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Non‐isothermal thermogravimetric analysis in air, of polyoctenamer‐single wall carbon nanotubes (PO‐SWNTs), loaded by various amounts of SWNTs up to 10% wt., at different heating rates (ranging from 5 to 40°C/min) is reported. The thermal degradation in the air of PO_SWNTs is dominated by a main single sigmoidal dependence, assigned to the polymer and eventually polymer‐nanofiller interphase, over which a weaker sigmoid assigned to the thermo‐oxidative degradation of the nanofiller is superimposed at higher temperatures. The temperature at which the nanocomposite's residual mass fraction reaches x% wt. of the initial mass, Tx%, is reported (for x = 5, 50, and 85). The dependence of Tx% on the heating rate and the loading by nanotubes is analyzed. The temperature derivative of the thermograms defines new parameters (inflection residual mass fraction and inflection temperature) and (degradation) width. Their dependence on the loading by SWNTs was reported. Estimation of the interphase in polymer‐based nanocomposites is based on the postulate that the dependence of the inflection temperature on the composition of the nanocomposite obeys a Fox‐like dependence, where the bulk polymer and the polymer trapped within the interphase are considered as a blend of two miscible polymers. Complementary Raman, x‐ray diffraction, and differential scanning calorimetry support these results. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis (TGA) is a powerful technique and useful method for characterizing biomass as a non-conventional fuel. A TGA apparatus has been utilized to experimentally investigate the impact of biomass feedstock diversity on the performance of the gasification of hardwood (HW), softwood (SW) pellets, and refuse-derived fuel (RDF) materials. The solid conversion rate and the volatile species formation rate have been estimated to quantify the rates of devolatilization for each material. In addition, the combustion kinetic characteristics of the three biomass feedstocks were investigated using TGA at different heating rates, and a thermal kinetic analysis was conducted to describe the gasification process. Therefore, the kinetic parameters have been evaluated for different thermal reactions and non-isothermal kinetic models that depend on the relationships between heating rates and temperature profiles. The results show that the amount of tar content from the RDF was higher than that of pure hardwood and softwood feedstocks. Hence, tar removal must be part of any process using syngas produced from RDF feedstocks in a gas engine to produce electricity. [ABSTRACT FROM AUTHOR]

Bamboo powder has a high risk of fire and dust explosion during production, manufacturing, transportation and storage. It is of great significance to study the combustion characteristics of bamboo powder and its influencing factors for finding suitable flame retardants. So far, the relative study is more focused on bamboo rather than bamboo powder. In this paper, the combustion characteristics of bamboo powder were measured by TGA. Ignition temperature, burnout temperature, combustion rate and comprehensive combustion index were used as evaluation criteria. The influence of particle size and heating rate was quantitatively analyzed. The results showed that the ignition and burnout temperature increased with the increase in heating rate. The S value at the heating rate of 40 °C min−1 was 22 times of that at 5 °C min−1. The finer the particle size, the higher the S value, and the S value of 400-mesh bamboo powder can reach 2.0 × 10–5. The flame retardant properties of six inorganic compounds on bamboo powder were studied. According to the S value, the order of flame retardant properties at the best concentration was CaCl2 ˃ NH4H2PO4 ˃ MgCl2 ˃ Na3PO4 ˃ NH4Cl ˃ APP. Among them, 33% CaCl2 had the best flame retardancy. [ABSTRACT FROM AUTHOR]

Energy demands are dynamic and intensifying demand of energy led to execute this study in order to analyze the thermal degradation characteristics of Melia azedarach sawdust (MAS) collected from sawmill intending to examine its pyrolytic performance for biofuel production. The inceptive characterizations which include proximate, ultimate, component analysis and higher heating value (HHV) were carried out so as to scrutinize its worth for pyrolysis. Furthermore, thermogravimetric (TG) experiments were performed in temperature hovering from ambient to 900 ℃ at three different slow rates of heating (10, 20 and 30 ℃ min−1) under inert condition. Findings of TG analysis revealed 210 to 480 ℃ as the maximum devolatilization temperature range during thermal degradation of MAS. Kinetic and thermodynamic parameters were estimated using three iso-conversional models, i.e. Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO) and Starink and average activation energy was found to be 161.18, 162.68 and 161.41 kJ mol−1, respectively. The obtained values of Gibbs free energy (ΔG) were 185.98, 185.91 and 185.97 kJ mol−1 and that of change in enthalpy (ΔH) were 155.91, 157.47 and 156.19 kJ mol−1 for KAS, FWO and Starink models, respectively. Master plot along with Criado method revealed a complex mechanism of the reaction. Average and maximum decomposition rates, as well as initial devolatilization and peak temperatures, shifted to higher values with an increase in heating rate. Comprehensive pyrolysis index (CPI) exhibited higher value at higher heating rate which indicates the suitability of pyrolysis of MAS at a high heating rate. All these findings coupled with 15.43 MJ kg−1 HHV inferred the suitability of MAS for pyrolysis as it exhibits remarkably high potential for biofuel generation. Thus, it can be a concrete step towards clean energy generation along with a balance between economy and ecology with desire to strengthen our energy self-sufficiency. [ABSTRACT FROM AUTHOR]

The focus of this study is on the synthesis of organic fluorescent and thermally stable polyamides using an s-triazine frame. Coumarin and n-phenyl anthranilic acid have been utilized as bulky pendent groups in the synthesis of the monomer, resulting in polyamides with two groups that enhance stability and fluorescence. The synthesized polyamides have been characterized using a variety of techniques. The thermal stability of the polyamides has been studied using thermogravimetric analysis. These polyamides offer appealing features such as fluorescence and enhanced thermal stability, making them significant for a wide range of applications, including biosensors, clean energy technologies, and explosive sensing. [ABSTRACT FROM AUTHOR]

