Eyring Equation Research Articles

Kinetic study for styrene carbonate synthesis via CO2 cycloaddition to styrene oxide using silica-supported pyrrolidinopyridinium iodide catalyst

Reaction kinetics for heterogeneous catalysis of styrene carbonate (SC) synthesis via CO2 cycloaddition to styrene oxide (SO) using silica-supported pyrrolidinopyridinium iodide (SiO2-PPI) catalyst has been investigated. The results obtained from the mixing study and theoretical analysis based on Thiele modulus (< 0.4) and effectiveness factor (∼1.0) revealed no external and internal mass transfer limitations. The experimental results were compared with pseudo-homogeneous (PH) and Langmuir-Hinshelwood (LH), Eley-Rideal (ER) heterogeneous kinetic model. The experimental data was found to be the best fit with the ER model among the three kinetic models. Moreover, the Arrhenius and Eyring equations were used to determining the activation energy (i.e. 64.9 kJ mol–1) and thermodynamic activation parameters such as enthalpy of activation (ΔH‡= 60.6 kJ mol–1), the entropy of activation (ΔS‡ = –148.3 J mol–1 K–1) and Gibb’s free energy (ΔG‡ = 115.9 kJ mol–1 at 373 K). The SiO2-PPI heterogeneous catalyst exhibited excellent reusability: up to five cycles without any substantial decrease in activity and selectivity towards SC formation.

Kinetic compensation effect of isoconversional methods

For experimental data obtained under different reaction/process conditions over time or temperature, the kinetic compensation effect (KCE) can be expected. Under dynamic (nonisothermal) conditions, at least two analytical pathways forming the KCE were found. Constant heating rate (q = const) and variable conversion degrees (α = var) lead to a vertical source of the KCE, called the isochronal effect. In turn, for a variable heating rate (q = var) and constant conversion degree (α = const), we can obtain an isoconversional compensation effect. In isothermal conditions (analyzed as polyisothermal), the KCE appears only as an isoconversional source of the compensating effect. The scattering of values for the determined isokinetic temperatures is evidence of a strong influence of the experimental conditions and the calculation methodology. The parameters of the Arrhenius law have been shown to allow the determination of the KCE and further the isokinetic temperature. In turn, using the Eyring equations for the same parameters, we can determine the enthalpy–entropy compensation (EEC) for the activation process and the compensation temperature, which is often treated as an isokinetic temperature. KCE effects have also been shown to be able to be amplified or dissipated, but isokinetic temperature is not a compensating quantity in the literal sense in isoconversional methods because {T}_{iso}to infty . Thus, in isoconversional methods, isoconversional KCE values are characterized by strong variability of activation energy corresponding to the weak variation of the pre-exponential factor, which in practice means that {text{ln}}mathit {A}to {text{const}}. This is completely in line with the classical Arrhenius law.

Mn(III) active site in hydrotalcite efficiently catalyzes the oxidation of alkylarenes with molecular oxygen

Developing efficient heterogeneous catalytic systems based on easily available materials and molecular oxygen for the selective oxidation of alkylarenes is highly desirable. In the present research, NiMn hydrotalcite (Ni2Mn-LDH) has been found as an efficient catalyst in the oxidation of alkylarenes using molecular oxygen as the sole oxidant without any additive. Impressive catalytic performance, excellent stability and recyclability, broad applicable scope and practical potential for the catalytic system have been observed. Mn3+ species was proposed to be the efficient active site, and Ni2+ played an important role in stabilizing the Mn3+ species in the hydrotalcite structure. The kinetic study showed that the aerobic oxidation of diphenylmethane is a first-order reaction over Ni2Mn-LDH with the activation energy (Ea) and pre-exponential factor (A0) being 85.7 kJ mol−1 and 1.8 × 109 min−1, respectively. The Gibbs free energy (ΔG≠) was determined to be -10.4 kJ mol-1 K-1 for the oxidation based on Eyring-Polanyi equation, indicating the reaction is exergonic. The mechanism study indicated that the reaction proceeded through both radical and carbocation intermediates. The two species were then trapped by molecular oxygen and H2O or hydroxyl species, respectively, to yield the corresponding products. The present research might provide information for constructing highly efficient and stable active site for the catalytic aerobic oxidation based on available and economic material.

