Calculation Of Reaction Rate Constants Research Articles

Controllable Assemblies of Au NPs/P5A for Enhanced Catalytic Reduction of 4-Nitrophenol.

Efficient catalytic reduction of 4-nitrophenol (4-NP) is one focus of industry and practical engineering, because 4-NP is one of the most important sources of pollution of the ecological environment and human health. Here, coassembled hybrid composites of pillar[5]arene (P5A) and gold nanoparticles (Au NPs) were successfully developed by a one-step synthetic method as a type of water-insoluble catalyst for the reduction of 4-NP. The geometric and topological structures, as well as physiochemical properties of Au NPs/P5A composite catalyst, were fully characterized and analyzed through various tests such as transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), indicating that Au NPs were well dispersed on the surface of the two-dimensional film of assembled P5A. The influence factors of the catalytic reduction of 4-NP were further investigated and discussed, confirming that the content of Au NPs and the concentration of 4-NP were very significant during the catalysis. The catalytic reaction was carried out at the catalyst concentration of 100 mg·L-1 and an initial 4-NP concentration of 90 mg·L-1 under 30 °C. The calculated reaction rate constant was 0.3959 min-1 and the reduction rate of 4-NP was more than 95% in 20 min. In addition, the as-prepared catalyst can maintain a high catalytic efficiency after five cycles. Thus, the easily recyclable composite catalyst with poor aqueous solution can exhibit prospective application to the treatment of 4-NP in water.

Automated Skeleton Network Generation for ReaxFF Molecular Dynamics Simulations of Hydrocarbon Fuel Pyrolysis and Oxidation via a Rate-Based Algorithm.

In this study, we present an automated approach of rate-based skeleton network generation for ReaxFF MD simulation (RxMD-SN) for deriving the reaction kinetic mechanism of large hydrocarbon fuels in pyrolysis and oxidation from large-scale ReaxFF MD simulations. The approach contains the statistical calculation of reaction rate constants and the generation of skeleton reaction networks using a rate-based algorithm. The RxMD-SN method takes advantage of reaction flux ranking at a small time interval in terms of temporal reaction rate to extract the core reaction networks, which allows for keeping the rare reaction events that may be dominant in a certain period of the reaction network. The kinetic models derived from ReaxFF MD simulation in CH4 oxidation can reproduce what was obtained in the ReaxFF MD simulation, which demonstrates the capability of RxMD-SN in capturing the global reaction kinetics. An evaluation of reaction rate constants indicates that close kinetic parameters are shared for n-octane oxidation of similar reaction classes, shared oxidation reactions of CH4 against n-heptane, and shared pyrolysis reactions of the RP-3 surrogate fuel against n-heptane. This capability of RxMD-SN is particularly beneficial in meeting the challenges in characterizing the oxidation reaction kinetics of large hydrocarbon molecules. RxMD-SN approach is potentially a general approach in chemical kinetics modeling on the basis of ReaxFF MD simulations.

The reactivity of organic radicals in the performic, peracetic, perpropionic acids-based advanced oxidation process: A case study of sulfamethoxazole

Advanced oxidation processes (AOPs) based on peracetic acid (PAA) displayed great potential in removing emerging contaminants by generating HO• and organic radicals. Performic and perpropionic acids (PFA and PPA) also act as disinfectants, but their application potential has not been investigated yet. Here, we investigated the degradation mechanism and kinetics of sulfamethoxazole (SMX) by HO•, RC(O)O• species (including HC(O)O•, CH3C(O)O• and CH3CH2C(O)O•) and RC(O)OO• species (including HC(O)OO•, CH3C(O)OO• and CH3CH2C(O)OO•). The results show that the calculated reaction rate constants of SMX follow the order of HC(O)O• > CH3C(O)O• > CH3CH2C(O)O• > HO• > HC(O)OO• > CH3C(O)OO• > CH3CH2C(O)OO•. The reactivity towards SMX is strongly correlated with the redox potentials of reactive radicals. Hence, the RCOO• species play dominant roles in the purification of SMX in PFA/PAA/PPA-based AOPs. The degradation of SMX mainly proceeds via addition at the benzene ring, the hydrogen abstraction from the -NH2 group as well as the single electron transfer reaction. This study highlights the fundamental aspects of PFA, PAA, and PPA in the purification of sulfamethoxazole and enhances the role of organic radicals in the AOPs based on organic peracetic acids.