In this study, Oriental beech (Fagus orientalis L.) wood was treated with 0.5%, 1.5% and 4.5% concentrations of two different dimensional stability chemicals (glyoxal and glycerol), two different fire-retardant salts (sodium acetate and sodium pentaborate), and their mixtures (1:1; weight/weight). The thermal degradation properties of wood samples treated with different types and concentrations of compounds were investigated using thermogravimetric analysis (TGA). When only glyoxal or glycerol was used, they had an adverse effect on the thermal properties of samples. The use of these chemicals together improved the thermal properties, due to the formation of longer polymer chains compared with the control group. Sodium acetate and sodium pentaborate salts, both singly and in a mixture, improved the char yield. The highest char yield (72.13%) was obtained using sodium pentaborate at 4.5% concentration. [ABSTRACT FROM AUTHOR]

Phenylboronic acids (PBAs) form stable complexes with fluoride. The effect of type (methoxy-, formyl-, and acetyl-) and position (ortho-, meta-, and para-) of electron-donating substitutions on the hydrolytic stability and acidity of PBAs, as well as their spectroscopic and physicochemical properties and their usage in spectrofluorimetric fluoride determination, were investigated. Thermal stabilities, relative predisposition, and resistance to dehydroboronation of related PBA isomers were investigated in detail and compared with the use of thermogravimetric analysis and differential scanning calorimetry profiles. Dehydroboronation reaction leads to the synthesis of related new cyclic anhydric forms — specifically named boroxines — which are clearly distinguished by Fourier transform infrared spectroscopy. PBAs were used for the complexation of fluoride for spectrofluorimetric fluoride determination in dental formulations [toothpastes (TPs) and mouth rinses (MRs)] and beverages [mineral waters (MiWs)]. Determination was done by fluorescence quenching of PBAs in response to increasing fluoride concentration. The regression equation was y = –15.336x + 983.17 (R2 = 0.9931), and was linear in the 1.4–3.0-mM range. Determinations were performed with relative errors (%) in a range of –5.60 to +1.23, –2.01 to +5.69, and –4.16 to +2.54 for MRs, TPs, and MiWs, respectively, relative to fluoride levels of commercial samples. Chemometric analyses (cluster analysis, CA, principal component analysis, PCA) were performed on the same real samples. Raw fluorescence data was investigated by PCA to check their significance in chemometric discrimination. Dendograms and score plots successfully discriminated samples in related groups. This is the first demonstration of spectrofluorometric fluoride determination based on the quenching of related isomers of PBAs thus far, also the potential of raw fluorescence data of these PBAs for chemometric discrimination studies on related pharmaceutical samples was highlighted for the first time. [ABSTRACT FROM AUTHOR]

The subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance liquid chromatography, coupled with diode array and tandem mass spectrometry detectors with electrospray ionization (HPLC-DAD-ESI-MS/MS) facilitated the detection and identification of colorants present in the textiles. Cochineal, indigo-, madder-, orchil-, and tannin-producing plants were identified as the sources of dyes used. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was employed to identify and characterize the silk fibers and mordants and the metal threads. The presence of iron, aluminum, sodium, and calcium in the silk threads suggests their potential use as mordants. The analysis of the metal threads revealed that most of them were made from flattened gilded silver wire, with only a few being cut from a sheet of metal. Typical degradation mechanisms of metal threads were shown, resulting from both burial environment and earlier manufacturing process, and the use of the textiles in clothing, i.e., a significant loss of the gold layer was observed in most of silver gilt threads, caused by abrasion and delamination. The results of the thermal analysis confirmed the presence of silk and silver threads in the examined textiles. [ABSTRACT FROM AUTHOR]

Phosphorylated cellulose can be an intrinsic flame retardant and a promising alternative for halogenated fire inhibitors. In this study, the mixture of di-ammonium hydrogen phosphate (DAP) and urea (U), containing phosphate and nitrogen groups, was applied to attain fire inhibitor properties. Functional groups of cellulose were grafted with phosphorous by keeping the constant molar ratio of 1/1.2/4.9 between anhydroglucose units of cellulose/DAP/U in different concentrations of bleached kraft pulp. Phosphorus concentrations were determined using the ICP hrOES method, and paper sheets were made using the Rapid Köthen apparatus. The tensile strength of phosphorylated cellulose increased twice compared with unmodified cellulose when the phosphorous concentration increased to 10,000 g/kg. An increase in the tensile index comes from the higher freeness of pulp and cross-linking of the phosphorous group between cellulose fibers. Remarkable fire retardancy effects were achieved in cellulose concentrations above 5 wt%. The raised phosphorous concentration above 10,000 g/kg due to the phosphorylation process caused the formation of a char layer on a cellulose surface and the nonflammable gas emission. That effect was indirectly confirmed by reducing the combustion temperature and HRR by 50 and 45%, respectively. Due to increasing phosphorus concentration in cellulose sheets, cellulose's fire and strength properties increased significantly. [ABSTRACT FROM AUTHOR]

To evaluate the effect of different wall material (WM) matrices followed by homogenisation to encapsulate chia seed oil (CSO) using freeze drying technology. CSO was encapsulated using three ratios (100/0, 50/50, and 100/0) of two WM matrices: MTS/WPC (modified tapioca starch–whey protein concentrate) and MD/WPC (maltodextrin–whey protein concentrate). The evaluation included encapsulation efficiency (EE), oxidative stability, and α-linolenic acid (ALA) retention. Homogenised microcapsules (-H) were then assessed for storage and thermal stability, along with cumulative oil release. The MD-WPC-H 50/50 microcapsules had superior EE (97.32%), higher ALA retention (60.2%), storage stability (up to 30 days), higher thermal stability (up to 700 °C), and desirable oil release in simulated condition. Selecting suitable WM and homogenisation is key for improving EE, storage, thermal stability, and targeted release. The CSO microcapsule can serve as a functional ingredient to improve the quality of diverse food products. [ABSTRACT FROM AUTHOR]

