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The synthesized phases with chemical composition $$\left[ {{\text{M}}^{2 + }_{6} {\text{Al}}_{3} \left( {\text{OH}} \right)_{18} } \right]\left[ {{\text{A}}^{ + } \left( {{\text{SO}}_{4} } \right)_{2} } \right]12{\text{H}}_{2} {\text{O}}$$ (M2+ = Mn, Mg, Zn; A+ = Li, Na or K) were evaluated in relation to their thermal behavior by thermogravimetric analysis (TGA), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). In the shigaite (M2+ = Mn), natroglaucocerinite (M2+ = Zn) and motukoreaite (M2+ = Mg) phases, the TGA measurements indicated that all samples were dehydrated up to 200 °C in two steps, followed by dehydroxylation above 300 °C. After the thermal treatment at 1000 °C, formation of oxides/spinels were observed for the shigaite and natroglaucocerinite phases, while for motukoreaite, oxides, spinels and MgSO4 were detected. XRD indicated a reduction in the basal distance from around 11 A for the fully hydrated phases to around 7 A for the dehydrated phases. The thermal treatments of some samples at 100 °C, 150 °C and 200 °C indicated that in all phases, intercalated sulfate and alkaline metal ions can be dehydrated and rehydrated. As indicated by FTIR, at 200 °C sulfate could be grafted to the layers and at 300 °C, for all the phases, a stable mixture of amorphous materials was obtained, which could not be rehydrated.

Ferrous ( $$\hbox {Fe}^{2+}$$ ) and ferric ( $$\hbox {Fe}^{3+}$$ ) iron content in mineral samples was determined from total iron (as obtained, for instance, from X-ray fluorescence analysis) and mass increase upon switching the purge gas from inert to oxidizing, at high temperature, in a thermogravimetric analysis. The method was validated using analytical-grade ilmenite ( $$\hbox {FeTiO}_{3}$$ , or $$\hbox {Fe}^{2+}\hbox {O}\cdot \hbox {TiO}_{2}$$ ) and magnetite ( $$\hbox {Fe}_{3}\hbox {O}_{4}$$ , or Fe2+ · Fe 2 3+ O3). The estimated mass percentages of FeO are less than the expected values, according to chemical composition, by 1.1 and 1.2 percentage points for ilmenite and magnetite, respectively. The application of this method is further illustrated by determining the $$\hbox {Fe}^{2+}$$ and $$\hbox {Fe}^{3+}$$ content, expressed as FeO and $$\hbox {Fe}_{2}\hbox {O}_{3}$$ , in three samples of igneous rocks.

Light (Tlight), middle (Tmiddle) and severe (Tsevere) torrefaction processes by TGA in woody biomass were evaluated in relation to devolatilization rate (Drate), maximum devolatilization rate (DRmax), temperature at the level of 50% weight loss (T50), rate of weight loss at T50 (R50) and weight loss during torrefaction (Wloss-DT). The relationship between these parameters with cellulose, lignin and extractives content was established. The TGA and devolatilization curves showed that DRmax was of 4.16, 1.80 and 0.70%/min for Tlight, Tmiddle and Tsevere respectively. Wloss-DT in Tlight ranges between 3 and 6%, between 9 and 14% in Tmiddle and from 11 to 16% in Tsevere. G. arborea showed the highest Wloss-DT, with 29.10% for Tsevere and C. Lusitania and T. grandis the lowest Wloss-DT, with 15% for Tsevere. The duration of Dmax was of 5 min in Tlight and Tmiddle and 6 min in Tsevere. Cellulose, lignin and carbon presented statistically significant correlations with R50, T50, Wloss-DT and DRmax. Ash content was correlated with Wloss-DT and DRmax in all torrefaction condition. Extractives in dichloromethane was significantly in many parameters. We conclude that the torrefaction of different woody species can be optimized as biomass feedstocks with a specific temperature and time of torrefaction.

The pyrolysis process of both microalgae and sewage sludge was investigated separately, by means of non-isothermal thermogravimetric analysis. The Distributed Activation Energy Model (DAEM) was employed to obtain the pyrolysis kinetic parameters of the samples, i.e. the activation energy Ea and the pre-exponential factor k0. Nine different pyrolysis tests at different constant heating rates were conducted for each sample in a thermogravimetric analyzer (TGA) to obtain accurate values of the pyrolysis kinetic parameters when applying DAEM. The accurate values of the activation energy and the pre-exponential factor that characterize the pyrolysis reaction of Chlorella vulgaris and sewage sludge were reported, together with their associated uncertainties. The activation energy and pre-exponential factor for the C. vulgaris vary between 150–250 kJ/mol and 1010–1015 s−1 respectively, whereas values ranging from 200 to 400 kJ/mol were obtained for the sewage sludge activation energy, and from 1015 to 1025 s−1 for its pre-exponential factor. These values of Ea and k0 were employed to estimate the evolution of the reacted fraction with temperature during the pyrolysis of the samples under exponential and parabolic temperature increases, more typical for the pyrolysis reaction of fuel particles in industrial reactors. The estimations of the relation between the reacted fraction and the temperature for exponential and parabolic temperature increases were found to be in good agreement with the experimental values measured in the TGA for both the microalgae and the sludge samples. Therefore, the values reported in this work for the activation energy and the pre-exponential factor of the C. vulgaris can be employed as reference values in numerical studies of the pyrolysis process of this biofuel since its chemical composition is quite homogeneous. In the case of sewage sludge, due to the heterogeneity of its composition, the results reported for the kinetic parameters of the pyrolysis process can be employed to describe the pyrolysis of sludge with similar composition. The authors express their gratitude to the BIOLAB experimental facility and to the “Programa de movilidad de investigadores en centros de investigación extranjeros (Modalidad A)” from the Carlos III University of Madrid (Spain) for the financial support conceded to Antonio Soria for a research stay at the German Aerospace Center DLR (Stuttgart, Germany) during the summer of 2016. The authors also gratefully acknowledge the financial support provided by Fundación Iberdrola under the “VI Programa de Ayudas a la Investigación en Energía y Medioambiente”. Funding by the energy, combustion, and gas turbine technology program (EVG) of Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR), the German Aerospace Center, is gratefully acknowledged as well as funding by the DLR international collaboration project “Accurate Kinetic Data of Biomass Pyrolysis” Publicado

