With the increasingly prominent environmental problems and depletion of light petrochemical resources, the clean utilization of heavy oil has become the research focal area. The hydrodenitrogenation (HDN) experiments and kinetics of full‐range middle‐low temperature coal tar (MLCT) was studied on a fixed‐bed reactor with a Ni‐Mo/γ‐Al2O3 catalyst. Two kinds of three‐lumped kinetic models (K1 and K1

High‐pressure shock tube ignition delay data are essential for fuel characterization and for the validation and optimization of chemical–kinetic models. Therefore, it is crucial that realistic measurement conditions are considered in modeling. Furthermore, an accurate uncertainty quantification for experimental data is the basis for evaluation of the predictive reliability of chemical–kinetic models

The multichannel reaction of excited singlet oxygen atom with ethanol, O(1D) + C2H5OH (1), was studied in a photolysis flow reactor coupled with mid‐infrared Faraday rotation spectroscopy (FRS) and UV‐IR direct absorption spectroscopy (DAS) at 297 K with reactor pressures of 60, 120, and 150 Torr (bath He). The excited singlet oxygen atom was generated through the photolysis of O3 at 266 nm. The photon

Vibrational excitation of the H2O, HOD, and D2O product molecules from the reactions of OH and OD radicals with CH3SH, CH3C(O)SH, (CH3)3CSH, H2S, and CH3SCH3 was determined by modeling the infrared emission spectra using a renovated and extended set of model spectroscopic bands. Using the deuterated reactant, CH3SD, it was possible to separate spectra of abstraction from C‐ and S‐sites, which allowed

We established a kinetic model (the UT2017 model) for chemical vapor deposition of silicon carbide (SiC) from methyltrichlorosilane (CH3SiCl3, MTS)/H2, and quantitatively identified CH2SiCl3 as one of the SiC film‐forming species. In a previous study, we established a kinetic model (the UT2014 model), which reproduced the overall decomposition of MTS, but had not validated it in terms of radicals.

An in depth understanding of the kinetics of the decomposition of plastic mixtures is necessary to enhance chemical recycling approaches, in particular by pyrolysis. The fact that plastic waste is usually composed of mixtures of plastics constitutes a hindrance for secondary recycling but may not be a particular difficulty for tertiary recycling. In this study, an analysis of the thermal degradation

Spectrophotometric analysis was applied to check the kinetics of bromothymol blue (BTB) oxidation by alkaline permanganate at constant ionic strength 0.2 mol dm−3. The redox reaction was observed to proceed through two independently distinct, detectable steps. The first step coexists with the formation of intermediate complexes involving transient species relatively quickly of the blue hypomanganate(V)

A comprehensive study on the reaction of H + C3H6 has been conducted in order to clarify the temperature and pressure dependence of product branching. Site‐specific rate of addition of a hydrogen atom to the center carbon is measured by a comparative method for the evolutions of H atoms behind reflected shock waves. The rate constant for the addition to the center carbon can be given by ln(k1‐2/cm

In this article, the enzyme kinetic activity of Mucor javanicus lipase (MJL) has investigated via hydrolysis of p‐nitrophenyl acetate (PNPA) in different pH environment, cationic surfactants, and inorganic salts. The influence of hydrophilicity has been studied in the presence of cationic cetyltrimethylammonium bromide (CTAB), cetyltriphenylphosphonium bromide (CTPB), and cetyldimethylethanolammonium

Hydroxyapatite (HAP) is one of the most attractive calcium phosphates which is used for different applications. While HAP has been mostly synthesized using wet methods, recently solid‐state synthesis methods have attracted more attention. Many efforts have been made to better understand the solid‐state synthesis mechanism. In this study, the kinetics of the solid‐state reaction between hydroxide calcium

Cysteamine (CA) and d‐penicillamine (Pen) are the thiol‐containing drugs and good antioxidants. Their reactions with a cisplatin Pt(IV) prodrug cis‐diamminetetrachloroplatinum(IV) (cis‐[Pt(NH3)2Cl4]) were investigated by use of rapid scan, stopped‐flow, and mass spectral techniques. The kinetic traces are biphasic in nature, encompassing a faster reduction of cis‐[Pt(NH3)2Cl4] to cisplatin followed