The production of pottery in East Asia can be traced back to approximately 20,000 years ago. Hunter-gatherer communities utilised pottery for many years before transitioning to agriculture in regions such as China, Japan, and the Russian Far East. While there has been much debate surrounding pottery production in hunter-gatherer societies, little attention has been given to the role of ceramic vessels in the shift to sedentism and agriculture. This research explores the technological aspects of pottery production in both hunter-gatherer societies and societies in the midst of transitioning to agriculture. The study focuses on ceramic assemblages from two sites in the Fuxin Area of Liaoning province, China. The earlier site represents a small semi-sedentary society that relied solely on hunting and gathering, while the later site, around 400 years later, is a village that also incorporates the use of millet. Using petrography, X-ray diffractometry, X-ray florescence, and thermo-gravimetric analyses, the study identifies differences in ceramic production between the two sites, including the use of selective clay and temper types and improved firing techniques at the later site. These technological changes are believed to be due to specific changes in the preferences of sedentary groups, possibly related to food processing during the onset of agriculture. The findings shed light on the relationship between social, economic, and technological variation in prehistoric societies. [ABSTRACT FROM AUTHOR]

Changes in water content have a significant impact on the consolidation of peat soil. Through the water content test and thermogravimetric analysis test, the water content, and the free water, weakly bonded water and strongly bonded water content of peat soil with different organic content in Yunnan Province (China) at different load levels and consolidation times were studied. The results show that the free water in peat soil samples was discharged when the temperature was less than 60 °C; the weakly bound water was released at 60 − 110 °C; and the strongly bound water was dehydrated at 110 − 200 °C. During the consolidation of peat soil, the water content in different states changed significantly. In the primary consolidation stage, the proportion of free water in the peat soil samples decreased by approximately 20%, while the proportion of weakly bound water increased slightly. In the secondary consolidation stage, the proportion of water in different states did not change considerably. In the third consolidation stage, the proportion of free water increased, and the proportion of weakly bonded water causing creep decreased by approximately 11%. For the undisturbed and deformed peat soil, the contents of free water and bound water increased with increasing total water content, but the ratio of free water to bound water remained relatively stable at approximately 1:2. [ABSTRACT FROM AUTHOR]

Background. Coordination compounds can exhibit phase transitions: dissolution, solvation loss, desolvation, dehydration, and polymorphic transitions. Understanding them is important for optimizing the synthesis process, controlling crystal growth, and studying the state of coordination compounds in various environments. Purpose. Synthesis of a complex compound containing [Mn(BZA)4Cl2], its thermogravimetric and differential thermal analysis. Methodology. During the synthesis process, a magnetic stirrer was used and studied by thermogravimetric and differential thermal analysis (Model: KL-JS-100A). Originality. The conditions for the synthesis of coordination compounds with the general formula [Mn(BZA)4Cl2] were identified and their structure was determined by physical research methods. Findings. Having performed TGA and DTA of the metal complex, we gained an understanding of its thermal stability, behavior during decomposition and thermal phenomena, which can be used to determine the properties of the complex and prospects for use. [ABSTRACT FROM AUTHOR]

In order to explore the influence of pickling on the pyrolysis characteristics and adsorption performance of biomass, this paper used pickled rice husk as raw material, and used TG-FTIR coupling instrument to explore the pyrolysis characteristics and product changes of rice husk; The Coats-Redfern (C-R) method was used to analyze the pyrolysis kinetics, and the adsorption performance of pyrolysis biochar on heavy metal Cu was investigated. The results show that pickling can effectively reduce AAEMs, change the pyrolysis path, increase the release of volatiles, and increase the calorific value of raw materials by about 17.10%. The surface of rice husk retains abundant functional groups, and the vibration of characteristic peaks is more intense. The C-R kinetic analysis showed that the pyrolysis process was consistent with the reaction order n = 1, and the influence on the activation energy of rice husk was sulfuric acid > phosphoric acid > nitric acid. The pickling pyrolysis biochar can promote the adsorption of heavy metal Cu2+ in the aqueous phase, the adsorption capacity is up to 41.4 mg·g-1, and the adsorption efficiency is up to 82.8%. [ABSTRACT FROM AUTHOR]

It is well known that lubricating oils reduce the friction coefficient between two surfaces in contact. Since petroleum lubricants are toxic and have a low biodegradability, they are typically not appropriate for the environment. As a result, as public worries about a pollution-free environment grow, so does the demand for lubricants that are acceptable to the environment. The primary rationale for utilizing vegetable oils in forthcoming bio-lubricant formulations is their high lubricating performance, low toxicity, sustainable, and biodegradability. Plant oils hold great potential as a foundational fluid for bio-lubricants, since their synthetic and vegetable oil-based esters provide the most environmentally friendly option for creating lubricants. In this study, Jatropha and Jojoba raw oil were chemically modified via epoxidation followed by transesterification to produce bio-lubricants. Thus, the aim of this work is to develop a bio-lubricant from jatropha and jojoba methyl ester, further adding nanoparticles multiwalled nanotubes and titanium dioxide for improvement of tribological properties. The chemical modification of the jatropha and jojoba oil results in a decrease in iodine value, resulting in the breaking of carbon bonds. Viscosity tests were performed using the Anton Par MCR 92 Rheometer, with temperature ranging from 30°C to 80°C. Thermal stability measurements of bio-lubricants were performed using PerkinElmer’s Thermogravimetric analyzer-4000 instrument and thermal degradation temperature for Epoxidized Jatropha-sulfuric acid, Epoxidized Jatropha-hydrochloric acid, Epoxidized Jojoba-sulfuric acid and Epoxidized Jojoba-Hydrochloric acid samples are 238°C, 224°C, 230°C, and 244°C, respectively. The 94.68% and 79.85% reduction in wear was obtained for Epoxidized Jojoba with hydrochloric acid, titanium dioxide and epoxidized Jatropha with sulfuric acid, multiwalled carbon nanotubes in comparison with their epoxidized samples. The coefficient of friction of Epoxidized Jatropha with sulfuric acid, multiwalled carbon nanotubes and Epoxidized Jojoba with Hydrochloric acid, Titanium dioxide sample was found to be 0.061 and 0.059, respectively [ABSTRACT FROM AUTHOR]

