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The MgO–Al2O3–SiO2–TiO2 glass system was prepared by melting method. The crystallization behavior and crystallization kinetics of a sample with glass ceramic composition were examined. DTA and XRD analyses revealed the crystallization of Ca0.965Mg2Al16O27 cordierite (Mg2Al4Si5O18) and Fe2TiO5 phases. The activation energy for the crystallization of...
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... here to download Manuscript: Manuscript. docx 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64strengths of up to 250 MPa above 1200°C temperature of heat treatment [5]. The properties of glass-ceramics depend on their microstructure, and the microstructure primarily depends on the melting matrix structure prior to solidification, and the cooling rate, which is related to the presence of crystal defects, the melting matrix structure prior to solidification and the method of the phase transformation dynamics. ...
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... waste was supplied from KUMAŞ Company, Turkey and, Kaoline, Quartz and Alumina were supplied from Celvit Company, Turkey. The chemical compositions of raw materials are given in Table 1. The powders of technical grade TiO2 (>99.5%) were used present study. ...
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... Quartz, 35% Magnezite Waste, 25% Kaolinite 20% Alumina and excess 8% TiO2 were mixed corresponding to stochiometric according to chemical formula cordierite (2MgO·2Al2O3·5SiO2) in asshless rubber-lined ceramic jars for 2 h using zirconia balls and distilled water as the milling media and then drying at 110 °C for 24 hour. 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64The homogeneous mixture was melted in an alumina crucible at 1500 o C for 2 h using a Heraeus electric furnace. ...
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... Song et al. [17] investigated the crystallization mechanism of low temperature cordierite (K2O-MgO-Al2O3-SiO2) glass ceramics and they showed that cordierite phase formed at 900 o C. Dittmer et al. [18] investigated phase evolution in MgO-Al2O3-SiO2 with ZrO2 as nucleating agent and they reported that after annealing the sample at 1200 •C, the main crystalline phase is cordierite or cristobalite. 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 SEM micrographs analysis of glass and glass ceramics samples are given in Fig. 4(a-e). The SEM microstructure of the annealed glass sample exhibits a classical amorphous structure; the materials had homogeneous and smooth surface (Fig. 4a). ...
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... two most important kinetics parameters, the activation energy (Ea) of the crystallization and Avrami parameter (n), were obtained from the relationship between heating rate () and temperature of crystallization (Tp) in the exothermic peaks DSC or DTA curve using Kissinger [13] í µí±£í µí± . 1 í µí± í µí± ⁄ are given in Fig. 7(a,b). And from the value of the crystallization activation energy (Ea), the Avrami parameter (n) was calculated by Augis-Bennet 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64where, T is the full width of the exothermic peak at the half maximum intensity and Tp is the crystallization peak temperature (Table 2). Consequently, a sharp peak (small T, large n) implies bulk characterization, whereas a broad peak (large T, small n) signifies surface crystallization [21]. ...
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... Avrami parameter "n" range from 3,43-3,98. This value indicates that the dominant crystallization mechanism for this system is bulk crystallization dominated by three-dimensional growth . 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 ...
Citations
... The second is binary compounds, which include clays, talc, and sepiolite; the third is ternary compounds, which include chlorite. Industrial wastes such as magnesite and glass slag are also used in cordierite production [4,5]. ...
The corrosion degrees of produced non-activated and activated cordierite-based ceramics were investigated in hydrochloric and sulfuric acid solutions. The composition of talc, alumina, and kaolinite powders was mechanically activated in a planetary mill. The concentrations of aluminum, magnesium, silicon, calcium, and potassium leached to the acid solutions from non-activated and activated cordierites were measured using ICP-OES. The amorphization of the structures was examined by XRD analysis. As a result, it has been determined that activated cordierite-based ceramics are more durable, and sulfuric acid solution causes more corrosion than hydrochloric acid.
... La fase cristalina cordierita, es obtenida a partir del control de agentes nucleantes y de tratamientos térmicos que influencian las fases cristalinas formadas. (Başaran et al., 2016). Las ventajas de este material vitrocerámico en la construcción es que presenta mejores propiedades mecánicas y de resistencia a la abrasión que el gres porcelánico y que puede ser moldeado en caliente en función de su lugar de colocación, debido a la existencia de un alto porcentaje de vidrio residual. ...
... Desde el punto de vista ambiental, la obtención de vitrocerámicas es ideal para reutilizar residuos inorgánicos incluyendo los de carácter tóxicos como es el caso de la escoria de alto horno enfriada en aire, o por sus siglas en ingles GBFS (Başaran et al., 2016) (Rondón et al., 2018). ...