In this study, the relationship between wood cellulose crystallinity, influence of extractives on wood degradation, correlation between chemical composi- tion, and physical properties of four wood species were investigated by chemical analysis, Fourier transform infra- red (FTIR) spectroscopy, and thermogravimetry. The chemical analysis showed that Dipteryx odorata and Mezi- laurus itauba (ITA) contained a higher quantity of extrac- tives and lower quantities of holocellulose and lignin than Eucalyptus grandis (EUG) and Pinus elliottii. FTIR spectros- copy indicated that higher extractives content in ITA might be associated with more intense bands at 2920, 2850, and 1510 cm � 1 . The lower values for hydrogen bond energy and hydrogen bond intensity showed that EUG contained more absorbed water than the other species. Thermogravimetry confirm that lower extractive contents leads to a better wood thermal stability. This study showed that through the methods used previous informa- tion about structure and properties of wood can be obtained before use it in composite formulations. V C 2012

Macroalgae are often referred as seaweed and could be significant biomass resource for the production of numerous energy carriers including biofuels. In this study, the chemical composition of Gracilaria changii (G. changii) and Gelidium pusillum (G. pusillum) were determined through proximate and ultimate analysis and the thermal degradation behaviour of G. changii and G. pusillum were investigated via thermogravimetric analysis (TGA) in determining the important main composition to be considered as biomass fuels. It has found the pyrolysis of G. changii and G. pusillum consists of three stages and stage II is the main decomposition stage with major mass loss of around 52.16% and 44.42%, respectively. The TGA data were then used for determination of kinetic parameters of the pyrolysis process using three model-free methods: Kissinger, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO). The apparent activation energy calculated by using Kissinger method for G. changii was lower than G. Pusillum, i.e.173.12 kJ/mol and 193.22 kJ/mol, respectively. The activation energies calculated from KAS and FWO methods were increased with increasing the pyrolysis conversion with average activation energies of 172.32 kJ/mol and 181.19 kJ/mol for G. changii while for G. pusillum (177.42 kJ/mol and 187.4 kJ/mol). G. pusillum has lower and wider distribution of activation energy and revealed that the pyrolysis process for G. changii was easier than G. pusillum. These data provide information for further application for designing and modelling in thermochemical conversion system of macroalgae biomass.

Pyrolysis and CO2-gasification behavior of lignites representing four different deposits in Turkey were investigated by Thermogravimetric Analysis (TGA) in the temperature range from 750 °C to 1000 °C. The rates of pyrolysis and CO2-gasification were evaluated from the corresponding TGA profiles. As expected, maximum pyrolysis rates for each coal were shown to be constant with respect to the final carbonization temperature. Lignites used in this study are from the tertiary period, chosen from major coal deposits in Turkey and their carbon contents are in the range of 60–70% (daf) based on ultimate analysis. They have shown different gasification reactivities under similar conditions and the reactivity sequence was found to be temperature dependent. In an attempt to correlate the maximum reactivities with textural properties of coals; BET (N2) and Dubinin–Radushkevich (CO2) areas of original coals, chars and gasification products were determined. To assess the catalytic effect of mineral constituents on gasification, chemical composition of ashes were also analyzed. Enhanced reactivity of one particular lignite at a relatively high temperature (1000 °C) was attributed to favorable distribution of micropores and feeder pores evolved during gasification and its relatively high iron content which has been known to be one of the species which can catalyze gasification reaction at the prevailing temperature. Apparent activation energies were evaluated using the Arrhenius plots of the maximum reactivities and the values were found to be in the range of 29.0–124.8 kJ/mol.

The hygroscopicity of mineral aerosol samples has been examined by three independent methods: diffuse reflectance infrared Fourier transform spectroscopy, thermogravimetric analysis and differential mobility analysis. All three methods allow an evaluation of the water coverage of two samples, CaCO3 and Arizona Test dust, as a function of relative humidity. For the first time, a correlation between absolute gravimetric measurements and the other two (indirect) methods has been established. Water uptake isotherms were reliably determined for both solids which at 298 K and 80% relative humidity exhibited similar coverages of ~4 monolayers. However, the behaviour at low relative humidity was markedly different in the two cases, with Arizona Test Dust showing a substantially higher affinity for water in the contact layer. This is understandable in terms of the chemical composition of these two materials. The mobility analysis results are in good accord with field observations and with our own spectroscopic and gravimetric measurements. These findings are of value for an understanding of atmospheric chemical processes.

A study was conducted to compare the physical properties of Aqueous Cream BP obtained from different manufacturers. The samples were studied using thermogravimetric analysis (TGA) and stress scan rheology as complimentary techniques. TGA studies showed two main peaks in the first derivative curves, corresponding to free and lamellar water. The profiles for creams obtained from different manufacturers showed marked variations between the samples, although the total water content was similar in all cases. Similarly, stress scans also showed marked differences between the creams, although no clear correlation between the thermogravimetric and rheological data was observed under the conditions used in the study. Three batches of cream from one manufacturer were then examined. Differences in the rheological properties were again observed, but less marked differences were seen in the TGA profiles. The study indicates that while the chemical composition of commercial aqueous cream may be controlled, considerable variations in the physical properties of these systems may be observed, both between different manufacturers and between batches from the same manufacturer. The implications of the poor correlation between stress scan rheological and thermogravimetric analysis data are discussed in terms of the use of these two methods in the quality control of creams.