Non-conservation of activation energy barriers in the same chemical process: a cooperative (effect) proton transfer on (HF)n molecular aggregates

The formation of (HF)n aggregates with n = 2, 3, 4, 5 and 6 and concerted proton transfer processes in these aggregates were systematically analyzed. It was verified that, by a cooperative effect, the barrier associated with the proton transfer process decreases for aggregates with a larger number of molecules, indicating that the activation energy for proton transfer depends on the molecularity of the process. Natural bond orbital and quantum theory of atoms in molecules were used to characterize the strength of the hydrogen bonds established in the aggregates, which verified a general increase in the delocalization energy as a function of increasing aggregate size. A deformed Eyring (d-Eyring) equation was used to calculate the proton transfer rate constants, where the d-Eyring equation adequately described the proton transfer kinetics. Analysis of the rate constants showed that proton transfer became faster as the cluster size increased. Arrhenius and d-Arrhenius plots showed a decrease in the dependence of the rate constants on temperature, particularly for the tetramer, pentamer, and hexamer. The d-Arrhenius plots, for which the d parameter was included in the Eyring equation, suggest non-Arrhenius behavior for proton transfer in the HF aggregates at low temperatures.

Arrhenius Equation Modeling for the Oxidative Stability Evaluation of Echium Oil Enriched with a Natural Preservative

AbstractThe present study evaluates the oxidative stability of refined echium oil supplemented with Sophora japonica L. extract (200 ppm). Commonly used synthetic antioxidants (butylated hydroxytoluen (BHT), ascorbyl palmitate, and quercetin) are used as reference additives. The plant extract is evaluated to possess better in vitro antioxidant potential than BHT, and comparable to that of quercetin. The degradation kinetics at 6, 25, and 60 °C with and without antioxidants is studied, as well as the progress of oil oxidation. The temperature dependence of oxidation is expressed with the Arrhenius equation in addition to reaction rate constant (k) and activation energy (Ea) also determined using Arrhenius equation. Enthalpy of activation (ΔH‡), entropy of activation (ΔS‡), and Gibb's free energy of activation (ΔG‡) are calculated according to the Eyring equation. It is established that the rate constant increased with the temperature of storage. The lipid oxidation reactions are established to follow a zero‐order kinetic model for peroxide value. The oxidation reaction is determined as exothermic and non‐spontaneous. In conclusion, S. japonica extract is evaluated with high antioxidant potential and can be used as a promising oil stabilizer. It can successfully be added to prevent lipid structure oxidation while providing health benefits to consumers.Practical Applications: The application of natural antioxidants in edible oils in order to substitute synthetic additives is a matter of research interest. The present study aims to compare commonly used synthetic antioxidants with natural ones. Ascorbyl palmitate has the greatest ability to stabilize echium oil at 6, 25, and 60 °C, but the Sophora japonica L. extract possesses good potential for retarding the oxidation. The results of this study outline the potential of the natural extract of S. japonica, which needs to be further studied.

Sol-gel-derived 58S bioactive glass containing holmium aiming brachytherapy applications: A dissolution, bioactivity, and cytotoxicity study

Bioactive glasses containing rare earth elements have been proposed as promising candidates for applications in brachytherapy of bone cancer. However, their safety relies on a proper dissolution to avoid radioactive materials in the human body, and desirable bioactive properties to regenerate the bone defect caused by the tumor. In this work, we proposed a new series of sol-gel-derived bioactive glasses containing holmium oxide, based on the system (100-x)(58SiO2-33CaO-9P2O5)-xHo2O3 (x = 1.25, 2.5 and 5 wt%). The glasses were characterized regarding their dissolution behavior, bioactivity, and cytotoxicity with pre-osteoblastic cells. Also, in the dissolution experiments, the Arrhenius and Eyring equations were used to obtain some thermodynamic properties of glass dissolution. The results evidenced that the addition of holmium ions in the glass structure decreased the energy barrier of hydrolysis reactions, which favors glass dissolution in an early-stage. However, in the long-term, the strength of Si-O-Ho bonds may be the cause of more stable dissolution. Besides, glasses containing holmium were as bioactive as the 58S bioactive glasses, a highly bioactive composition. Cytotoxicity results showed that all glasses were not cytotoxic, and the composition containing 5 wt.% of Ho2O3 enhanced cell viability. Finally, these results suggest that these glasses are suitable materials for brachytherapy applications due to their proper dissolution behavior, high bioactivity, and high cell viability.