Theoretical study on the kinetics and reaction mechanism involved in the reduction of quinone by 1‐benzyl‐1,4‐dihydronicotinamide

AbstractAlthough it is well known that coenzyme NAD(P)H is involved in anabolic and catabolic reactions in the living organism, there is still significant controversy over the reaction mechanism involved in this biochemical transformation. Thus, 1‐benzyl‐1,4‐dihydronicotinamide was used as a NAD(P)H model in the reduction reaction of 1,4‐benzoquinone (Q), 2,3,5,6‐tetrachloro‐1,4‐benzoquinone, and 2,3‐dicyano‐1,4‐benzoquinone in acetonitrile medium. The kinetic calculations support that formal hydride transfer is the main mechanism promoting Q reduction, while the two‐step process dominates 2,3‐dicyano‐1,4‐benzoquinone reduction. Interestingly, only the single‐electron transfer mechanism takes place when 2,3,5,6‐tetrachloro‐1,4‐benzoquinone is used, affording the corresponding semiquinone derivative as the main product. This mechanistic behavior is related to the presence or absence of electron‐withdrawing groups in the quinones used. Furthermore, the kinetic study results showed that calculated reaction rate constants are in close agreement with experimental results. The results support that formal hydride transfer on the reduction reaction of Q by 1‐benzyl‐1,4‐dihydronicotinamide in acetonitrile proceeds through a hydrogen coupled electron transfer mechanism. This theoretical analysis provides valuable knowledge that can be extrapolated to study the reduction of quinones performed by NADH and NADPH in physiological media.

Theoretical study on hydrogen abstraction reactions from pentane isomers by NO2

The rate constants for the H-abstraction reactions of C5H12 + NO2 are calculated by high-accuracy electronic structure calculations and transition state theory (TST). The investigation includes three pentane isomers, neopentane, n-pentane, and iso-pentane, each of which leads to the formation of three different HONO isomers, namely cis-HONO, trans-HONO, and HNO2. The lowest energy conformers of all relevant species are determined through geometry optimization, frequency analysis, and one-dimensional hindered rotor scanning at the M06-2X/6-311++G(d,p) level of theory, and are further re-optimized using the B2PLYP-D3/cc-pVTZ method. The single point energies of all the reactants, products, and transition states are obtained at the DLPNO-CCSD(T)/CBS level of theory. Traditional transition state theory was employed to derive the rate constants, which were then fitted to obtain the kinetic parameters in the Arrhenius expression. Simulation results show improved performance in ignition delay times and oxidation species prediction, when the calculated reaction rate constants are implemented in the literature n-pentane kinetic models. The results offer enhanced comprehension of the chemistry of C5H12 + NO2, and will aid in the understanding of the mutual reactions of large hydrocarbon fuels and NOx.

Virtual undergraduate chemical engineering labs based on density functional theory calculations

Abstract Offering virtual laboratories to chemical engineering students is likely to extend beyond the COVID-19 era. Thus, there is a need to develop more simulation-based tasks in a wide blend of subjects, spanning thermodynamics, chemical reactions, and unit operations. Molecular and material modeling based on density functional theory (DFT) calculations provides limitless opportunities to train students on how to obtain thermokinetic values that are typically measured experimentally. Through a series of illustrative cases, this contribution provides detailed procedures pertinent to calculating reaction rate constants, standard enthalpies of reactions, redox potentials, equilibrium reaction constants, and surface-assisted mechanisms. We hope that DFT-operated virtual labs will assist students in attaining learning outcomes and promote their self-learning in the above-mentioned subjects. From a broader prospective, the presented case studies are expected to encourage students to appreciate the practical applications of DFT, not only in the academic but also in the industrial domains.

Complementarity and action mechanisms of Fe2+‐activated persulfate and H2O2 system

The Fe2+‐activated persulfate and H2O2 (Fe2+/persulfate/H2O2) system achieved 94% removal of four mixed sulfonamides with 300‐s treatment and possessed excellent complementarity and stability over a wide pH (3–11) and temperature (5–65°C) range. The quenching and electron spin resonance spectroscopy results confirmed the coexistence of sulfate radicals and hydroxyl radicals in the coupled system, which were responsible for the elimination of sulfonamides under ambient conditions. The reaction rate constants of sulfate radicals and hydroxyl radicals at possible reactive sites distinguished the difference in removal ratios of four sulfonamides, according to experimental determination and density functional theory calculations. The removal ratio of sulfathiazole was higher than others because its calculated reaction rate constants of sulfate radicals and hydroxyl radicals were higher than those of sulfamerazine, sulfamethoxazole, and sulfamethazine. The finding provided a reference for investigating the removal mechanism of mixed organic pollutants in the presence of multiple free radicals.