Resumen Actualmente, la tendencia mundial está orientada a cerrar los ciclos productivos, con el fin de minimizar el volumen de residuos que van a parar a depósitos y vertederos y con ello disminuir el impacto ambiental en todos los ámbitos. El uso de subproductos industriales en el sector productivo es una alternativa ecológica que promueve la reducción de emisiones de dióxido de carbono a la atmósfera, debido a un menor consumo de materias primas de origen natural para la fabricación de diferentes materiales. Entre los diferentes residuos generados en los procesos productivos, está la escoria siderúrgica de alto horno (GBFS). Este residuo generado durante la manufactura de acero ha venido siendo aprovechado en los últimos años para la producción de diversos tipos de materiales, entre ellos los materiales de construcción. Entre sus diferentes usos se destaca su empleo en la fabricación de cementos, concretos, tejas, ladrillos, estabilización de suelos, vitrocerámicas, entre otros. Esta revisión se realizó con artículos desde el año 2010 hasta enero de 2021, con el fin de generar un documento donde se puedan identificar claramente las principales características y propiedades de los materiales producidos con GBFS e incorporaciones pequeñas de residuo de cenizas de carbón. Se encontró que el uso de GBFS y cenizas ofrecieron los componentes químicos necesarios como CaO, SiO2 y Al2O3 para permitir la aparición de las fases cristalinas necesarias para el desarrollo apropiado de las propiedades típicas en los materiales cerámicos producidos. Palabras clave: residuos industriales; escoria siderúrgica; vitrocerámicas; cemento; suelos. Abstract Currently, the global trend is aimed to closing production cycles, in order to minimize the volume of waste that goes to deposits and landfills and thereby reduce the environmental impact in all areas. The implementation of industrial by-products in the manufacturing sector is an ecological alternative which promotes the reduction of carbon dioxide emissions to the 2 atmosphere, due to a low consumption of natural raw materials for the manufacture of different materials. Among the different wastes generated in production processes the ground granulated blast furnace slag (GBFS) is one of the most used. This waste is generated during the manufacture of steel has been used in recent years for the production of various types of materials, including ceramics. It has different uses including its utilization in the manufacture of cements, concretes, tiles, bricks, soil stabilization, glass-ceramics, among others. This review was carried out with articles from 2010 to January 2021, in order to generate a document where the main characteristics and properties of ceramic materials produced with GBFS and small incorporations of fly ash waste can be clearly identified. It was found that the use of GBFS and fly ash offered the necessary chemical components such as CaO, SiO2 and Al2O3 to allow the formation of the crystalline phases necessary for the adequate development of the typical properties of the ceramic materials produced.
... Meanwhile, an increase in the MgO content, as the glass network modifier, can destroy the Si-O bond and break the oxygen bridges, thereby worsening the glass structure and reducing the viscosity of the glass melt to promote glass crystallisation [39]. The influence of main glass compositions on the crystallisation kinetics of the MAS glass samples was investigated using the Kissinger equation and Augis-Bennett equation [40][41][42][43][44], which are expressed as follows: ...
... It can be inferred that n = 1, 2, 3 and 4 can approximately represent surface crystallisation, two-dimensional growth crystallisation, volumetric crystallisation and homogeneous nucleation crystallisation, respectively [21,42]. The influence of main glass compositions on the crystallisation kinetics of the MAS glass samples was investigated using the Kissinger equation and Augis-Bennett equation [40][41][42][43][44], which are expressed as follows: ...
MgO–Al2O3–SiO2 (MAS) glass–ceramics with controllable crystalline phases were successfully prepared using the melting method followed by heat treatment. The effects of the main components of glass on the crystallisation kinetics, nucleation, crystallisation and properties of glass–ceramics were investigated in detail. As the Al2O3 and MgO contents increase and SiO2 content decreases, the crystallisation peak temperature and activation energy of MAS glass decrease, while the crystal growth tends to follow a homogeneous nucleation crystallisation. The MAS glass nucleation temperature and time increase with higher concentrations of Al2O3 and MgO and with a lower SiO2 concentration. Mg2(Al4Si5O18) indialite and MgAl2O4 spinel precipitate simultaneously in the MAS glass after crystallisation; the relative proportion of crystalline phases is related to the composition and crystallisation temperature. A higher SiO2 content allows the formation of a dominant indialite phase, while higher MgO and Al2O3 contents promote the formation of a dominant spinel phase. The MAS glass ceramic with a greater indialite phase has good dielectric properties with a dielectric constant of 6.499 and dielectric loss of 0.0064, while that of a higher spinel phase possesses improved mechanical properties, with a Vickers hardness of 715 Hv and a bending strength of 244.9 MPa.