Alternative biomass makes up a considerable portion of the waste from biomass processing in forestry and agriculture. The aim of this work was to create pellets from several sources of alternative biomass, e.g., lawn clippings, corn husks, linden leaves, and pine needles, which were compared to pure wood pellets. Analysis of the fuel properties focused on their chemical composition, thermogravimetric analysis, calorific values, and ash melting temperatures. The power and emission parameters of the fuels were determined via an automatic pellet boiler. The primary issues in the combustion of the alternative biomass types were low calorific values, increased emissions, high ash contents, and low ash melting temperatures. The two primary options for solving these problems are the production of fuel mixtures with wood or the use of new combustion technologies. This work also dealt with the combustion of alternative biomass via a rotary burner. The results showed an increase in the ash content of the alternative biomass, which also led to the burner occasionally going out due to clogging with the accumulation of ash and sintering. Based on the results, only pellets from pine needles and corn husks can be recommended for further use.

The thermogravimetric properties and chemical characterization of rice straw (RS) pretreated by mixed culture of white-rot fungi Phanerochaete chrysosporium (P. chrysosporium) and brown-rot fungi Gloeophyllum trabeum (G. trabeum) were investigated. The mixed fungal pretreatment showed a synergistic effect, which resulted in an energy-efficient pyrolysis of pretreated rice straw. The differences in thermochemical conversion of rice straw before and after fungal pretreatment were investigated using thermogravimetric analysis and the Flynn–Wall–Ozawa (FWO) method. Furthermore, the pretreated samples were also analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) to illuminate the changes in chemical composition and pyrolysis behavior. Compared to single fungal pretreatment, the mixed fungal pretreatment worked better and exhibited great potential in biomass pyrolysis.

This study aims to investigate the co-liquefaction of high-density polyethylene (PE) and low density polyethylene bags (PB) with sugarcane bagasse (SCB) in supercritical ethanol solvent. The effect of blending ratios of SCB/PB and SCB/PE is studied. Results indicate that blending ratio of low density plastic bags and high-density polyethylene impacts the product distribution during solvo-thermal process. The optimum conversion of SCB/PE and SCB/PB up to 57.3% and 59.4% with bio-oil yields of 31.5% and 30.3% respectively are obtained at 280 °C. The higher heating values (HHV) of bio-oil obtained from SCB/PE and SCB/PB are 34.9 and 34.8 MJ/kg, respectively. CHNS/O, chemical composition, carbon and proton NMR, Thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) analyses of bio-oil have been conducted. Investigation suggests that the SCB/PE and SCB/PB derived bio-oil have the superior qualitative properties compared to pure sugarcane bagasse.

This study investigated the effect of lipid extraction of microalgae feedstocks subjected to hydrothermal carbonization (HTC) with regard to the carbonization degree, chemical composition and phytotoxicity of hydrochars produced under different reaction temperatures and residence times. Special attention was given to the formation and composition of secondary char, as this part of the hydrochar may be of particular importance for environmental and technical applications. A microalgae polyculture grown in municipal wastewater was extracted to retrieve lipids, and both unextracted (MA) and extracted microalgae (EMA) were used to produce hydrochars at 180–240 °C for 1–4 h. The composition of the hydrochars was thoroughly characterized by elemental analysis, thermogravimetric analysis and pyrolysis–gas chromatography/mass spectrometry analysis. MA exhibited a greater carbonization degree than EMA and contained higher amounts of secondary char under the same processing conditions. During the carbonization of EMA, more decomposition products remained in the liquid phase and less polymerization occurred than for MA, which explained the lower solid yield of EMA-derived hydrochars in comparison to MA hydrochars. Consequently, although they contained potentially toxic substances (i.e., carboxylic acids, aldehydes and ketones), the EMA-derived hydrochars exhibited a lower phytotoxic potential. This indicates that low-temperature hydrochars containing less than 10% of extractives might be suitable as soil amendments, whereas extractive-rich hydrochars would be more appropriate for other long-term applications, such as adsorbents for contaminant removal, energy storage and composite materials. Detailed characterization of microalgae-derived hydrochars is required to enable the most suitable application areas to be identified for these materials, and thereby make full use of their function as carbon sinks.

Pyrolysis kinetics of Quercus cerris cork was investigated using thermogravimetric analysis with heating rates of 10, 20, 50, and 100 °C min−1. The activation energies and chemical compositions of cork components were determined by different model-fitting methods, isoconversional Kissinger-Akahira-Sunose (KAS) method, and Lorentzian multi-peak fitting. Wet chemical analysis of cork was conducted to compare with the chemical compositions predicted by the kinetic models and Lorentzian multi-peak fitting. The results show that pyrolysis of Quercus cerris cork possibly follows nth-order kinetics, and best fits to the experimental data were obtained by three-halves kinetics followed by first-order and contracting sphere models. The fit qualities of the different models were close implying that the first order models could be used for practical applications. Six pseudo-components approximation used in these models suggested that while cork hemicelluloses and cellulose undergo thermal decompositions similar as in wood, cork suberin decomposes in two distinct steps, i.e., cellulose-like and lignin-like decompositions. Isoconversional KAS method showed that the average activation energy of Quercus cerris cork is approximately 298 kJ mol−1. The reconstructed mass loss curves after Lorentzian multi-peak fitting resulted in smaller activation energies for cork components.