Peroxy (RO2) radicals derived from short‐chain alkanes were detected by an improved technique involving combined fluorescence assay by gas expansion and laser‐induced fluorescence (FAGE‐LIF) and chemical conversion under atmospheric conditions (298 K and 1 bar). The suitability of the system for measuring RO2 kinetics was tested using the CH3O2 + NO2 + M CH3O2NO2 + M reaction. CH3O2 radicals were generated

A catalase from a novel source Sechium edule (squash) has been purified to homogeneity using ammonium sulfate fractional precipitation, dialysis, and anion exchange chromatography on Diethylaminoethyl (DEAE) cellulose in sodium acetate buffer pH 6.0. The purity of the enzyme was analyzed by SDS‐PAGE. The molecular weight of the enzyme using the SDS‐PAGE method was found to be 55 kDa with specific activity

Toluene alkylation with methanol could serve as a green “molecular engineering” to produce para‐xylene (PX). However, the conversion and para‐selectivity are the key index to the application of this technology. Based on the reaction network and kinetics, the fixed‐bed models were introduced to analyze and optimize the para‐selectivity at reactor level. After the validation with the experimental results

A comprehensive study of the properties and reactivity of ethyl(S)‐lactate has been conducted. The conformational landscape, the enthalpy of formation of the ground state,  kJ mol−1, the thermochemistry (entropy, specific heat, enthalpy function), adiabatic ionization energy, and the single bond dissociation energies are also mapped out. Unimolecular elimination reactions leading to water and ethyl

H2O formation during thermal decomposition of isopropanol was measured behind reflected shock waves at temperatures ranging from 1127 to 1621 K at an average pressure of 1.42 atm using a laser absorption technique. Of the five modern chemical kinetics models used to compare the H2O time histories, the model from Li et al (Combust. Flame 2019;207:171‐185) showed the best overall agreement. Sensitivity

Chemical kinetic models of gasoline, jet, and diesel fuels and their mixtures with bioderived fuels are needed to assess fuel property effects on efficiency, emissions, and other performance metrics in internal combustion and gas turbine engines. As these real fuels have too many fuel components to be included in a chemical kinetic model, surrogate fuels containing fewer components are used to represent

Oxiranes are a class of cyclic ethers formed in abundance during low‐temperature combustion of hydrocarbons and biofuels, either via chain‐propagating steps that occur from unimolecular decomposition of β‐hydroperoxyalkyl radicals (β‐̇QOOH) or from reactions of HOȮ with alkenes. Ethyloxirane is one of four alkyl‐substituted cyclic ether isomers produced as an intermediate from n‐butane oxidation. While

The present research investigates the kinetics of ultrasound‐assisted synthesis of dibutyl maleate using a heterogeneous catalyst (Amberlyst‐15) in solvent‐free system. Reaction parameters were optimized based on conversion by varying the various parameters such as n‐butanol to maleic acid mole ratio, temperature, molecular sieves, catalyst loading, power, and duty cycle. Optimization of parameters

We have used the single‐pulse shock tube technique with postshock GC/MS product analysis to investigate the mechanism and kinetics of the unimolecular decomposition of isopropanol, a potential biofuel, and of its reaction with H atoms at 918‐1212 K and 183‐484 kPa. Experiments employed dilute mixtures in argon of isopropanol, a radical scavenger, and, for H‐atom studies, two different thermal precursors

Oxiranes are a class of cyclic ethers formed in abundance during low‐temperature combustion of hydrocarbons and biofuels, either via chain‐propagating steps that occur from unimolecular decomposition of β‐hydroperoxyalkyl radicals (β‐̇QOOH) or from reactions of HȮO with alkenes. The cis‐ and trans‐isomers of 2,3‐dimethyloxirane are intermediates of n‐butane oxidation, and while rate coefficients for

This study deals with the trichloroisocyanuric acid (TCCA) interactions with carboxamides like formamide (FMA), N,N′‐dimethyl formamide (DMF), and N,N′‐dimethyl acetamide (DMA) interactions during the nitration of heterocyclic compounds (HC) like pyrrole and indole in the presence of excess of [NaNO2] over the concentrations of all other reactants. All the reactions were performed in aqueous acetonitrile

The kinetics of the reactions of F atoms with hydrogen and deuterium has been studied in a discharge flow reactor combined with an electron impact ionization quadrupole mass spectrometer at nearly 2 Torr total pressure of helium and in the temperature range 220‐960 K. The rate constant of the reaction F + H2 → HF + H (1) was determined using both relative rate method (using reaction F + Br2 as a reference)