Influence of Cholesterol Concentration on Bacteriorhodopsin Photocycle

The photocycle of the membrane protein bacteriorhodopsin in Dipalmitoylphosphatidylcholine(DPPC)/Cholesterol membranes with various cholesterol concentrations has been studied using the time-resolved spectroscopy method. The temperature dependences of the rate constants of bacteriorhodopsin transitions between transient states are shown to satisfy the Eyring equation. It is proved that the growth of the cholesterol concentration in the DPPC membrane accelerates the bacteriorhodopsin photocycle.

Theoretically consistent calculation of viscous activation parameters through the Eyring equation and their interpretation

The activation parameters of viscous flow can be used to probe the molecular interactions in fluids from viscosity experimental data. They are assessed by mathematical derivations of the Eyring equation, but differences in these derivations can generate parameters that lead to conflicting interpretations. In this work, a new method for the estimation of the activation parameters of viscous flow is proposed and compared with two other methods previously reported in the literature. It is shown that the new method is the only presenting theoretically consistent trends, as confirmed by its application to alkanes and ionic liquids.

Decolorization of Textile Dye by Halophilic Exiguobacterium sp.VK1: Biomass and Exopolysaccharide (EPS) Enhancement for Bioremediation of Malachite Green

AbstractThe salt pan soil screened for the exopolysaccharides (EPS) producing organisms for the decolourization textile dyes. The isolate was characterized and confirmed as Exiguobacterium sp. VK1 by 16S rRNA analysis. The enhanced production of EPS was obtained with the minimal medium which was supplemented with various carbon sources, and cassava peel which has shown a 5.9 fold increase in the EPS (7704.71 mg/L) production. Exiguobacterium sp. VK1 removed Malachite Green (MG) dye (684.38 mg/g) with the maximum biosorption capacity of 79.1% at pH 6 and 40°C. With the increased EPS production, by supplementing the cassava peel, the MG dye adsorption also increased up to 97.61%, when decolorized within 30 min by Exiguobacterium sp. VK1. It was found that Pseudo Second‐order kinetics and Freundlich isotherm is the best fit for the equilibrium adsorption process of MG dye by Exiguobacterium sp. VK1. The thermodynamic properties such as activation energy (12.993 kJ/mol), change in enthalpy (10.501 kJ/mol), change in entropy ‐254.07 J/(mol K) and change in Gibbs energy (84.945‐90.026 kJ/mol) were investigated by Arrhenius and Eyring equation using Pseudo‐second‐order kinetic model. The result revealed that the adsorption process was thermodynamically feasible.

Temperature dependence of elastic constants in unidirectional carbon fiber reinforced shape memory polymer composites

The work describes a model to predict the elastic constants of unidirectional carbon fiber reinforced shape memory polymer composites (SMPCs) with different fiber volume fractions within the temperature range of 293 K to 393 K. The model is based on a theoretical description of the phase transition of the shape memory polymer (SMP). Two glassy phase volume fraction functions are developed, one based on the Eyring equation, the other based on the normal distribution equation. The longitudinal and transverse moduli, axial and transverse shear moduli, and axial Poisson's ratio are derived by using the glassy phase volume fraction function and modified rule of mixture. The axial Poisson's ratio increases with the temperature increase, while the other four constants decrease nonlinearly with rising temperatures. An inverse identification of the elastic constants at different temperature via numerical and experimental modal analysis from a flat SMPC laminate shows that the model proposed is adequate to describe the temperature dependence of the elastic constants of the laminate.

Kinetics and thermodynamics of synthesis of palm oil-based trimethylolpropane triester using microwave irradiation