This study aims to explore the potential of the NaOH-treated Cytostachys renda fibre to be reinforced in the polymeric composites. The NaOH concentrations were prepared as 1, 3, and 5 wt% for soaking time of 1 and 2 h. The treated fibres were characterized in terms of density, chemical composition, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), and Thermogravimetric analysis (TGA). The results revealed that the density is improved with an increase in the concentration and soaking time. NaOH treatment has reduced the amorphous hemicellulose and lignin content. On the other hand, the improved crystallinity index by 6% was observed for fibre treated at 3% NaOH for 1 h, along with the enhancement of cellulose content as much as 0.27%. From the FTIR analysis, it was observed that the presence of C H stretching vibration from the ether in the treated fibre for 1 h soaking time would form a strong interaction with the polymeric matrix. The TGA results showed that fibre treated at 3% NaOH for 1 h exhibited the highest thermal stability compared to the untreated and other treated fibres. Therefore, it can be concluded that the fibre treated with 3% of NaOH for 1 h soaking time could act as a potential reinforcement in the polymeric composites for light weight applications.

Hydrothermal liquefaction (HTL) is a promising technology that can produce biocrude oil from wet biomass. The biocrudes, while generally acknowledged to be more stable than pyrolysis oils, are still thought to degrade relatively quickly, which limits their applicability. In this investigation, the storage stability of biocrude produced from hydrothermal liquefaction of microalgae was systematically studied over 60 days, and the effect of the storage material, feedstock species, liquefaction temperature and storage temperature were assessed. Biocrudes obtained at 300 °C and 350 °C from the microalgae Spirulina and Chlorella vulgaris were stored at three temperatures: cold (4 °C), ambient (20 °C) and elevated temperatures (35 °C), over the two-month period. The dynamic viscosity, higher heating value, thermogravimetric analysis and elemental and chemical composition were assessed. The viscosity of the biocrudes only increased considerably at 35 °C. The reaction temperature and biomass type were also strong determining factors of the impact on biocrude stability. Biocrudes produced from C. vulgaris were more stable than the Spirulina, and the crudes formed at 350 °C were considerably less reactive than those produced at 300 °C. This demonstrates that biocrudes can be stored without substantial degradation, allowing a more flexible approach to upgrading to value products.

Carbonated hydroxyapatite (C-HAp) is one of the most attractive biomaterials for bone tissue engineering due to its compositional and biological similarity to the mineral part of human bone. In the present work, we have used a two-step fabrication process to precipitate a poorly crystalline Carbonated Hydroxyapatite (C-HAp) with nano-size particles at room temperature (20 °C) through the dissolution-precipitation process. For the first time, stoichiometric hydroxyapatite (S-HAp) was used as a precursor. The obtained C-HAp was evaluated for its structure; chemical composition and particle size using numerous analytical tools, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), Thermogravimetric analysis (TGA), and Scanning Electron Microscopy (SEM). The chemical composition, carbonate content, and molar ratio (Ca/P) of the C-HAp phase was investigated by the corresponding X-ray energy dispersive spectrometer (EDX). Therefore, the dissolution-precipitation reaction was confirmed to be useful to transform S-HAp to C-HAp.

In just over half a century electronic equipment and products have revolutionized human lifestyle. At the product’s end of life, e-waste, its components material and other materials have influenced and infiltrated environment in every part of globe. The hazardous effect of plastic materials and debris to biodiversity is well established, but mitigation and planning are often hampered by lack of quantitative data on waste accumulation patterns in landfill. Here we document a study on the pyrolysis of non-metallic material of printed circuit board, the basic elemental part of electronic waste. The non-metallic material is separated from printed circuit board waste during the copper separation processes and was found in powder form at average size up to 177 μm. The purpose of this study is to experimentally investigate the pyrolysis behavior of the non metallic material of printed circuit boards (PCB) waste fraction at a temperature range of 300 ◦C to 600 ◦C by means of the Thermogravimetric Analysis (TGA) and seek to find out the effective pyrolysis temperature that could be used in pyrolysis process in production scale. The experimental results reveal that the chemical composition of the PCB reflects that the main decomposition of PCBs occurs between 250 ◦C and 450 ◦C, and effectively decomposed at 403 ◦C. The pyrolysis of PCBs showed a varying production of aromatic compounds such as phenol, bromophenol, styrene, methylstyrene, and bisphenol A as well as non-aromatic compounds such as acetone and bromomethane, which are strongly related with the initial chemical composition of PCBs.

The objective of this study is to determine the catalytic potential and adsorption characteristics of coal bottom ash (CBA) for utilization in biomass gasification for cleaner fuel production. The analysis shows the presence of metals such as Fe, Al, Ca, and Mg in CBA that have been used as common elements of catalysts in gasification. The surface of CBA is porous and consists of irregular shape particles and crystalline structure determined using characterization techniques. The surface area (51.02 m2/g), pore volume (0.1 cm3/g), and pore width (3.03 nm) of CBA were determined using Brunauer–Emmett–Teller analysis. The reactivity of CBA in a CO2 environment at 500, 600, 700, and 800 °C is measured through thermogravimetric analysis, and variation in chemical composition of all metal oxides and CaO is measured after CO2 treatment. The CBA adsorbs about 1.15 and 1.51 wt % of CO2 at 25 and 60 °C in high-pressure volume adsorption tests. The highest weight loss of about 14% occurs at a heating rate of 10 °C/...