... Thermal analysis is an appropriate method for studying the crystallization kinetics of glass-ceramic. Although a number of studies have been reported aimed specifically at examining the kinetic parameters (such as the crystallization activation energy and the Avrami index) using the non-isothermal kinetic methods in MAS glass-ceramics [15,16]. While the simultaneous characterization by multiple methods and the consistency of results on the relationship between the glass stability and crystallization need to be further studied. ...
... While the simultaneous characterization by multiple methods and the consistency of results on the relationship between the glass stability and crystallization need to be further studied. Of course, as a common nucleating agent, the effect of TiO 2 or ZrO 2 on the phase transformation, the structure and properties of MAS glass-ceramics has been studied in detail and developed [15][16][17][18][19]. However, the influence of TiO 2 -ZrO 2 codoping on the glass stability, crystallization behavior, structure, and performance of MgO-B 2 O 3 -Al 2 O 3 -SiO 2 glass-ceramics requires further research. ...
TiO2–ZrO2-codoped MgO–B2O3–Al2O3–SiO2 glass-ceramics were prepared using the traditional melting method. The effects of replacing TiO2 with ZrO2 on the glass stability (GS), crystallization behavior, structures, and properties of the obtained samples were studied. Results showed that the addition of ZrO2 increased the GS, which decreased the crystallization ability of the samples. When the heat treatment temperature was increased from 900 °C to 1000 °C, the mullite and quartz phases first precipitated in the glass matrix, and then converted into cordierite. Because of the low solubility of TiO2 and ZrO2 in this glass system, the rutile and zircon phases will precipitate from the parent glasses. Owing to changes in the composition and structure of the samples, the density and Vickers hardness increased, while the coefficient of thermal expansion of the samples first decreased and then increased when TiO2 was replaced with ZrO2.
... The formation of cordierite and phase transformation kinetics in cordierite materials [8,[25][26][27][28][29][30][31][38][39][40][41] were characterized by differential thermal analysis [28][29][30][31][38][39], differential scanning calorimetry [8,[39][40], and x-ray diffraction [8,[25][26][27]. Isothermal [25-27, 35] and non-isothermal [8, 25, 28-31, 38-41] experiments were carried out and activation energy values from 170 to 964 kJ/mol were reported [8,2,3,[25][26][27][28][29][30][31][38][39][40][41][42][43]. Recently, the authors synthesized low-cost stoichiometric [2] and non-stoichiometric [3] cordierite ceramic materials, by reaction sintering Algerian natural clay minerals and synthetic magnesia, and studied the effect of temperature and MgO on cordierite formation. ...
... Activation energy values for the formation of μ-cordierite and α-cordierite in NiO-added glass samples [30] were equal to 300 and 500 kJ/mol, respectively. Başaran and co-workers used industrial waste to prepare cordierite materials and obtained energy values of 410 kJ/mol [42] for cordierite formed in the titania doped magnesia-alumina-silica glass; and values of 336, 218, and 170 kJ/mol [43] for cordierite formed in the same system when Bi 2 O 3 was added at 2.5, 5, and 10 wt.%, respectively. This clearly shows that co-doping with TiO 2 and Bi 2 O 3 decreased the activation energy for cordierite formation in the magnesia-aluminasilica glass. ...
The effect of CaO on cordierite formation from kaolin-MgO-CaO powder
mixtures, milled for 5 h and reaction sintered for 2 h in the temperature
range 900-1400°C, was investigated. Phases formed in the developed
materials were characterized by x-ray powder diffraction method (XRD) and
Raman spectroscopy. Non-isothermal differential thermal analysis (DTA) and
thermogravimetric (TG) experiments were performed from room temperature to
1400°C, at heating rates from 20 to 40°C/min. Activation energies were
determined using Kissinger method. It was found that sintering the
stoichiometric kaolin-magnesia mixture led to the nucleation and growth of
monolithic cordierite; while cordierite along with anorthite were present in
the other two samples where 4 or 8 wt% of CaO was added. The increase in CaO
decreased cordierite formation temperature and increased the activation
energy, which ranged from 445 to 619 kJ/mol for μ-cordierite and from 604 to
1335 kJ/mol for α-cordierite.