Enhancement of reaction performance utilizing microwave irradiation has drawn so much interest due to its shorter reaction time and low catalyst loading. These advantages are particularly significant from kinetics and thermodynamics perspectives. This study aimed to investigate the kinetics and thermodynamics of microwave-assisted transesterification of palm oil-based methyl ester into biolubricant. The transesterification reaction of palm oil methyl ester (PME) and trimethylolpropane (TMP) was conducted at 110–130 °C for 90 min under vacuum condition. Sodium methoxide was employed as the catalyst at 0.6 wt% of reactants fixed at molar ratio of 4:1 (PME: TMP). The experimental data were fitted with the second-order reversible reaction kinetics mechanisms. The data were solved via Runge-Kutta 4,5 order using MATLAB software. Analysis on the data revealed that the reaction rate constants at temperatures of 110–140 ℃ were in the range of 0.01–0.63 [(w/w)(min)]−1, with standard errors of 0.0026–0.0228 within 99.99% prediction interval. Microwave-assisted reaction obtained 17.0 kcal/mol of activation energy. This method reduced activation energy by 49% as compared to the conventional heating. Activation energy and time-periodic energy assessment showed that the reaction was endothermic. The reaction at 130 °C is the easiest to activate. The positive Gibbs free energy (ΔG > 0) found using Eyring-Polanyi equation indicated that the transesterification was non-spontaneous and endergonic.

Microwave-Enhanced Chemistry at Solid-Liquid Interfaces: Synthesis of All-Inorganic CsPbX3 Nanocrystals and Unveiling the Anion-Induced Evolution of Structural and Optical Properties.

We demonstrate how microwaves could enhance the chemistry at interfaces of heterogeneous reactions involved in the microwave-solvothermal (MW-ST) synthesis of all-inorganic CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (PNCs) within 6 min, unlike a conventional hot-injection method that requires 3 h. The enhanced MW-ST reaction rate was quantitatively analyzed by the Eyring equation, and it has been observed that the decreased activation free energy (ΔG⧧) and increased activation entropy (ΔS⧧) are caused by changes in the relative energies of reactants at their solid-liquid interfaces, leading to the formation of "hot spots", where microwave energy absorption is at its maximum. This rapid and homogeneous microwave heating could facilitate the self-assembly of uniformly distributed CsPbX3 nanocubes with precise control over the stoichiometric ratio, as confirmed by high-resolution transmission electron microscopy and energy-dispersive X-ray analyses. X-ray diffraction and Raman results indicate that lattice contraction and expansion in CsPbBr3-yXy have occurred because of an increase in the metal-halide bond length upon moving down the groups Cl → Br → I, as further ascertained by the Rietveld refinement studies. These anion-induced structural variations accordingly affected the electronic properties of MW-ST-synthesized CsPbX3 PNCs, which is apparent from the shifts in their conduction-band (CB) and valence-band (VB) positions. Consequently, the optical properties were also altered, resulting in a color-tuned emission from blue to red, with excellent photoluminescence quantum yields (up to 92%) and narrow emission line widths, as is evident from UV-vis and photoluminescence spectroscopy. The MW-ST-synthesized CsPbX3 PNCs were used as color-conversion layers for the fabrication of light-emitting diodes (LEDs) with commercial 456 nm UV-LED chips.

Study of Molecular Interaction for Antibiotic Drug with Sugar Solutions at Different Temperature

The interactions of drug amoxicillin with maltose or galactose solutions with a variation of temperature have been discussed by taking in the volumetric and viscometric procedures. Physical properties [densities (ρ) and viscosities (η)] of amoxicillin (AMOX) aqueous solutions and aqueous solutions of two type saccharides (maltose and galactose 0.05m) have been measured at T = (298.15, 303.15 and 308.15) K under atmospheric pressure. The apparent molar volume (ϕv cm3mole-1) has been evaluated from density data and fitted to a Redlich-Mayer equation. The empirical parameters of the Mayer-Redlich equation and apparent molar volume at infinite dilution Ø°v were explicated in terms of interactions from type solute-solvent and solute–solute interactions. Transfer molar volume ΔtraØ°v for AMOX from water to aqueous maltose and galactose solutions were calculated to comprehend different interactions in the ternary solutions. Limiting apparent molar expansibility (Ø°E) and Hepler’s coefficient was also calculated to indicate the structure making ability of AMOX in the ternary solutions. Jones–Dole coefficient B and A have been calculated from viscosity data by employing the Jones–Dole equation. The free energy of activation of viscous flow per mole of the solute (Δμ°2*) and solvent (Δμ°1*) have been explained on the basis of the Eyring and Feakins equation.