In the present study, a lignocellulosic from inedible fruits of Caesalpinia ferrea (CFIF) — a tree mainly found in Brazil and Bolivia — was studied as potential biomass for production of biochar under different pyrolysis temperatures. The characterization of the biochars were done using different techniques: chemical composition, elemental analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), small-angle X-ray scattering (SAXS), and scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS). The chemical composition showed a higher amount of lignin, extractives, moisture, and hemicellulose than the most common fibers in literature. The considerable presence of the aforementioned components contributed to the low thermal stability observed in TGA. As a result, the complexes formed are initially less ordered and become more ordered at higher temperatures. The elemental analysis showed that the carbon content increased with pyrolysis temperature while the nitrogen and hydrogen followed the opposite trend, influencing the final biochar elements, also confirmed by SEM/EDS. CFIF have potential for the production of biochar using isothermal and non-isothermal processes based on the selection of appropriate conditions.

The essential oil (EO) of pink pepper has important biological properties that can enhance its application in the pharmaceutical, cosmetic and food industries. The objective of this study was to characterize the EO of pink pepper seeds in terms of their chemical composition and thermophysical properties. Certified pink pepper seeds obtained commercially were used. The EO was extracted by hydrodistillation and chemically characterized in a gas chromatograph coupled to mass spectrometer (GC/MS). The thermoanalytical characterization was performed on a simultaneous high resolution equipment, and the Thermogravimetric Analysis (TG) and Differential Scanning Calorimetry (DSC) were used to determine the physical-chemical and kinetic properties of the OE in the room temperature range up to 250 ºC in the 20 ºC.min-1 ratio under nitrogen atmosphere. The Arrhenius kinetic model was applied to determine the activation energy of the EO. A total of 51 chemical compounds were detected in the pink pepper EO, of which 42 compounds were identified (54.7% of monoterpene compounds and 45.3% sesquiterpenes). The major components were ?-pinene (26.80%), germacrene D (11.25%), sabinene (11.13%) and terpinen-4-ol (8.59%). The thermogravimetric analysis indicated a single stage of thermo-degradation of the pink pepper EO between 74.8 ºC and 184.7 ºC, being an endothermic peak in the physical transition of vaporization. The variation of enthalpy and activation energy of EO were found with values of = - (39.8 ± 9.5) KJ.Kg-1 and = - (2,546 ± 0.033) KJ.mol-1, respectively. The data presented in the thermogravimetric analysis of pink pepper seeds EO allowed observing important thermal parameters for the definition of industrial processes that can use it as raw material, so that its biological activities can remain stable under controlled temperature conditions and below the range degradation.

The development of sustainable extraction methods to obtain natural products constitutes a challenge for the food industry. The aim of this work was to compare yield, separation efficiency, chemical composition, and physicochemical properties of the mucilage extracted from fresh cladodes (FNM) and mucilage extracted from dehydrated cladodes (DNM) of O. ficus indica. Suspensions of fresh and dehydrated cladodes (4% w/w) were prepared for mucilage extraction by using a mechanical separation process. Subsequently, the separated mucilage was precipitated with ethyl alcohol (1:2 v/v) then, yield and separation efficiency were determined. The mucilage was characterized by measuring Z potential, viscosity, color, and texture attributes. Additionally, chemical proximate analysis, scanning electron microscopy, and thermogravimetric analysis (TGA) were conducted. No significant differences (p &lt, 0.05) were detected in the yield and separation efficiencies between samples. Nevertheless, the dehydration process of cladodes prior to mucilage extraction increased protein, ashes, nitrogen free extract, and calcium content. The viscosity was higher in DNM than in FNM. The TGA revealed a different thermal behavior between samples. In addition, the DNM showed lower L (darkness/lightness), cohesiveness, adhesiveness, and springiness values than those of FNM. These results support that differences found between the chemical and physicochemical properties of DNM and those of FNM will determine the applications of the mucilage obtained from the O. ficus indica cladodes in the food, pharmaceutical, and cosmetic industries.

Crystalline rare-earth (RE) carbonates having large particle size were prepared from the lixivium of weathered crust elution-deposited rare-earth ores using the precipitation method with ammonium bicarbonate as the precipitant. Their chemical composition was studied using elemental and thermogravimetric analyses (TGA), and their structure and morphology were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results demonstrate that the crystalline rare-earth carbonate is a hydrated basic carbonate or oxycarbonate and not astable intermediate carbonate in the process of thermal decomposition. The particle size of crystalline rare-earth carbonates with large particle size is in the range of 50–200 µm. With an RE2O3 content of up to 95wt%, the quality of crystalline rare-earth carbonates is higher compared to the Chinese National Standard (GB/T 28882-2012). The quality of the product is superior to the Chinese National Standard.

Thermal treatments have the effect of reducing the hygroscopicity and improving the resistance to microbiological attack of wood by the degradation of its chemical constituents. During the treatments, the mass of the wood is reduced, a factor that can affect the quality of the materials according to their use. The objective was to verify the effect of the thermal treatment variables on the thermogravimetric properties and the chemical composition of Eucalyptus grandis. The treatments were carried out in a vacuum oven with three atmosphere conditions - vacuum; N2; vacuum+N2 at temperatures of 140, 180 and 220 °C for 6 hours. It was observed that the mass loss during treatments differed only according to the temperatures used. The extractive content, total lignin and holocellulose presented significant changes only at 220°C in all three atmospheres. In the thermogravimetric analysis, the greatest value of residual mass was found in the treatment that used nitrogen and 220 °C, thus demonstrating that this treatment was more invasive, leading to the conclusion that the vacuum application can help to reduce the degradation of the constituents of the eucalypt wood. Wood, which can lead to the production of thermally treated wood without great losses in the mechanical properties.