Biodiesel fuel. Part III. Quantum chemical research and simulation of the process

THE PURPOSE. The purpose of this work was to use the associated paradigm for a correct quantum-chemical description of non-catalytic and catalytic supercritical fluid processes of transesterification of triglycerides with alcohols and hydrolysis of triglycerides and to model a one-stage process for obtaining biodiesel fuel, carried out under supercritical fluid conditions with its subsequent scaling to the commercial level.METHODS. The Gaussian09 software product was used to describe quantum chemical studies. The process modeling was carried out using the ASPEN Plus® v2006 software product. The behavior of thermodynamic systems at high temperatures and pressures is modeled using "RK ASPEN EOS". For modeling processes carried out at low pressures, mathematical models UNIQUAC and UNIFAC-LL were used. The scaling of the process was carried out in the VMGSim program.RESULTS. The third part of the review focuses on the quantum-chemical modeling of the transesterification reaction carried out under supercritical fluid conditions. It is shown that taking into account the associative paradigm makes it possible to obtain calculated reaction rate constants that agree in order with the experimental values. And also an analysis was carried out and the results of modeling the process of obtaining biodiesel fuel and scaling it to a commercial level, with a capacity of up to 9000 tons / year, were presented.CONCLUSION. The conducted analysis showed that biodiesel fuel can be a competitive fuel in our and the world market.

Density Functional Theory Study on the Reduction of NO by CO Over Fe3O4 (111) Surface

ABSTRACT Iron or its oxides (FexOy) commonly exist in the ash of fossil fuel and biomass, and are used as oxygen carriers in chemical looping process, and Fe3O4 is a main occurrence. The NO reduction mechanisms by CO over Fe3O4 (111) surface was investigated via density functional theory (DFT) calculations. An optimized unit cell of Fe3O4 was constructed. The interaction between molecules and cell surface was described by the calculated adsorption properties and electronic structures. Results showed that the most stable adsorption of NO/CO belongs to chemisorption and NO has higher adsorption energy than CO. NO can be absorbed onto Fe3O4 surface to form (NO)2 dimer structure, which easily decomposes via a small energy barrier. (NO)2 dimer mechanism is a possible pathway for the reduction of NO by CO over Fe3O4, following three steps: 2NO → (NO)2*, (NO)2* → N2O + O*, O* + CO* → CO2. After the decomposition, the intermediate species N2O molecule and the remaining O atom adsorbed strongly on the Fe3O4 surface can be removed by CO. CO also promotes the gaseous decomposition of N2O. DFT results also showed O2 will prevent NO reduction reaction. The calculated reaction rate constants further verify the existence of (NO)2 dimer mechanism and the rate-limiting step is the removal of the surface O atom.

Degradation of tetramethylammonium hydroxide (TMAH) during UV-LED/H2O2 reaction: Degassing effect, radical contribution, and degradation mechanism

Semiconductor wastewater usually has a low level of dissolved oxygen and alcohol because ultra-pure water used in the process undergoes rigorous degassing and wafer development, respectively. In this study, we investigated the degradation mechanism of tetramethylammonium hydroxide (TMAH), a compound of concern in the semiconductor manufacturing process, during the UV-LED/H2O2 under initial nitrogen purging conditions to remove dissolved oxygen. The effect of the initial degassing was negligible due to the in-situ O2 production during the reaction. Along with hydroxyl radical (•OH), we first observed hydrated electron (eaq•-) formation by electron paramagnetic resonance (EPR) analysis in the presence of an excessive amount of tertiary butanol (t-BuOH), •OH scavenger, during the UV-LED/H2O2 reaction. However, the contribution of eaq•- on TMAH degradation was negligible compared to •OH which played a major role in TMAH degradation. The calculated reaction rate constant of TMAH with •OH was 7.5 × 107 M−1 s−1. From competitive kinetics, [•OH]ss and k•OH, TMAH value was found to be 7.1 × 10−13 M and 7.5 × 107 M−1 s−1, respectively. The optimum pH and temperature for TMAH degradation were pH 7 and 35 °C. Three demethylated amines (trimethylamine, dimethylamine, and methylamine), along with NH4+ and NO3- ions, were detected as the byproducts, implying that the main degradation mechanism of TMAH in this reaction is H abstraction by •OH-induced oxidation and hydrolysis resulting from the •OH-induced oxidation, and demethylation. Our result implies that the UV-LED/H2O2 reaction can be one of the options to treat TMAH contaminated water by recycling H2O2 produced in the semiconductor manufacturing process and lowering the energy consumption by using UV-LED.