Robust mathematical treatment of the Ozawa/Flynn/Wall isoconversion method is conducted to determine the value and uncertainty of the activation energy and pre‐exponential factor for the degradation of polypropylene in thermogravimetric analysis experiments at constant heating rates. The present work employs mathematical models and uncertainty propagation techniques based on the Guide to the Expression of Uncertainty in Measurement to estimate the Arrhenius activation energy and pre‐exponential factor due to the uncertainty of the integration constant b, both in a linear and a third‐degree reciprocal polynomial model with respect to x. The error arising from Doyle's linear approximation in the improper integral of temperature in the Arrhenius equation is examined, and an alternative method is proposed to correct this error, reducing it to 0.032% in the working interval of −200 ≤ x ≤ −15, where x = −E/RT. Given the increased sensitivity of modern thermogravimetric analysis equipment, these improvements are considered essential for obtaining reliable results that align with experimental precision limits compared to previous works. Thus, this allows for the development of an enhanced quality assurance framework by providing more robust uncertainty estimation and a better understanding of the method. Moreover, this approach can be applied to other similar polymer system. [ABSTRACT FROM AUTHOR]

New transition metal complexes of cobalt(II), nickel(II), copper(II) and zinc(II) with new Schiff base [HLp] derived from pyrene-1-carbaldehyde and 4-Amino-3-mercapto-5-oxo-1,2,4-triazine were synthesized and characterized by elemental analysis, 1H-NMR, FT-IR, UV-Visible, ESR spectral studies, magnetic moment measurements and cyclic voltammetry. Results prove that [HLp] acts as bidentate ligand. Low conductance data reveal non-electrolytic nature of the complexes. The spectroscopic data and magnetic moment values along with elemental analytical data support octahedral geometries for Co(II), Ni(II), Zn(II) complexes and square planar geometry for Cu(II) complexes. ESR spectra of Cu(II) complexes exhibited g values trend as g ∥ > g ⊥ > g e. The nephelauxetic ratio (β) along with orbital reduction factors (K values) report the covalent nature of the metal-ligand bonds in complexes. Thermal analysis was also carried out to propose the composition of complexes and to determine their thermal stability. Coats-Redfern method was employed to evaluate some kinetic parameters of thermal degradation processes. In vitro antimicrobial properties of all synthesized compounds were investigated. After assessing the inhibition zones, metal complexes have been found more antimicrobial active than the Schiff base against both bacterial as well as fungal strains. Metal complexes also showed remarkable fluorescence and antioxidant properties. [ABSTRACT FROM AUTHOR]

The solubility of the components in the ZnSO4 - KNO3 - H2O system was studied by the visual-polythermal method in the temperature range from -7.0°C to 42.0°C. The phase diagram delimits the fields of ice crystallization, KNO3, K2SO4·ZnSO4·6H2O, and ZnSO4. A solubility diagram was constructed, and a new compound K2SO4·ZnSO4·6H2O was separated. The new compound was identified by chemical, X-ray phase, thermogravimetric, and IR spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Solid fossil fuels still support the development of the energy and chemical industry. The clean and efficient utilization of solid fossil fuels can effectively alleviate the problems of energy shortage and environmental pollution. An in‐depth understanding of the kinetic process, models, and mechanism of pyrolysis of solid fossil fuels is also of great significance for the exploration and utilization technologies of petroleum resources. Thermogravimetric analysis is an effective method to study the pyrolysis process and kinetics with the advantages of high sensitivity, repeatability, and reliability for data acquisition. Researchers have conducted a lot of research on the thermogravimetric kinetics of solid fossil fuels in recent years, but there is a lack of systematic summary and comparison of kinetic methods, research progress, and trends. Therefore, a comprehensive study on pyrolysis kinetic principles, methods, and models of solid fossil fuels by thermogravimetric analysis is carried out in this paper. The influencing factors of pyrolysis kinetics of solid fossil fuels using thermogravimetry are elaborated and discussed in detail. This study also provides progress in recent years and prospects of thermogravimetric kinetics of solid fossil fuels. It is expected that this paper can provide certain technical support and theoretical guidance for the research on pyrolysis kinetics based on thermogravimetric analysis, and the exploration and development, clean, and efficient utilization of solid fossil fuels. [ABSTRACT FROM AUTHOR]

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This paper is devoted to studying the thermochemical properties of carbon sources (laboratory-scale conventional coke, biocoke with 5 wt.%, and 10 wt.% wood pellet additions) and the influence of these properties on foamy slag formations at 1600 °C. Thermogravimetric analysis (TGA) conducted under air unveiled differences in mass loss among carbon sources, showing an increasing order of coke < biocoke with 5 wt.% wood pellets < biocoke with 10 wt.% wood pellets. The Coats–Redfern method was used to calculate and reveal distinct activation energies among these carbon sources. Slag foaming tests performed using biocoke samples resulted in stable foam formation, indicating the potential for biocoke as a carbon source to replace those conventionally used for this process. Slag foaming characters for biocoke with 5 wt.% wood pellets were improved more than coke. Using biocoke with 10 wt.% wood pellets was marginally worse than coke. On the one hand, for biocoke with 5 wt.% wood pellets, due to increased reactivity, the foaming time was reduced, but it was sufficient and optimal for slag foaming. Conversely, biocoke with 10 wt.% wood pellets reduced foaming time, proving insufficient and limiting the continuity of the foaming. This study highlights that thermochemical properties play a significant role, but comprehensive assessment should consider multiple parameters when evaluating the suitability of unconventional carbon sources for slag foaming applications. [ABSTRACT FROM AUTHOR]