Typical five MSW components (paperboard, PVC, sawdust, cotton fabric, and vegetables) were examined by using Py-GC/MS and TG-FTIR. Py-GC/MS experimental results showed different products at 500 °C with varying percentage including benzene derivatives, phenolic compounds, acids, alcohols, aldehydes and ketones, alkanes, and other compounds and revealed that the pyrolyzed organic content in different components varied by the temperature gradient. During rapid pyrolysis of PVC at 600–800 °C, the yield of major plasticized pyrolysis products including benzene and toluene was significantly increased from 21.76 wt% to 39.45 wt% and 15.03 wt% to 22.33 wt%, respectively. The thermogravimetric analysis also revealed the degradation and significant conversion of components at higher temperatures. Furthermore, to have a better understanding, mixed waste pyrolysis results were also compared with the calculated mixed waste results. The results disclosed the strong interactions between the PVC pipe and vegetables. In addition, the binary mixture of PVC with other components also promoted low-temperature pyrolysis. Besides, paperboard also showed strong interaction with sawdust and cotton clothes. TG-FTIR results disclosed that when the chemical composition and constituents of waste components are similar, the composition becomes the main influencing factor for mixed pyrolysis. In addition, a kinetic approach was also employed to determine the activation energy of MSW components during pyrolysis and the activation energy of the pyrolysis of vegetables was found to be in lower range with 82.85 E/(kJ·mol−1) in comparison with other components.

Four bituminous coals and one anthracite were used in this study. On the basis of the similar volatile matter contents of the four bituminous coals, the effects of ash in coal on the microstructure, carbonaceous structure, and chemical composition of pulverized coal were studied. Thermogravimetric analysis was used to study the effect of the addition of anthracite on the combustibility of four different bituminous coals. The results showed that with the increase of ash content in pulverized coal, the microstructure of carbon particles in coal was not much different. However, the analysis results of Raman spectroscopy and X-ray diffraction pattern showed that as the ash content increased, the degree of graphitization of coal carbonaceous structure gradually decreased. The combustibility of the four bituminous coals were better than that of the anthracite. When bituminous coal and anthracite were mixed and burned, the combustibility of the mixed sample decreased as the ash content increased.

In this study, feed coal (FC) from the Figueira Thermoelectric Power Plant (FTPP), located in the state of Paraná (PR), Brazil was characterized by X-ray fluorescence (XRF), X-ray diffractometry (XRD), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), particle size distribution analysis by laser diffraction, loss of ignition (LOI), total carbon content (TC), pH and conductivity. FC-derived by-products (CCBs) collected at the FTPP were: bottom ash (BA), fly ash from cyclone filter (CA) and fly ash from bag filter (FA). In addition to the techniques used for feed coal characterization, CCBs were also characterized by total surface area (by using BET method), external surface area (by using laser diffraction), cation exchange capacity (CEC), bulk density, besides leaching and solubilization tests. FC sample contains 72.2% of volatile material, of which 55.3% is total carbon content. LOI, FTIR, TGA and TC analyzes corroborated with these results. The main crystalline phases in the FC sample were found to be quartz, kaolinite and pyrite. The elements As, Cr, Ni and Pb were encountered in the FC sample, indicating that the use of FTPP feed coal should be monitored due to the toxic potential of these elements. The three coal ashes were classified as class F according to ASTM and presented similar chemical composition, with total content of the main oxides (SiO2, Al2O3 and Fe2O3) above 72%. Ashes enrichment factor analysis (EF) showed that As, Zn and Pb concentrate mainly in fly ash from bag filter (FA), whereas the elements K and Mg presented higher enrichment in the bottom ash (BA) . All ashes presented quartz, mullite and magnetite as crystalline phases, as well as the same functional groups, related to the presence of humidity, organic matter and Si and Al compounds. XRD, XRF, TGA, FTIR, LOI and TC techniques were correlated and confirmed the obtained results. Total and external surface area values of CCBs were related to the total carbon content (TC), as well as to the results of particle size distribution and the scanning electron micrographs of the samples. On the other hand the CEC of the ashes showed relation with the particle size distribution and with the external surface area. Leaching and solubilization tests of CCBs showed that FA sample was considered hazardous and classified as class I waste, while CA and BA samples were considered non-hazardous and non-inert wastes and classified as class II-A. FA sample from Figueira power plant must be discarded only after treatment or a stringent disposal criterion must be followed to avoid contamination on site. In this work, feed coal sample was also compared to the CCBs samples generated from it. The results showed the differences between fuel and products through the different characterization techniques. In addition to contributing to the understanding of the relationship between coal and its combustion products, this work can also help to reduce the environmental impacts caused by the CCBs disposal, as well as can also be used to compare the characteristics of CCBs from FTPP with the new wastes that will be generated by the same thermal power plant that will be soon modernized.

Co-pyrolysis and CO2 co-gasification of paper and polystyrene blends in different mixture ratios were studied at 1173 K using a laboratory scale tube reactor and thermogravimetric analysis. The chemical composition and yield of the syngas produced was analyzed by a micro gas chromatograph to understand the influence of mixture components. Co-pyrolysis positively impacted the syngas yield exhibiting a synergistic influence on cracking reactions leading to increased gaseous yield having almost double the amounts of hydrogen yield. Co-gasification using CO2 increased the total gas yield with enhanced synergistic conversion. This effect provided a non-linear impact on the combustible gases in the gaseous yields when compared to the separate gasification of these feedstocks. The synergistic enhancement of co-pyrolysis conversion in paper-polystyrene led to lower char present for CO2 to react during CO2 co-gasification that lead to lower CO during the gasification of this blended char residue. The mixtures of paper with polystyrene provided increased product gas yields and enhanced conversion with an increase in polystyrene content. The results showed the effectiveness of producing high energy density syngas from co-gasification which can alleviate material handling issues present in segregation of waste, such as plastics and biomass providing uniform valuable product from diverse waste feedstocks with minimal need for classification.