Effect of the reactant vibration on quantum dynamics of the reaction H + CH(v = 0,1,2, j = 0) → H2 + C based on a new CH2(X3A″) potential energy surface

Based on the new ab initio potential energy surface of CH2 (X3A″) system, the influence of the reactant vibration on the H + CH → H2 + C reaction has been studied by using quantum time-dependent wave packet method. The results show that for the collision energy lower than 0.47 eV, the vibrational excitation of reactants inhibits the abstraction reaction H + CH → H2 + C, but promotes the exchange reaction H + CH → HC + H. In addition, the vibrational excitation of reactants has also a certain influence on the Coriolis coupling effect. Finally, because of the wider collision energy range (0.010–1.0 eV) in CC and QCT calculations in this work, the calculated reaction rate constants of H + CH(v = 0, j = 0) → H2 + C reaction in the temperature range of 1500–2000 K are much closer to the experimental center value than the existing theoretical results, which shows that the calculation results in this work are more reasonable and accurate.

Novel sulfur vacancies featured MIL-88A(Fe)@CuS rods activated peroxymonosulfate for coumarin degradation: Different reactive oxygen species generation routes under acidic and alkaline pH

A novel rod-shaped MIL-88A(Fe)@CuS featured with sulfur vacancies (SV) were constructed as heterogeneous catalysts for activating peroxymonosulfate (PMS) for coumarin (COU) degradation. A series of xMIL@CuS were obtained according to the mass content of MIL-88A(Fe) in the composites (x, wt% = 50 %, 65 %, and 80 %). Among them, 65 % MIL@CuS hold the best performance, and realized a complete COU removal (30 μM) in 7 min (0.2 g/L 65 %MIL@CuS and 0.5 mM PMS). The degradation was much more favorable in acidic initial pH than alkaline initial pH. The calculated reaction rate constants at initial pH of 3.0, 5.0, 6.0 and 9.0 were 0.903, 0.729, 0.650 and 0.095 min−1, respectively. Electron paramagnetic resonance (EPR) analysis, radical scavenging tests and mechanism exploration indicated that the main difference in degradation under acidic and alkaline pH came from the yield of 1O2. In initial pH = 3.0 condition, SV and lattice oxygen on 65 %MIL@CuS participated in the generation of 1O2, greatly increasing the content of 1O2 (11.6 × 10−11 M) and promoting the degradation. While under initial alkaline condition (pH = 9.0), 1O2 were basically produced from the reaction between Cu(II) and PMS, resulting in a low yield (1.7 × 10−11 M) and lower degradation. Besides, 65 %MIL@CuS maintained excellent reusability with low metal ions leaching, and the degradation exceeded 98.0 % even in the fifth run. Overall, this work provided an efficient and stable activator for activating PMS to degrade refractory organics, and managed to disclose the activation mechanisms under acidic and alkaline pH.

Comparative photo-oxidative degradation of etodolac, febuxostat and imatinib mesylate by UV-C/H2O2 and UV-C/S2O82− processes: Modeling, treatment optimization and biodegradability enhancement

The pharmaceutical contamination in aquatic environment has arisen increasing concern due to its potentially chronic toxicity. In recent years, HO° and SO4°- based advanced oxidation processes (AOPs) have been widely applied in water and wastewater treatments due to their highly efficiency on contaminant removal. Here, the response surface modeling (RSM) was used to investigate the degradation of three typical pharmaceuticals (i.e., etodolac (ETD), febuxostat (FBU) and imatinib mesylate (IMT)) by UV/H2O2 and UV/S2O82− processes. Based on the multiple regression analysis on full factorial design matrix and calculated reaction rate constants, the RSM was built. The experimental rate constants under optimal conditions were quite close to those obtained from the model, implying the good fit of the RSM. In addition, the RSM results indicated that UV/S2O82− process was less sensitive to pH in comparison to the UV/H2O2 process on target contaminant removal. Finally, it showed that UV/S2O82− process was superior to the UV/H2O2 process to on the enhancement of target contaminant biodegradability.