... The formation of cordierite and phase transformation kinetics in cordierite materials [8,[25][26][27][28][29][30][31][38][39][40][41] were characterized by differential thermal analysis [28][29][30][31]38,39], differential scanning calorimetry [8,39,40], and X-ray diffraction [8,[25][26][27]. Non-isothermal [8,25,[28][29][30][31][38][39][40][41] and isothermal [25][26][27]35] experiments were carried out and activation energy values from 170 to 964 kJ/mol were obtained [2,3,8,[25][26][27][28][29][30][31][38][39][40][41][42][43]. The large variation in the obtained activation energies was attributed to the: "(i) nature and composition of precursors used to obtain cordierite, (ii) type of processes used to synthesize cordierite, (iii) conditions under which cordierite forms i.e. isothermal or non-isothermal, and (iv) presence of sintering aids to facilitate the formation of cordierite" [3]. ...
... Also, Başaran and co-workers showed that co-doping with TiO 2 and Bi 2 O 3 decreased the activation energy for cordierite formation in the magnesia-alumina-silica glass. They used industrial waste to prepare cordierite materials and obtained energy values of 410 kJ/mol [42] for cordierite formed in the titania doped magnesia-alumina-silica glass; and values of 336, 218, and 170 kJ/mol [43] for cordierite formed in the same system when Bi 2 O 3 was added at 2.5, 5, and 10 wt.%, respectively. In their work, Hu and Tsai [31] found that the energy for cordierite formation first increased and then decreased gradually with the increase in BaO content. ...
Low-cost, dimensionally stable, and hard cordierite ceramic materials were prepared by reaction sintering two Algerian natural clay minerals and synthetic magnesia. The microstructure and hardness of the developed materials were characterized by a scanning electron microscope and a hardness tester, respectively. Differential thermal analysis, dilatometry, and Raman spectroscopy were used to analyze the transformation of phases and sintering behavior. The coefficient of thermal expansion (α) was determined from dilatometry experiments. The microstructure of DT00M sample synthesized from stoichiometric powder mixture (clay minerals and synthetic magnesia) consisted of cordierite only. Whereas cordierite, magnesium silicate, and sapphirine phases were present in DT04M and DT08M samples prepared from non-stoichiometric powder mixtures containing excess magnesia of 16 and 20 wt.%, respectively. The values of the activation energy (Ea) and frequency factor (A), for cordierite crystals, varied from 577 to 951 kJ/mol, and 1.54 × 10¹⁸ to 1.98 × 10³⁰ S⁻¹, respectively. The kinetic parameter n for the formation of cordierite had values between 2 and 3. While the Gibbs free energy (ΔG#), enthalpy (ΔH#), and entropy (ΔS#) values were found to be in the range 431–483 kJ/mol, 564–938 kJ/mol, and 70–313 J/mol, respectively. Samples sintered at 1300 °C for 2 h showed higher values of hardness compared with those sintered at 1250 °C. The DT04M sample had the highest hardness value of 9.45 GPa, demonstrating an increase of 12.5% with respect to monolithic cordierite (DT00M). In the temperature range 100–1300 °C, DT04M and DT08M samples showed better dimensional stability compared to monolithic cordierite. The DT08M sample showed the lowest thermal expansion (α = 2.32 × 10⁻⁶/°C), demonstrating a decrease of 31.3% with respect to monolithic cordierite.
... One of the valuable substitute raw materials for the production of transparent or green container glass, and amber colour in particular, which gives the greatest potential to intensify melting process, is granulated metallurgical slag. The importance of blast-furnace slag lies in its chemical and phase composition [1]. Typical blast-furnace slag is composed of: 45-50% CaO + MgO; 35-40% SiO 2 ; 5-10% Al 2 O 3 . ...
A glass set with a high content of blast-furnace slag and a reduced amount of traditional raw materials requires optimization of the raw material composition and adjustment of its specificity to the temperature regime of melting, homogenizing and clarifying the glass mass. The introduction of an increased amount of blast-furnace slag allows to reduce the cost of raw materials: soda, limestone and high-class sand, reduce energy costs, whose consumption significantly decreases and reduces CO2 emissions in line with EU requirements. The tests of thermal analysis of a glass set with different contents of Calumite are aimed at learning the mechanism of its operation by determining the changes caused by its different presence in the course of subsequent reactions between the components of the glass set. Analysis of the influence of the addition of different Calumite slag contents treated as a substitute for the raw material on the melting process of glassware sets was analyzed. The tests were carried out using differential thermal analysis (DTA) and thermogravimetry (TG) based on the model glass [mass%]: 73.0% SiO2, 1.0% Al2O3, 10.0% CaO, 2.0% MgO and 14.0% Na2O. The effect of combining Calumite with sulphate and multi-component fining agent—mixtures of As2O3, Sb2O3, NaNO3 in proportions of 1:1:1 for chemical reaction and phase transformation, was investigated.