In the present study, the performance of bis(trifluoromethylsulfonyl)amine lithium (LiTFSI) and lithium tetrafluoroborate (LiBF4) salts as a novel lubricant additive was assessed. The oxidative stability of ester based lube oil (L2) when mixed with LiTFSI and LiBF4 (1.0 and 5.0 mass%) was estimated by calorimetric techniques combined with the thermokinetic model. A significant improvement in the viscosity index by 8.0% was observed when 5.0 mass% LiTFSI was used. Thermogravimetric analysis revealed two major mass loss steps between 98.0 and 336.0 °C and 292.0 to 454.0 °C at different heating rates. The chemical composition of treated samples revealed the formation of octatriacontyl pentafluoropropionate complex, which could be responsible for the increase in thermal stability of L2. The estimated average value of apparent activation energy (Ea) of L2 was 82.5 kJ·mol−1. The 5.0 mass% LiTFSI sample had the highest oxidative stability, and the kinetic models revealed that the Ea was 121.1 kJ·mol−1. The thermal performance of lubricant oil could be improved by increasing the concentration of Li salt additives up to 5.0 mass%.

This study compared the chemical composition, microstructural, and mechanical properties of human and bovine dentin subjected to a demineralization/remineralization process. Human and bovine incisors were sectioned to obtain 120 coronal dentin beams (6 × 1 × 1 mm3) that were randomly allocated into 4 subgroups (n = 15) according to the time of treatment (sound, pH-cycling for 3, 7, and 14 days). Three-point bending mechanical test, attenuated total reflectance–Fourier transform infrared (ATR-FTIR), thermogravimetric (TG), and X-ray diffraction (XRD) techniques were employed to characterize the dentin samples. Regarding chemical composition at the molecular level, bovine sound dentin showed significantly lower values in organic and inorganic content (collagen cross-linking, CO3/amide I, and CO3/PO4; p = 0.002, p = 0.026, and p = 0.002, respectively) compared to humans. Employing XRD analyses, a higher mineral crystallinity in human dentin than in bovines at 7 and 14 days (p = 0.003 and p = 0.009, respectively) was observed. At the end of the pH-cycling, CI (ATR-FTIR) and CO3/PO4 ratios (ATR-FTIR) increased, while CO3/amide I (ATR-FTIR), PO4/amide I (ATR-FTIR), and %mineral (TG) ratios decreased. The extension by compression values increased over exposure time with significant differences between dentin types (p

The physicochemical properties of slag are of great importance in pyrometallurgy. If there is a volatile component in the slag, evaporation will inevitably occur. As a result, the slag composition will change, and the measured results will be inconsistent with the original slag composition. Therefore, the traditional methods can be applied to determine the properties of slag, however, the change in slag composition will lead to the inaccuracy of the results. Two typical kinds of slag ESR slag with higher CaF2 and Pb smelting reduction slag with higher PbO were chosen, and melting point measurements were taken as an example to demonstrate the new method in practice. Weight loss measurements and evaporation test with thermogravimetric (TG) analysis, as well as high-temperature mass spectrometer (MS) tests were carried out to identify the volatiles. It was found that CaF2 and MgF2 is the main volatiles with a small amount of AlF3 to ESR slag and PbO is the main volatile with a small amount of ZnO. Based on these points and the weight loss, the slag melting points measured with traditional method and the slag chemical composition were modified to fit the melting point value. This way is proved to be feasible in theory and practice. Some suggestion for further research are proposed. The work will be of significance for both slag and molten salt with volatiles.

The impact of low-pressure treatment on the crystal structure, morphology, and chemical composition of ettringite, due to their major importance with respect to processability (i.a., drying conditions) and to the analysis of ettringite-containing samples, is examined utilizing X-ray diffraction, thermogravimetric analysis, Raman spectroscopy, and environmental scanning electron microscopy. Synthetic ettringite was treated for various durations (5 min up to 72 h) and at two different levels of low-pressure (4.0 mbar and 60 µbar). Evaluation showed a correlation between the procedural parameters (time and pressure), the chemical composition, and the morphology of ettringite. The experiments reveal that, when exposed to 4 mbar pressure, nearly no changes occur in the ettringite’s morphology, whereas the crystals undergo swelling and slight deformations at very low pressures (60 µbar and 35.3 nbar), which is attributed to the loss of bound water and the partial transformation from ettringite to quicklime, anhydrite, and calcium aluminate. Furthermore, the strongly dehydrated ettringite shows the same morphology.

This paper describes the effect of calcination temperature on the phase composition, chemical composition, and morphology of ZrO2 and Al2O3 powders modified with 3-aminopropyltriethoxysilane (APTES). Both ceramic powders were modified by etching in piranha solution, neutralization in ammonia water, reaction with APTES, ultrasonication, and finally calcination at 250, 350, or 450 °C. The obtained modified powders were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, particle size distribution (PSD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS), and thermogravimetric analysis (TGA).

Dynamic thermogravimetric analysis is applied to investigate the thermal devolatilization of dry distiller’s grain with solubles (DDGS), the major by-product of bioethanol plants. Compared with lignocellulosic biomass, the DDGS devolatilization occurs over a much wider temperature range and with slower rates. This reveals complex dynamics attributable to a peculiar chemical composition comprising, in addition to lignocellulose, proteins, starch and other minor components. The evolution of lumped volatile product classes is well described by a five-step reaction mechanism. The numerical solution of the ordinary differential equations together with a minimization of the objective function leads to activation energies invariant with the heating rate. The estimated values of 89, 120, 158, 102 and 113 kJ/mol are, on average, higher than those obtained under oxidative environments but still lower than those typically estimated for wood.