Influence of Vibration–Dissociation Coupling and Number of Reactions in Hypersonic Nonequilibrium Flows

Abstract During the atmospheric cruising of a hypersonic vehicle, the thermal and chemical nonequilibrium effects characterize the flow field within the shock layer. Therefore an understanding of nonequilibrium flow is essential for the efficient design of a hypersonic vehicle. The present numerical study uses various canonical configurations to study the thermochemical nonequilibrium effects in hypersonic flows. The present study investigates the influence of the vibration–dissociation (V–D) coupling method and the number of reactions on shock standoff distance (SSD), vibrational relaxation process, and surface properties. A finite volume method-based solver using the open-source platform openfoam has been developed to analyze the thermochemical nonequilibrium effects in the hypersonic flow field. The current results show that thermal and chemical nonequilibrium flow assumptions significantly affect SSD, and hence these assumptions are necessary to study the cases with a higher degree of nonequilibrium. The number of reactions influences the vibrational relaxation of diatomic gases in the air. At the same time, the V–D coupling method used to calculate reaction rate constants has a negligible impact on the vibrational relaxation process. Moreover, the V–D coupling method and the number of reactions marginally affect surface pressure. However, in the case of surface heat flux, the 11 reaction model predicts higher peak values than the 17 reaction model.

Mild Synthesis of a Dimethoxy‐Terminated Siloxane through a Ring‐Opening Reaction

AbstractAlkoxy‐terminated siloxanes can be used as coupling agents to improve the properties of materials, and they are also widely used in organic synthesis. Herein, a method to synthesize a dimethoxy‐terminated siloxane by the ring‐opening reaction of 2,4,6‐trimethyl‐2,4,6‐trivinyl‐1,3,5,2,4,6‐trioxatrisilinane (D3‐Vi) and methanol under mild condition was reported. The reaction does not require strong acids, strong bases or transition metal catalysts. The structure of the product was confirmed by 1H‐NMR, 29Si‐NMR and mass spectrometry (MS). The Gibbs free energy change of the reaction under the implicit solvent model was calculated by density functional theory (DFT), which proved the feasibility of the reaction. The calculation discussed the two‐step mechanism of the ring‐opening reaction. One methanol attacked D3‐Vi to form a monomethoxy‐terminated product, and then another methanol attacked from the other side to form a dimethoxy‐terminated product. The calculated reaction rate constants of the reaction at different temperatures indicate that the reaction has a tunneling effect, especially at low temperatures. Considering the complex reaction of D3‐Vi and methanol explained why the calculated rate constants at low temperatures were large but the ring‐opening reaction could hardly occur. The mild synthesis can promote the application of alkoxy‐terminated silicones.

Progress towards machine learning reaction rate constants.

Quantum and classical reaction rate constant calculations come at the cost of exploring potential energy surfaces. Due to the "curse of dimensionality", their evaluation quickly becomes unfeasible as the system size grows. Machine learning algorithms can accelerate the calculation of reaction rate constants by predicting them using low cost input features. In this perspective, we briefly introduce supervised machine learning algorithms in the context of reaction rate constant prediction. We discuss existing and recently created kinetic datasets and input feature representations as well as the use and design of machine learning algorithms to predict reaction rate constants or quantities required for their computation. Amongst these, we first describe the use of machine learning to predict activation, reaction, solvation and dissociation energies. We then look at the use of machine learning to predict reactive force field parameters, reaction rate constants as well as to help accelerate the search for minimum energy paths. Lastly, we provide an outlook on areas which have yet to be explored so as to improve and evaluate the use of machine learning algorithms for chemical reaction rate constants.

The Reaction of o-Benzyne with Vinylacetylene: An Unexplored Way to Produce Naphthalene.