... where u [°C min -1 ] is the heating rate, E A [kJ mol -1 ] is the energy of formation, T p [°C] is the absolute peak temperature in DTA curves, and R is the gas constant. The Augis-Bennett equation [43][44][45][46][47] was used to calculate the kinetic parameter n: ...
The influence of temperature and magnesia content on the formation of phases and their transformation kinetics in stoichiometric and non-stoichiometric cordierite ceramics prepared from Algerian kaolinite precursors was investigated. High-temperature X-ray diffraction was used to study the formation of phases and their transformations. Non-isothermal differential thermal analysis was used to determine kinetic parameters for the formation of μ and α cordierite. Activation energies were calculated by Kissinger, Boswell, and Ozawa equations. The Augis–Bennett and Matusita equations were used to calculate the mode of crystallization (n) and dimension of growth (m) parameters, respectively. The synthesized materials showed similar phase transformations, which finally led to the formation of cordierite in stoichiometric kaolinite–magnesia mixture, and cordierite along with other phases in kaolinite–magnesia mixture containing excess magnesia. The activation energy for the formation of α cordierite was higher than that of μ cordierite. Energies of formation of μ and α cordierite phases in the non-stoichiometric samples were higher than those in the stoichiometric sample. The activation energy was less sensitive to the calculation method; however, it changed significantly with MgO content. Activation energies between 573 and 964 kJ mol⁻¹ were obtained. Magnesia changed the crystallization mode and crystal growth dimension. The kinetic parameters n and m, for the formation of μ or α cordierite, had values between 2 and 3.
... MgOeAl 2 O 3 eSiO 2 (MAS) glass-ceramics with cordierite (Mg 2 Al 4 Si 5 O 18 ) as the main crystalline phase have many excellent properties, such as low dielectric constant, low thermal expansion coefficient, good mechanical and chemical properties [1][2][3][4][5][6]. Therefore, these materials have been widely used in the fields of high voltage and high vacuum [7], microelectronic packaging [8,9] and glazes for floor tiles [10,11]. ...
... In recent years, there are many research works focused on utilizing industry solid wastes, such as fly ash, slags, and tailings to produce cordierite-based glass-ceramics [7,[12][13][14]. This method can not only reduce the production cost of these glass-ceramics, but also prevent or reduce environmental pollution by solid wastes, which has a good application prospect. ...
MgO-Al2O3-SiO2 glass-ceramics were prepared by melting method. The effects of replacement of Na2O by Fe2O3 on crystallization behavior and acid resistance of glass-ceramics were studied. The results showed that with Fe2O3 addition, the crystallization peak around 860 °C increased firstly and then decreased, while the peak around 1120 °C showed opposite changes. The crystallization peak around 1000 °C shiftted to low temperatures. With heat treatment temperature increasing from 880 to 1200 °C, μ-cordierite, spinel, sapphirine and α-cordierite precipitated successively in the glass samples. Fe2O3 had little effect on the type of crystal phases, but had a great influence on their crystallinity and precipitation temperature. After heat treatment at 1200 °C, the main crystalline phase changed from μ-cordierite to α-cordierite for the glass sample without Fe2O3. The addition of Fe2O3 promoted the crystallization of α-cordierite at low temperatures, especially for 1 mol% Fe2O3 doped sample, α-cordierite obviously precipitated at 1100 °C. All the base glass samples had poor acid resistance, which was greatly improved by heat treatment. When honeycomb structure α-cordierite appeared as the main crystalline phase, acid resistance deteriorated rapidly. A small amount of Fe2O3 addition reduced the acid resistance. With Fe2O3 content increasing, the acid resistance gradually improved.
... Plots of lnT p 2 versus 1/T p and lnT g 2 versus 1/T g are given in Fig. 4. The Avrami parameter (n) is calculated from the crystallization activation energy value (E a ) with the aid of Augis-Bennett equation (Eq. 3) [19,21,22]. ...
In the present work, CAS (CaO–Al2O3–SiO2)-based glass–ceramics were prepared by using Al2O3 (Seydişehir, Turkey) and pumice (Nevşehir, Turkey) as natural raw materials and marble dust (Sakarya, Turkey) as a waste source. CAS-coded composition (57.5 mass% SiO2, 27.5 mass% CaO, 15 mass% Al2O3) was selected in stoichiometric anorthite region according to the CAS ternary diagram. According to the DTA results at different heating rates, the crystallization activation energy of the glass that was prepared from the CAS-coded composition was calculated to be 373 ± 5 kJ mol⁻¹ and the viscous flow activation energy to be 430 ± 8 kJ mol⁻¹.