Pyrolysis stands out as one potential route for valorizing abundant agro-industrial cocoa residues. However, the products of this reaction, particularly bio-oil, do not possess the required quality for direct use in many applications. Thus, this study explores the use of iron sulfate and zinc sulfate as potential catalysts in the pyrolysis of these residues. In this investigation, the biomass, previously ground and dried, was impregnated with varying percentages of ferric sulfate and zinc sulfate. The TG-FTIR technique was employed to ascertain the effect of these salts on the pyrolysis of cocoa shell. The results were fitted with the DAEM model with three pseudo-components. It was determined that both salts induced alterations in the DTG profiles of the thermal decomposition of cocoa shell. In the evolved gases, compounds such as CO2, H2O, CH4, CO, HCN, and oxygenated compounds like HCOOH and CH3COOH were detected. Ferric sulfate significantly influenced the activation energies governing the reactions of the three pseudo-components. Conversely, the presence of zinc sulfate did not alter the activation energies associated with the decomposition of cocoa shell pseudo-components. Both catalysts induced alterations in the infrared spectra of the evolved gases, which is primarily evident in the relative intensities of bands corresponding to the stretching vibrations of constituent groups within CO2, CO, water, and oxygenated compounds.

This study investigates the intricate thermal decomposition behavior and combustion characteristics of two distinct types of wheat straw pellets (WSP) represented as T1 (100 % wheat straw) and T5 (70 % wheat straw; 10 % sawdust, 10 % biochar; 10 % bentonite clay). Through a thermogravimetric analyzer (TGA) the pellets undergo combustion under varying heating rates (5, 10, and 20 °C/min) in an air atmosphere, ranging from 25 to 1200 °C. Differential thermogravimetric and thermogravimetric analyses reveal four distinct stages of decomposition in the biomass components. The results indicate that the optimal combustion heating rate is 20 °C/min, resulting in the highest reaction rate (∼50 %/min) and most substantial mass loss (∼55 %) for both T1 and T5 pellets. Notably, the T5 pellet demonstrates a lower ignition temperature (207 °C, at 20 °C/min) and higher burnout (457 °C at 10 °C/min) compared to the T1 pellet, indicating its superior suitability for combustion. The combustion efficiency ranges from 61.0 to 99 % within the temperature range of 300 to 700 °C, similar to coal combustion. Additionally, thermodynamic properties (Di, Db, C, and S) suggest the promising potential of WSP as a bioenergy feedstock. Furthermore, T1 pellets demonstrate higher ignition temperatures (Ti) than T5, indicative of rapid combustion and lower energy potential. burnout temperatures (Tb) revealed intricate results in both scenarios. These findings hold significance for the design of gasification or combustion reactors and the industrial utilization of WSP biomass. The insights gathered from this study offer valuable guidance for designing and enhancing bioenergy systems and fostering sustainable practices in utilizing agricultural residues for energy production.

Solid waste management is one of the biggest challenges of the current era. The combustible fractions in the waste stream turn out to be a good energy source if converted into refuse-derived fuel. Researchers worldwide are successfully converting it into fuel. However, certain challenges are associated with its application in gasifiers, boilers, etc. to co-fire it with coal. These include high moisture content, low calorific value, and difficulty to transport and store. The present study proposed torrefaction as a pretreatment of the waste by heating it in the range of 200 °C–300 °C in the absence of oxygen at atmospheric pressure. The combustible fraction from the waste stream consisting of wood, textile, paper, carton, and plastics termed as mixed waste was collected and torrefied at 225 °C, 250 °C, 275 °C, and 300 °C for 15 and 30 min each. It was observed that the mass yield and energy yield decreased to 45% and 62.96% respectively, but the energy yield tended to increase by the ratio of 1.39. Proximate analysis showed that the moisture content and volatile matter decreased for torrefied samples, whereas the ash content and fixed carbon content increased. Similarly, the elemental analysis revealed that the carbon content increased around 23% compared to raw samples with torrefaction contrary to hydrogen and oxygen, which decreased. Moreover, the higher heating value (HHV) of the torrefied samples increased around 1.3 times as compared to the raw sample. This pretreatment can serve as an effective solution to the current challenges and enhance refuse-derived fuel's fuel properties.

Biomass is an organic substance widely available in nature as a fresh or a waste material considered renewable energy that aligns with the zero-carbon scheme to reduce the dependency on fossil fuels. However, after conversion, biomass's physical or chemical properties highly affect biofuel characteristics. A variety of instruments can be used to figure out biofuel reactivity. Considering commonly adopted instruments, thermogravimetric analysis (TGA) is a simple, fast, and efficient way to determine biofuel properties and reactivity. The TGA method has the capability to analyze the biofuel properties (proximate analysis: moisture, volatile matter, fixed carbon, and ash) and combustion features of biomass (such as ignition, reactivity, etc). Most importantly, the TG curvatures (TGA and DTG) reveal the behavior of the biofuel during the thermodegradation process. As a consequence, the quality and quantity analyses on the biofuel properties and reactivity can be investigated comprehensively. Moreover, some TGA integration with artificial intelligence (AI) has been studied to better understand biofuel management and technology for future development. The outcome for the TGA-AI integration may obtain an excellent result with the fit quality value R2 >95 %. This study aims to comprehensively review relevant research using TGA to analyze the lignocellulosic biofuel properties and reactivity. Moreover, the discussion in this study is extended to perspective, challenges, and future work.