The mechanism and kinetics of the reaction of ortho-benzyne with vinylacetylene have been studied by ab initio and density functional CCSD(T)-F12/cc-pVTZ-f12//B3LYP/6-311G(d,p) calculations of the pertinent potential energy surface combined with Rice-Ramsperger-Kassel-Marcus-Master Equation calculations of reaction rate constants at various temperatures and pressures. Under prevailing combustion conditions, the reaction has been shown to predominantly proceed by the biradical acetylenic mechanism initiated by the addition of C4 H4 to one of the C atoms of the triple bond in ortho-benzyne by the acetylenic end, with a significant contribution of the concerted addition mechanism. Following the initial reaction steps, an extra six-membered ring is produced and the rearrangement of H atoms in this new ring leads to the formation of naphthalene, which can further dissociate to 1- or 2-naphthyl radicals. The o-C6 H4 +C4 H4 reaction is highly exothermic, by ∼143 kcal/mol to form naphthalene and by 31-32 kcal mol-1 to produce naphthyl radicals plus H, but features relatively high entrance barriers of 9-11 kcal mol-1 . Although the reaction is rather slow, much slower than the reaction of phenyl radical with vinylacetylene, it forms naphthalene and 1- and 2-naphthyl radicals directly, with their relative yields controlled by the temperature and pressure, and thus represents a viable source of the naphthalene core under conditions where ortho-benzyne and vinylacetylene are available.

Photodegradation and ozonation of ibuprofen derivatives in the water environment: Kinetics approach and assessment of mineralization and biodegradability

This article presents the results of studies on the degradation of ibuprofen transformation products: 1-hydroxyibuprofen (1OHIBF), 4-ethylbenzaldehyde (4EBA), 1-[4-(2-methylpropyl)phenyl]ethan-1-ol (MPPE) in water. To the best of our knowledge, this is the first paper where the ozonation and photodegradation (VIS and UV photolysis, degradation in H2O2/UV system, photosensitized oxidation) of 1OHIBF, 4EBA and MPPE are reported. The processes were performed in demineralized and natural river water. The influence of various reaction parameters on the removal degree was checked. Both, photolysis under VIS light and photosensitized oxidation of target compounds are very low-efficient processes. Ozonation and degradation in H2O2/UV system are effective methods for ibuprofen derivatives degradation. Components present in river water reduced removal degree of investigated compounds during ozonation and degradation in H2O2/UV system. The biodegradability assessment using the Average Oxidation State (AOS) and COD/TOC ratio proved the formation of more oxidized by-products during both processes. The determined second-order rate constants for ozone reaction with 1OHIBF, 4EBA and MPPE are 0.1 ± 0.01, 10.95 ± 1.36 and 3.04 ± 0.33 M−1 s−1, respectively. The calculated reaction rate constants of hydroxyl radicals with MPPE, 4EBA and 1OHIBF are 3.57 × 109, 6.83 × 109 and 1.06 × 109 M−1 s−1, respectively.

Calculation of reaction rate constants from a classical Wigner model based on a Feynman path integral open polymer

The Open Polymer Classical Wigner (OPCW) method [J. Chem. Phys. 152, 094111 (2020)] is applied to a flux-Heaviside trace for calculating reaction rate constants. The obtained expression for the reaction rate constant is tested on a symmetric Eckart potential. The OPCW method is shown to converge toward the exact classical Wigner result. The OPCW method shows some promise for rate constant calculations and suggestions for future tests are made.

Study of selective hydrogenation of biodiesel in a DBD plasma reactor

In order to achieve the selective hydrogenation of biodiesel at room temperature and under normal pressure, we researched the upgrading of soybean biodiesel using a dielectric-barrier discharge (DBD) reaction system. Using Raney-Ni as the hydrogenation catalyst, the effects of the operating parameters on the hydrogenation depth and the selectivity of biodiesel were systematically analyzed. The results show that the polyunsaturated components in soybean methyl ester were reduced by 57.04%, and that the polyunsaturated components were hydrogenated to monounsaturated components with a selectivity of 77.75%. Based on the gas chromatography and mass spectrometry (GC-MS) test results, we established a kinetic model for biodiesel hydrogenation. A comparison of the calculated and experimental results shows that the hydrogenation of the biodiesel can be described by a quasi first-order reaction model. The calculated reaction rate constants indicate that under DBD plasma reaction conditions, the hydrogenation of biodiesel has high selectivity for the formation of monounsaturated components.