The most important challenge in solid feedstock thermal conversion methods is minimising CO2 emissions. In this work, the gasification of pine sawdust in a mixture of N2 and CO2 was investigated for the reduction of CO2 by a calcium oxide loop. The experiments were conducted at 600, 700, and 800 °C in a fixed-bed reactor. The biomass was mixed with the calcium oxide at a ratio of 1:1. The chemical composition of the syngas was analysed using gas chromatography. Moreover, the high heating values of the received gas samples were calculated, and thermogravimetric analysis and Fourier-transform infrared spectroscopy analysis were performed to investigate the absorption of CO2 by CaO. The results of the gasification process showed that the syngas contained CO, CH4, CO2, H2, N2, and other low hydrocarbons. The most significant results were obtained for a 2:1 ratio of N2 to CO2 at 700 °C, and a CO2 reduction of 25% was observed. Moreover, the catalytic properties of CaO increased the concentration of H2 in the produced syngas by up to 10%. A temperature of 800 °C was too high for the carbonation reaction of CaO. This study presents a possible solution for achieving negative carbon emissions.

The goal of our current research on Shivee Ovoo coal was to characterise the initial coal as well as its hard and liquid products after pyrolysis. To begin with, proximal and ultimate analyses of Shivee Ovoo coal have revealed that it is an oxidised brown coal of the lignite type with the B2 mark. The thermal degradation process of Shivee Ovoo coal was investigated using a thermogravimetric analyzer, which for the first time determined the thermal stability of the coal sample by determining thermal indices from the TG curve, such as T5% -71.85°C; T15% -321.18 °C; T25% -490.64°C from the TG curve, which are the characteristics of lower thermal stability. The yields of produced hard, liquid, and gas products were determined by pyrolysis of Shivee Ovoo coal at various heating temperatures. The most suitable heating temperature was 500°C, which resulted in a higher yield of condensed liquid product -6.28 percent (tar). The yield of all liquid (tar and pyrolysis water) and gas products (44%) indicates that the coal organic material underwent intense thermal decompositions with a greater degree of conversion. This confirms the previously stated and determined reduced thermal stability characteristics of Shivee-Ovoo coal, indicating that it is better suited for gasification and liquefaction. In addition, the yield of hard product (semi-coke) is 56.48 percent at 500oC, which is an important product of the pyrolysis of Shivee Ovoo coal, and its proximate analysis results show that the volatile matter content decreased three times and the caloric value increased by 1000 kcal/kg when compared to the initial coal sample, indicating that it can be used as a smokeless fuel. The chemical composition of pyrolysis tar in group organic compounds obtained by chemical analysis shows that the tar consists largely of neutral oils (81.9%), asphalteines (13.6%), free carbons (3.93%), and organic bases, organic acids, and phenolic compounds (less than 1.0%). The tar was also distilled at room temperature, yielding several fractions with varying boiling temperatures, including a yellow colored light fraction -15.93% (18-180°C), a brown colored middle fraction -15.44% (180 -330°C) and ablack colored heavy fraction -44.53% (330°C>). In compared to the initial coal sample, scanning electron microscopes (SEM) images of generated activated carbon from pyrolyzed hard residue are different.The original coal sample's SEM picture shows compact solid pieces. In comparison to the initial coal sample, the SEM image of carbonised and activated coal sample shows a porosity structure with meso and macro pores. GC/MS analysis was used to investigate the solubility and chemical composition of neutral oil isolated from Shivee Ovoo coal pyrolysis tar, which yielded a total of 68 peaks (signals) for the soluble in hexane, 100 peaks for the soluble in toluene, and 100 peaks for the soluble in a mixed solvent of methylene chloride and methanol (1:1 volume ratio) fractions. Have been determined and identified 22 organic compounds soluble in hexane, 45 organic compounds soluble in toluene and 21 organic compounds soluble in a mixed solvent of methylene chloride and methanol fractions from each related totally registered peaks. On the basis of proximate and ultimate analysis have been confirmed that the Shivee Ovoo coal is a low-rank lignite coal of B2 mark and it is suitable for thermal processing including pyrolysis.

Particulate matter (PM) is a complex mixture of particles that changes over time and from place to place; however, most PM is caused by the fuel combustion of motor vehicles and industry. PM is associated with acute and chronic illnesses, such as pulmonary and cardiovascular diseases. Medellin is one of the most polluted cities in Latin America. Therefore, the physicochemical characterization of its PM is necessary to understand its composition and effect on human health. In this study, PM was characterized by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) analysis, Fourier infrared spectroscopy (FTIR), inductivity-coupled plasma optical emission spectrometry (ICP-OES), and thermogravimetric analysis (TGA) in order to evaluate its morphology and chemical composition. The SEM of the PM exhibited primary particles and agglomerates. The size of the particles ranged between 0.056 and 4.5 μm. The EDS revealed elements such as carbon, silicon, calcium, lead, and iron. Furthermore, carbon monoxide, carbon dioxide, and carbonyl and aliphatic functional groups were observed by means of FTIR. Additionally, weight losses associated with volatile matter and elemental carbon were identified in the TGA analysis. The TGA and FTIR confirmed the presence of fuel and lubricant traces. Subsequently, lead was selected among the most common components in the PM in order to conduct an in silico study into its effect on ventricular activity. Lead showed a pro-arrhythmic effect by shortening the duration of the action potential under normal electrophysiological conditions, which could be associated with cardiovascular diseases.