Thermogravimetric and kinetic analysis of biomass and plastic co-pyrolysis can provide valuable inputs for a better understanding of decomposition mechanisms. Such inputs are important for selecting the appropriate process conditions but can also be helpful for process modelling. This work investigates the properties of heterogenous sawdust in a mixture with polypropylene and polystyrene. Thermogravimetric analysis is conducted to determine the decomposition mechanism and kinetic parameters of investigated mixtures and to derive appropriate conclusions regarding their further utilization potential. Co-pyrolysis was performed on mixtures with the following biomass/plastic ratios: 75-25%, 50-50%, 25-75%, over a temperature range of 30-550 °C, at four heating rates 5, 10, 20, and 30 °C/min, with pure argon as a carrier gas. Obtained results were then subjected to comprehensive kinetic and thermodynamic analysis. The primary goal was to determine effective activation energies using model-free methods, pre-exponential factors, and elementary thermodynamic parameters such as changes in enthalpy, entropy, and free Gibbs energy. Finally, the influence of the heating rate and mixture composition was extensively investigated by analyzing calculated parameters.

Thermal analysis methods, primarily thermogravimetric analysis (TGA), play an important role in the study of phase transitions and degradation of active food components and auxiliary substances during heating or cooling. The most important areas of application of TGA in the food industry include the analysis of patterns of changes in the mass of the studied system during its heating or cooling due to the presence of phase transitions of the first kind and chemical reactions. In this work, a study of the change in mass of biscuit products during heating was carried out. The effect of replacing wheat flour with cricket flour in the amount of 5.0% on the structure of the resulting biscuit product compared to the control was determined. This study showed a change in the distribution of forms of connection of system water with dry substances of the system and, as a result, an expansion of the range of temperatures at which water evaporation from this sample took place. However, with a further increase in the amount of cricket flour in the recipe, which has an increased protein content, an increase in the part of the system water associated with the proteins of this raw material was observed. As a result, the range of temperatures at which water evaporation occurred from biscuit products with cricket flour in the amount of 10.0% and 15.0% decreased. It was noted in the work that the most acceptable functional and technological property of biscuit products is a wider range of forms of connection of system water with dry substances of such food products, since the presence of different forms of connection of water significantly determines the organoleptic indicators of finished products, terms and conditions its storage. The results obtained by the method of thermogravimetric analysis showed that, from the point of view of expanding the spectrum of forms of connection of system water with dry substances of the studied samples, the sample with the replacement of wheat flour with flour from crickets in the3 amount of 5.0% should be considered more acceptable.

Nanofibrillated cellulose (NFC) consists of ultrafine cellulose structures in which the fibrils can have widths in the range from about 5 to 100 nm. NFC has been studied and developed in the paper industry, using bleached pulp from wood as the raw material. One of the issues in the application of NFC is their heat resistance to thermal degradation. The production process of NFC results in a decrease in their pyrolysis temperature during the nanofibrillation of bleached pulp; however, the details behind the reason and mechanisms are still unclear. In this study, NFC was prepared from bleached hardwood and softwood pulp by mechanical nanofibrillation using a grinder, and the pyrolysis behavior was investigated. For both bleached pulps, a decrease in the pyrolysis temperature was observed after nanofibrillation. The results suggest that the decrease in the pyrolysis temperature from nanofibrillation is not due to damage of the crystalline cellulose by nano fibrillation, but the damage of the hemicellulose components in the surface of the cellulose microfibrils or the interface between the crystalline cellulose and hemicellulose. If the hemicellulose on the surface of crystalline cellulose could be removed from the NFC, then the decrease in the pyrolysis temperature could be suppressed.

We synthesized four new copper(II) complexes with acetato and chlorido ligands and methylammonium (MA), dimethylammonium (DMA), and tetramethylammonium (TMA) counterions: (MA)4[Cu2Ac4Cl2]Cl2·2H2O (1), (DMA)2[Cu2Ac4Cl2] (2), (DMA)4[Cu2Ac4Cl2]Cl2·2H2O (3), and (TMA)5[Cu2Ac4Cl]Cl4·4H2O (4). All compounds were characterized by single-crystal X-ray diffraction, magnetic measurements, FTIR spectroscopy, and thermogravimetric analysis. Complexes 1, 2, and 3 consist of a dinuclear coordination anion [Cu2(Ac)4Cl2]2− with bridging acetato ligands arranged in a paddle-wheel conformation and square-pyramidal coordination around Cu(II) atoms, while the coordination anion in compound 4 is a polymeric chain, parallel to the c axis, with Cu2(Ac)4 units connected through bridging chlorido ligands. Magnetic measurements carried out between 2 K and 300 K indicate strong antiferromagnetic interactions between Cu(II) ions. The effective magnetic moments range from 1.94 μB to 2.21 μB, exceeding the spin-only value for Cu(II) ions (μeff=1.73 μB) and suggesting significant orbital contributions to the magnetic moment. Thermogravimetric analysis of all complexes showed a multistep decomposition behavior yielding elemental copper as the final product.

The development of wind power has brought about increasing challenges in decommissioning, among which DWTBs (decommissioned wind turbine blades) are the most difficult component to deal with. To enable the cost-effective, energy-efficient, and environmentally friendly large-scale utilization of DWTBs, an experimental study on thermogravimetric and pyrolysis characteristics of DWTBs was carried out. A new process involving recycling glass fiber with pyrolysis gas re-combustion and flue gas recirculation as the pyrolysis medium was innovatively proposed, and the simulation calculation was carried out. Thermogravimetric experiments indicated that glass fiber reinforced composite (GFRC) was the main heat-generating part in the heat utilization process of blades, and the blade material could basically complete pyrolysis at 600 °C. As the heating rate increased, the formation temperature, peak concentration, and proportion of combustible gas in the pyrolysis gas also increased. The highest peak concentration of CO gas was observed, with CO2 and C3H6 reaching their peaks at 700 °C. The solid product obtained from pyrolysis at 600 °C could be oxidized at 550 °C for 40 min to obtain clean glass fiber. And the pyrolysis temperature increased with the increase in the proportion of recirculation flue gas. When the proportion of recirculation flue gas was 66%, the pyrolysis temperature could reach 600 °C, meeting the necessary pyrolysis temperature for wind turbine blade materials. The above research provided fundamental data support for further exploration on high-value-added recycling of DWTBs.