Accumulation mechanism of tetracycline hydrochloride from aqueous solutions by nylon microplastics

Abstract Nylon microplastics and tetracycline hydrochloride (TH) coexist ubiquitously in the coastal aquaculture areas. In this study, the nylon microplastics were characterized by the scanning electron microscope (SEM) and Fourier transform-infrared spectroscopy (FTIR). Kinetic experiments were performed at various microplastics size and reaction temperature, respectively. The effects of adsorbate concentration, initial solution pH, ionic strength and Pb 2 + ions concentration were investigated. Desorption experiments were quantified in aqueous solutions and under simulated gut conditions, respectively. The results show that the sorption kinetics of TH onto nylon microplastics closely conform to both the pseudo-second-order model and the intraparticle diffusion model. The fitting sorption isotherm models (Linear, Freundlich and Langmuir) of TH onto nylon microplastics were highly linear. In addition, the activation energy ( E a ), activation enthalpy ( Δ H # ), activation entropy ( Δ S # ) and free energy ( Δ G # ) of the sorption process were obtained by the Arrhenius and Eyring equations, indicating the TH sorption process was spontaneous and exothermic in nature. TH uptake by nylon microplastics was essentially independent on ionic strength, the presence of Pb 2 + ions was found to inhibit TH sorption and TH uptake is highly dependent upon solution pH. These results suggest that the sorption of TH by nylon microplastics is predominated by Van der Waals forces and the migration of nylon microplastics after TH sorption in the presence of metal ions requires further research attention.

Influence of TTAB/14-S-14 Micelles on the Rate of the Condensation between Ninhydrin and Mercury-Dipeptide Complex in Absence and Presence of Salts and Organic Solvents: A Kinetic Approach

The interaction of mercury(II)–glycyl-L-alanine [Hg(II)–Gly-L-Ala]+ complex with ninhydrin has been studied kinetically both in aqueous as well as micellar media (cationic conventional/gemini surfactants) using UV-vis spectrophotometer at 70 ºC and a particular pH 5.0. The study was carried out as functions of [Hg(II)–Gly-L-Ala]+, [ninhydrin], [surfactant] [salts], and solvents (%v/v). The first-order-rate is observed concerning [Hg(II)–Gly-L-Ala]+, whereas fractional-order-rate dependence for [ninhydrin]. It has been found that 14-s-14 geminis enhance the rate of reaction more effectively than related cationic conventional surfactant tetradecyltrimethylammonium bromide (TTAB). The effect of additives such as salts (inorganic/organic) and organic solvents on the rate was also investigated. The reaction rate was explained in terms of the modified pseudo phase model (considering the association/adsorption of both the reactants on the micellar surface) and changes in micellar morphology occurring at higher [geminis]. The Eyring equation is valid for the reaction over the range of temperatures used. Various thermodynamic parameters and binding constants between reactants with the micelles have been evaluated.

P-aminophenol catalysed production on supported nano-magnetite particles in fixed-bed reactor: Kinetic modelling and scale-up

The aim of this work was to investigate on the possibility to use nano-magnetite particles supported on waste biomass as heterogeneous catalyst for the production of p-aminophenol starting from a well-known pollutant, p-nitrophenol, in fixed-bed reactors. The kinetic and the thermodynamic of the process was firstly studied in batch system, subsequently a first scale-up was performed using a glass column packed with the supported catalyst. The experimental data obtained with the column were interpreted in light of a suitable dynamic model. The Langmuir-Hinshelwood mechanism well described the process, obtaining from the data fitting a surface rate kinetic constant k = 2.68 × 10−6 mol/m2·h, an adsorption equilibrium constants for PNP and BH4− species equal to 20.07 l/mol and 1.83 l/mol, at 25 °C. The Eyring equation was used to fit the apparent kintic constant variation with the temperature, to estimate thermodynamic parameters, obtaining a ΔH = −1145.68 kJ/mol and ΔS = −315.02 kJ/K·mol. The process was then simulated in PROII environment, investigating the influence of initial PNP flowrate, NaBH4/PNP and reactor length/diameter ratios on PNP conversion, on required duty to maintain isothermal conditions and on pressure drops in the reactor.