We performed stochastic and deterministic calculations to study simple bimolecular chemical kinetics with a neighborhood, necessary for solid‐state and viscous medium reactions. Regarding the standard deterministic method using ordinary differential equations (ODEs) to describe a bimolecular reaction with the neighborhood, we established a comparison that indicates, in this method, an implicit diffusion

The pyrolysis of 1‐pentene was investigated in a flow reactor over temperatures of 900–1300 K and pressures of 0.04 and 1 atm using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV‐PIMS). Pyrolysis products, especially radicals and cyclic compounds, were identified, and their mole fraction profiles were quantified. A detailed kinetic model of 1‐pentene combustion was developed

Kinetic data is an elegant tool to quantitatively assess structure—reactivity correlation of organic substrates in reactions and is immaculate if endorsed with complementary information. Halogenations of aromatic substrates in aqueous medium are rapid reactions necessitating special techniques for their study. Their rates depend on nature of the reagents, nucleophilicity of the substrates, and steric

Nonequilibrium plasma has a great potential in the lean combustion of gasoline engines. However, fundamental studies on plasma‐assisted combustion on gasoline components are limited. In the present study, Low‐temperature oxidation behaviors for n‐heptane and iso‐octane in a plasma flow reactor were investigated. Species measurements were performed at room temperature and low pressure of 40 mbar using

The reaction of CH3 + HCNO was theoretically studied by both density functional theory and molecular orbital calculations and analyzed by quantum statistical methods. The potential energy surface was constructed at the UCCSD(T)//B3LYP/6‐311++G(3df,2p) + ZPE level. Four entrance channels are opened relating to the interaction of the CH3 radical with each of the four atoms of the HCNO molecule, giving

cis‐Pinane, the hydrogenation product of pinene, is a key chemical intermediate and its production is an important forest chemical process. In this study, α‐pinene was hydrogenated using a nickel‐supported aluminophosphate catalyst (Ni/APO‐PT) in the batch mode of operation. The pore structure of the catalyst was characterized, the process parameters were studied, the hydrogenation process was optimized

Higher alcohol synthesis (HAS) from syngas is one of the most promising approaches to produce fuels and chemicals. Our recent investigation on HAS showed that potassium‐promoted cobalt‐molybdenum sulfide is an effective catalyst system. In this study, the intrinsic kinetics of the reaction were studied using this catalyst system under realistic conditions. The study revealed the major oxygenated products

The reaction of Br atoms with toluene was investigated by employing various quantum chemical methods and statistical rate theory calculations. Various composite methods such as CBS‐QB3, G3, and G4 were used to obtain the energy profiles of the Br + toluene reaction. Further single‐point calculations of the stationary points were performed at the CCSD(T)/cc‐pV(D,T)Z level of theory using B3LYP/cc‐pVTZ

This work presents a comprehensive kinetic modeling study of the pyrolysis and oxidation of chloromethane. Theoretical calculations were performed for the decomposition reaction CH3Cl + M = CH3 + Cl + M and for a set of relevant H‐abstraction reactions (CH3Cl + R, R = Cl, Ḣ, ȮH, HȮ2, O2, Ö, ĊH3, Ċ2H3, Ċ2H5; CH4 + Cl, C2H6 + Cl, C2H4 + Cl, C2H2 + Cl). Comparison with previous experimental or theoretical

Nitration of aromatic compounds and heterocycles in mixed acid environment is one of the regularly performed large‐scale reactions in the chemical industry. Although the reaction mechanism of nitration of aromatics in mixed acid is well established, the development of a methodology for the evaluation of kinetics of exothermic aromatic nitrations in a simplified and accurate way is necessary. Here we

The kinetics of hydroformylation of 1‐decene has been studied in an aqueous biphasic medium using a water‐soluble Rh‐sulfoxantphos catalyst in the presence of N‐methyl pyrrolidone as a cosolvent at 383‐403 K. The rate was found to be first order, with concentrations of catalyst and olefin and partial order, with concentrations of hydrogen in the liquid phase. The plot of rate versus excess ligand and

Using methods of chemical kinetics and quantum modeling, we investigated the mechanism by which base catalysts affect the regioselectivity of the ring opening of 2‐(chloromethyl)oxirane by benzoic acid. The model reaction was carried out using 2‐(chloromethyl)oxirane as both reagent and solvent at temperatures of 303‐333 K. Rate constants and activation parameters of the ring opening were determined