Objective The content and existence form of bound water have an important influence on the physical and mechanical properties of red clay, and macroscopic shrinkage of red clay leads to microstructure changes of soil particles, pores and bound water, which in turn may cause soil surface cracking, triggering infiltration, destabilization, and other engineering geological problems. Methods Thermogravimetric analysis tests, BET tests, scanning electron microscopy (SEM) and zeta potential tests were conducted to study the variation characteristics of bound water during the shrinkage of undisturbed red clay. The structural model of spherical and lamellar clay particles based on the uniform distribution of bound water film was established, and the formula for the calculation of bound water film thickness was derived. Results The results showed that most of the water in undisturbed red clay exists in the form of bound water and the loss of weakly-bounded water continues throughout the shrinkage process of red clay. During the process, the zeta potential, specific surface area and the thickness of the bound water film decreased continuously. Conclusion The results reveal the intrinsic mechanism of water loss and shrinkage of red clay, which can provide theoretical support for solving environmental engineering geological problems.

Tetra Pak® paper and PE (polyethylene) wastes were evaluated to obtain a new composite material with awareness of environmental responsibility. Fillers and coupling agents were used for this joining process. Calcite (CaCO3), boric acid (H3BO3), SPT (Sodium Perborate Tetrahydrate / NaBO3.4H2O), titanate, MAPE (maleic anhydride grafted polyethylene, and vinyltriethoxysilane (C8H18O) composites were produced in 30 × 30 cm plates. A total of 30 samples were prepared as 5 mg flour for thermogravimetric analysis (TGA). Samples were observed in a thermal analyzer at 10, 15, or 20 °C/min heating rate in nitrogen atmosphere. Graphs were obtained as a result of TGA, and the activation energies were calculated using these graphs. The activation energy was calculated using the Flynn-Wall-Ozawa method. The determined activation energies of the composites were close to each other for each temperature group. In the samples using calcite and vinyltriethoxysilane, relatively higher activation energies were observed in comparison to the samples with boric acid and MAPE.

Abstract Background Guayulins comprise a family of sesquiterpene compounds with potential industrial applications that are extracted from the resinous fraction of the guayule plant (Parthenium argentatum, A. Gray). If a whole industry is to be developed around guayulins, not only their activity should be assessed, but also their stability because the quality of the final products is likely influenced by the time that elapses from harvesting to processing. Thus, the aim of the present study was to evaluate the stability of guayulin compounds from harvested guayule stems or extracted resin after storage at different temperatures to find in which form, stems or resin, is the storage better. Results Results showed that, once extracted, the resin could be stored at 20-25 °C for 3 months or more without significant losses of guayulin content. In the case of harvested stems, however, the findings were more complex, with guayulins A and B degrading over time and guayulins C and D showing enrichment. In addition, analysis of the thermal and thermo-oxidative degradation of the resin and guayulins showed that while guayulins A and B showed a maximum decomposition rate around 280 °C, guayulins C and D decomposed at 245 °C. Such thermal differences might be attributed to the observed oxidation of guayulin A and B standards into guayulin C and D, respectively. Conclusion These findings provide, for the first time, information on the stability of guayulins after harvesting and resin extraction, which could help to the development of an integral industrial process from harvesting to commercializing. Graphical Abstract

The pyrolysis performances and reaction kinetics of pine needles (PN) were investigated by integrating thermogravimetric analysis, Fourier transform infrared spectroscopy, and pyrolysis-gas chromatography/mass spectrometry. The average activation energy of PN was estimated to be 183.2 kJ/mol by Kissinger Akahira Sunose (KAS) and 183.8 kJ/mol by Flynn Wall Ozawa (FWO), respectively at heating rates of 10, 20, and 40 °C/min. The pyrolysis of PN was found to be more efficient at the lower heating rates, while increased heating rates promoted the reaction. Using the King-Kai (K-K) method, the activation energies of hemicellulose, cellulose, and lignin were calculated to be 156, 165, and 172 kJ/mol, respectively. The descending order of evolving gases and functional groups from PN was found to be CO2, C=C, C=O, H2O, CH4, and CO. The main pyrolytic by-products identified were hydrocarbons, phenols, alcohols, ketones, and aldehydes. The determination of kinetic parameters provides fundamental information for predicting the rates at which chemical reactions occur. This study demonstrates the potential of PN as a suitable source for bioenergy.

The present study aims at investigating the effect of hexagonal boron nitride (hBN) nanoplatelets on the properties of acrylonitrile butadiene styrene (ABS) polymer. Composites containing 0-30 vol% hBN were prepared through batchwise melt compounding, which was followed by compression molding. Subsequently, the thermal and thermomechanical properties of the fabricated samples were investigated. The dynamic mechanical analysis (DMA) revealed that the storage modulus of the samples was markedly improved in the entire examined temperature range, while the glass transition temperature also gradually increased as a function of hBN content. According to the thermogravimetric analysis (TGA), the incorporated boron nitride particles enhanced the thermal stability of ABS composites, exhibiting a notably higher decomposition onset temperature. Additionally, the thermal conductivity of the ABS/hBN composites significantly increased by 570% when the hBN content was 30 vol%.