Synthesis and characterization of physicochemical properties of new ether-functionalized amino acid ionic liquids

Abstract Since the effect of ether functionalities on physicochemical properties varies strongly, So the experimental study of in properties is still primarily important for ether-functionalized ionic liquids to be properly applied, as well as for providing reference data for more reliable predictions. In this work, two novel ether-functionalized amino acid ionic liquids 1-(2-methoxyethyl)-3-methylimidazolium threonine and 1-(2-ethoxyethyl)-3-methylimidazolium threonine were synthesized and characterized. Physicochemical properties, including density, surface tension, viscosity and refractive index were measured at different temperatures and atmospheric pressure. According to the volumetric properties of ether-functionalized ionic liquids, the contribution of an ether O atom in the alkoxy side chain to molecular volume, standard entropy and lattice energy were estimated to be 0.0102 nm3, 13 J·K−1·mol−1 and 3 kJ·mol−1, respectively. Combined the molar surface Gibbs energy with Lorentz-Lorenz relationship, an equation for predicting surface tensions of ionic liquids was obtained, and the predicted values agree well with the experimental data. Moreover, an equation of the polarity coefficient P was proposed and the polarity of other ionic liquids was estimated. The polarity of the same series of ionic liquids decreases with the length of the alkoxy chain, the hydrophilicity becomes relatively weak, and the hydrophobicity is relatively enhanced. Using Eyring's viscosity equation and thermodynamic formula, an expression for calculating the viscous flow activation energy of ionic liquids was obtained, and the values were in good agreement with the values calculated by the Arrhenius equation.

Screening of the best formula for flame type high energy burner

In order to explore the best formula of flame-type high-energy burner, this paper selects 7 groups of flame-type high-energy burners with good stability, high energy and a wide range of raw materials based on the existing literature and patents. The Gibbs free energy Values of 7 groups of formulations at different temperatures were calculated by using the chemical thermodynamic formula, and the changes in Gibbs free energy Values of 7 groups of formulations were drawn, which provided a basis for the calculation of reaction rate k value by Eyring equation. Then, according to the calculation theory of chemical reaction calorific value, the heat of reaction of 7 different formulations at different temperatures was calculated. The results show that the Gibbs free energy value of Al/MnO2 in the seven groups of formulations is much smaller than that of the other groups in the same reaction temperature environment, and decreases with increasing temperature. According to the Arrhenius formula and the Eyring equation, the reaction rate of Al/MnO2 is the fastest in each group. When the other conditions are constant, the reaction enthalpy of Al/MnO2 is the smallest in each group, therefor the heat released by the reaction is the most. In summary, under the same quality conditions, the Al/MnO2 flame type high energy burner formulation has the fastest reaction rate and the most heat release, which provides theoretical guidance for experimental design and practice.

Catalytic influence of 16-s-16 gemini surfactants on the rate constant of histidine and ninhydrin.

The present paper reports the catalytic influence of 16-s-16 (spacer (s) = 4, 5, 6) gemini surfactants on the rate constant of histidine and ninhydrin at 343 K and pH 5.0 using the spectrophotometric technique. The effect of varying amounts of geminis was made on the rate constant of histidine and ninhydrin keeping other constituents constant. Characteristics of the rate constant (kψ) versus [gemini] depict the effect of surfactants on the rate constant. A systematic explanation about the effect of surfactants is revealed and discussed in the text. The influence of different parameters that includes [reactants], temperature and pH has also been performed on the study. In order to determine the critical micelle concentration (cmc) of pure surfactants and their solution mixtures, conductivity measurement was employed. By using the Eyring equation, activation parameters at different temperatures have been obtained. The resultant data of kψ versus [gemini] plot were rationalized with the pseudo-phase model of micelles.

Analysis of Thermochemical Properties of three typical Manganese based thermite

In order to investigate the thermochemical and reactive properties of thermite composed of typical manganese oxides, three common manganese oxides meaning MnO2, Mn2O3 and Mn3O4, are selected in this paper to form aluminothermic agent with Al powder, respectively. According to the chemical thermodynamics, the difference of Gibbs free energy among different components is calculated, and the reaction rate k is calculated according to Eyring equation, then the Gibbs free energy values of three thermite at different ambient temperatures are drawn. Furthermore, according to the theory of chemical reaction calorific value calculation, the reaction calorific values of three thermite at different temperatures are calculated. The results show that the Gibbs free energy of Al/MnO2 system is the smallest at different temperatures, the reaction rate and the enthalpy of reaction of Al/MnO2 are the fastest and the smallest at different temperatures and the heat release is the largest. The results of calculation provide theoretical guidance for experimental design and practice. Under the condition of the same mass of reactants, the discharge heat of MnO2 is the largest, and the heat value of the MnO2 is the highest.