Electronic waste (e‐waste) contains metallic values that can be recovered by hydrometallurgical methods. This investigation addresses the leaching kinetics of e‐waste for the recovery of copper in H2SO4‐H2O2 media with the objective of determining the rate‐controlling step in monosize particle systems. The results are then used to develop a kinetic model for copper dissolution in multisize particle

A prerequisite for the generation of detailed fundamental kinetic models is the availability of accurate thermodynamic properties. To address the scarcity of accurate experimental data, theoretical calculations can be used. The accuracy of these quantum chemistry methods for determination of thermodynamic properties can be improved by making use of empirical correction methods, such as the isodesmic

A new reaction mechanism for the glycerol chlorination is proposed. This mechanism is based on theoretical calculations within density functional theory combined with polarizable continuum model . Two possibilities were investigated, the first is the SN2 chlorination forming mono‐ and dichlorinated products and the second one is through an ester intermediate formed by glycerol esterification in the

In this work, we propose the first Integral method for the Combined Kinetic Analysis (ICKA) of solid‐state reactions typically performed in a thermogravimetric analyzer. The ICKA method prevents the systematic inaccuracies inherent to all the differential methods, including the standard CKA method. Two main achievements have been made for implementing the method: (1) the most accurate approximation

In the context of better understanding pollutant formation from internal combustion engines, new experimental speciation data were obtained in a high‐pressure jet‐stirred reactor for the oxidation of three molecules, which are considered in surrogates of diesel fuel, n‐heptane, ethylbenzene, and n‐butylbenzene. These experiments were performed at pressures up to 10 bar, at temperatures ranging from

Previously, master equation (ME) simulations using semiclassical transition state theory (SCTST) and high‐accuracy extrapolated ab initio thermochemistry (HEAT) predicted rate constants in excellent agreement with published experimental data over a wide range of pressure and temperatures ≳250 K, but the agreement was not as good at lower temperatures. Possible reasons for this reduced performance are

Rate coefficients for the reactions of OH with n, s, and iso‐butanol have been measured over the temperature range 298 to ∼650 K. The rate coefficients display significant curvature over this temperature range and bridge the gap between previous low‐temperature measurements with a negative temperature dependence and higher temperature shock tube measurements that have a positive temperature dependence

Anatase TiO2, a widely used semiconductor metal oxide support, was tested for biomimetic carbonic anhydrase activity catalyzing the reversible hydration of CO2 to bicarbonate ions. Owing to superior photocatalytic response of nanoclusters of TiO2 and its apparent role in catalyzing CO2 hydration, (TiO2)15 nanocluster was tested for the reaction using density functional theory calculations. Free energy

We present new groups and group values for the gas‐phase thermochemistry of ethers, polyethers, and acetals suited for combustion modeling. Our investigation comprises fuel species, their primary radicals, peroxy radicals, and hydroperoxide species. In total, 45 species are used for the parameterization of 14 groups, six of which are newly introduced here. Presently, calculated thermochemistry at the

Quantum chemical calculations were used to investigate the mechanism and kinetics of the reaction of XO (X = Cl, Br) radicals with linear C2 to C4 alkenes. Two reaction routes, namely, addition and H‐abstraction, were investigated as part of the XO‐radical initiated degradation of these alkenes. Energies and structural parameters were obtained at the CCSD(T)/CBS//M062x/cc‐pVTZ level of theory, and

Oxidation of the iodide ion is an important facet of the solar cells such as perovskite solar cells and dye‐sensitized solar cells. The rate of reaction undoubtedly depends upon several factors. Such parameters include reaction media, electrolyte, and the nature of solvents, and electrolyte. If these factors are optimized then the rate of the reaction can be controlled and could be used to get the

The thermodynamic and kinetic investigation for the reaction of ethylperoxy radical (CH3CH2OO•) with ethanol (CH3CH2OH) was studied computationally with variational transition state theory. The geometry optimization calculations showed that both the reactants have two conformers. The energetics and thermodynamic properties were calculated using the G4 composite method. The results showed that the abstraction

The current work presents new experimental autoignition and speciation data on the two cis‐hexene isomers: cis‐2‐hexene and cis‐3‐hexene. The new data provide insights on the effects of carbon‐carbon double bond location and stereoisomeric structures on ignition delay times and reaction pathways for linear hexene isomers. Experiments were performed using the University of Michigan rapid compression

The mechanism of initial decomposition of energetic compound is crucial to understand the heat release efficiency, impact sensitivity, toxic emission, and so on. In the present study, we progressively explored the thermodynamic and kinetic features of the decomposition of LLM‐105, or 2,6‐diamino‐3,5‐dinitropyrazine‐1‐oxide, a kind of nitro compound in energetic materials using theoretical calculations

The cover image is based on the Article Influence of the double bond position in combustion chemistry of methyl butene isomers: A shock tube and laser absorption study by Farhan Arafin et al., https://doi.org/10.1002/kin.21396.