To reduce the lattice oxygen content of Si3N4 green bodies, samples were prepared using an N,N-dimethylacrylamide (DMAA) system. The endothermic and exothermic peaks are related to the decomposition of organic matter and the reaction between pyrolytic carbon and impurity oxides in the sintering process. Multi-step heat preservation during the thermal degreasing process reduced the carbon content and defects. The α→β phase transformation and aspect ratio of grains changed from 89.2% to 4.84:1 at 1640 °C to 96.3% and 7.80:1 at 1700 °C, respectively. The relative density, hardness, fracture toughness, and thermal conductivity of the Si3N4 samples reached 98.5%, 1353 HV, 8.51 MPa·m1/2, and 97.1 W·m−1·K−1, respectively. Pyrolytic carbon can react with SiO2, which reduces the content of the glass phase in the green body and affects the dissolution and precipitation process and lattice oxygen content. In the structure of the Si3N4 sample, carbon particles with sizes of 100–500 nm and near-spherical shapes were observed. Intergranular-phase YMgSi2O5N was formed during the sintering process, which was conducive to improving the thermal conductivity. This article uses lower temperature and no pressure conditions to prepare Si3N4 ceramics, which can provide reference for batch and low-cost production.

The present study compares the kinetics and thermodynamics of the pyrolysis process of coffee and tea waste with respect to their physicochemical properties to analyze their potential as an energy and carbon source. Coffee and tea waste exhibit a promising source as a biofuel that has gross calorific values of 22.7 MJ kg−1 and 20.2 MJ kg−1, with significant differences in the overall volatile conversion of 76 % and 65 %, and as final carbon with a yield of 22 % and 31 %, respectively. Kinetic analyses using isoconversional methods show a trend of activation energy and frequency factor with conversion for both samples, with a significant difference at a conversion beyond 0.6 due to the higher lignin content in coffee waste. The predicted master plots indicate complex pyrolysis kinetics for both samples. Furthermore, the reaction kinetics determined by the multivariate regression approach, assuming parallel independent reactions of the nth order applicable to all heating rates, provide the individual mass change and carbon yield of each reaction process that can be controlled using experimental conditions. Finally, the thermodynamic parameters indicate that the pyrolysis process of both coffee and tea waste is nonspontaneous and endothermic, and its reactivity increases with conversion.

In this study, the combustion behavior of ca-rich oil shale, spruce biomass, and their blends under air and oxyfuel environments of 21/79 % and 30/70 % O2/CO2 like conditions were investigated. Non-isothermal thermogravimetric (TG) experiments coupled with a quadrupole mass spectrometer (MS) were conducted to study individual fuels and their blends at 1:0, 4:1, 3:2, 2:3, 1:4, and 0:1 (0, 20, 40, 60, 80 and 100 wt.% Biomass) under three different heating rates 10, 30 and 50°C/min. Co-combustion synergistic along with the kinetic analysis by the isoconversional Friedman method has been carried out to evaluate the combustion process.The results show that the addition of biomass enhanced combustion performance and reduced burnout temperatures. Under oxy conditions, the ignition temperatures stabilized with a biomass ratio > 40 %. Ash content was reduced with biomass addition and when switching from air to oxyfuel combustion, the temperature of blends’ carbonate decomposition was stable at ∼ 720 °C. A positive synergistic effect in the devolatilization and the combustion of light hydrocarbons occurred at higher biomass ratios. Yet, the char oxidation peaks were below zero indicating a negative effect under 21 % of inlet O2. With increasing the heating rate, the negative synergistic effect was weakened for the three combustion atmospheres. SO2 emissions were reduced with increasing biomass ratio and increased under oxy mode along with H2O release. The activation energy (E) was lower in oxy conditions than in air mode for individual fuel and their blends, compared to the OS sample, the reduction was higher with increasing BM ratios and for the BM fuel. Overall, this study determines the appropriate conditions for the co-combustion of oil shale and spruce biomass under air and oxy modes for future carbon-negative capture applications in industrial oil shale combustion boilers.

To investigate the quantitative relationship between the pyrolysis characteristics and chemical components of tobacco materials, various machine learning methods were used to establish a quantitative analysis model of tobacco. The model relates the thermal weight loss rate to 19 chemical components, and identifies the characteristic temperature intervals of the pyrolysis process that significantly relate to the chemical components. The results showed that: 1) Among various machine learning methods, partial least squares (PLS), support vector regression (SVR) and Gaussian process regression (GPR) demonstrated superior regression performance on thermogravimetric data and chemical components. 2) The PLS model showed the best performance on fitting and prediction effects, and has good generalization ability to predict the 19 chemical components. For most components, the determination coefficients R2 are above 0.85. While the performance of SVR and GPR models was comparable, the R2 for most chemical components were below 0.75. 3) The significant temperature intervals for various chemical components were different, and most of the affected temperature intervals were within 130°C–400°C. The results can provide a reference for the materials selection of cigarette and reveal the possible interactions of various chemical components of tobacco materials in the pyrolysis process.

This study explores the pyrolytic characteristics of coconut shells and nutmeg shells as potential bioenergy sources, addressing a research gap in comparing their energy potential. It employs analytical techniques like Field Emission Scanning Electron Microscopy, Fourier Transform Infrared Analysis, and Thermogravimetric Analysis for surface morphology analysis, volatile compound detection, and pyrolysis process investigation. Using kinetic analysis methods, such as ASTM E2070 - Method A, Friedman, and Vyazovkin, thermodynamic properties like enthalpy, Gibbs free energy, and entropy are determined at a single heating rate. Activation energy, pre-exponential factors, and thermodynamic values are presented for both materials. Coconut shells exhibit higher activation energies, indicating greater thermal stability, especially in ASTM E2070 - A and Friedman methods. In contrast, nutmeg shells have lower activation energies, suggesting simpler decomposition. Thermodynamic evaluations favor coconut shells, highlighting increased disorder during pyrolysis compared to nutmeg shells. These findings offer insights into their thermal degradation kinetics, informing potential applications in pyrolysis processes.