation was validated by comparing the energies of different bond lengths, bond angles, and dihedral angles with the ones from DFT calculations. Good agreements were found. Then, ReaxFF simulations of HMDSO combustion with this force field were conducted under various conditions, which include different equivalence ratios (0.67, 1.0, and 1.5) and temperatures ranging from 2000 to 3500 K. The oxidation characteristics of HMDSO were analyzed, including the evolution of gas products and particle formation. Finally, based on the results from experiments and ReaxFF simulations, the reaction pathways, reaction lists, and reaction kinetics data during HMDSO combustion were obtained. A detailed reaction mechanism was proposed and validated by applying it in modeling the H<sub>2</sub>/HMDSO/O<sub>2</sub> combustion systems. The temperature and part of the gas products such as CO and CO<sub>2</sub> as well as SiO could be well predicted.</p>","PeriodicalId":13894,"journal":{"name":"International Journal of Chemical Kinetics","volume":"56 3","pages":"131-149"},"PeriodicalIF":1.5,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135995768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}