The gas phase reaction of the ground state cyano‐radical (CN (X2∑+)) with 2‐methylfuran (2‐MF) is investigated in a quasi‐static reaction cell at pressures ranging from 2.2 to 7.6 Torr and temperatures ranging from 304 to 440 K. The CN radicals are generated in their ground electronic state by pulsed laser photolysis of gaseous cyanogen iodide (ICN) at 266 nm. Their concentration is monitored as a

The reactions between OH radicals and hydrogen halides (HCl, HBr, HI) have been studied between 298 and 460 K by using a discharge flow‐electron paramagnetic resonance technique. The rate constants were found to be kHCl(298 K) = (7.9 ± 1.3) × 10−13 cm3 molecule−1 s−1 with a weak positive temperature dependence, kHBr (298‐460 K) = (1.04 ± 0.2) × 10−11 cm3 molecule−1 s−1, and kHI(298 K) = (3.0 ± 0.3) × 10−11

The mechanism of the autocatalytic alkoxylation of fatty amines was elucidated using a combined experimental and theoretical approach. The kinetic parameters of the elementary reaction steps are fitted to the experimental data gained in semibatch for propylene and butylene oxides with dodecylamine. A quality‐of‐fit sensitivity study was conducted to assess the robustness and accuracy of the model.

Understanding gas‐phase reactions in model gas mixtures approximating pre‐turbine heavy‐duty natural gas engine exhaust compositions containing NO, NH3, NO2, CH4, CO, and C2H4 is extremely relevant for aftertreatment procedure and catalyst design and is thus addressed in this work. In a plug‐flow reactor at atmospheric pressure, five different model gas mixtures were investigated in the temperature

The rate of reactions in the solid phase with uniform grinding of crystals of dienes, anthracene, and 9,10‐dimethylanthracene, with dienophiles, tetracyanoethylene, N‐phenylmaleimide, and 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione, has been studied. It was shown that, despite the high difference in the reaction rates in solution, the rates of these reactions in the solid phase are much closer. For anthra

Reactive halogen species (ClO and BrO) play a critical role in the stratospheric ozone depletion. However, the reactivity of these radical moieties with volatile organic compounds is also important in determining the composition of the Earth's atmosphere. In this study, the reactions of BrO and ClO radicals with a series of smaller linear alkanes (CnH2n+2, n = 1,2,3, and 4) were studied using the

Selenocysteine (Sec) is a crucial component of mammalian thioredoxin reductase (TrxR) where it serves as a nucleophile for disulfide bond rupture in thioredoxin (Trx). Generation of the reduced state of Sec in TrxR requires consecutive two electron transfer steps, namely: (i) from NADPH to flavin adenine dinucleotide, (ii) from reduced flavin to the disulfide bond Cys59‐S‐S‐Cys64, and finally (iii)

This work reports an investigation on laminar premixed flames of tetralin at 30 Torr and equivalence ratios of 0.7 and 1.7. Measurements of the chemical structure including identification and mole fraction measurements of free radicals, isomers, and polycyclic aromatic hydrocarbons (PAHs) were performed using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV‐PIMS). A kinetic model

The levulinic acid was esterified with alcohol at an alcohol to acid molar ratio of 3:1, 5:1, and 10:1 in the presence of a 0.1 wt% methanesulfonic acid catalyst. During esterification, the temperature was changed linearly from 373 to 428 K and its average change was 4.5 K/min. The authors stated that reactions were of second order and that the activation energy (E) decreased from 61 to 46 kJ/mol in

To understand the effects of the chemical structure of two C5 alkene isomers on their combustion properties, and to highlight the major chemical reactions occurring during their high‐temperature oxidation, water time histories were measured behind reflected shock waves for the oxidation of 1‐pentene (C5H10‐1) and 3‐methyl‐1‐butene (3M1B) in 99.5% Ar. The experiments were carried out at three different