Thermochemical Methods Research Articles

Migration and Transformation of Heavy Metals During the CO2-Assistant Thermal Treatment of Oily Sludge

Thermal treatment has significant advantages in resource recovery for oily sludge (OS). However, the instability of heavy metals (HMs) within the residue poses a considerable risk of secondary pollution. This study explored the migration and transformation of HMs from OS under varying conditions (i.e., temperature, constant-temperature duration time, and different ratios of O2 and CO2). The elevation of the pyrolysis temperature augmented the decomposition of organic matter and total petroleum hydrocarbons (TPHs). However, the increased temperature also diminished the stabilization of HMs, and facilitating the HM’s transfer to oil and gas, particularly for HMs (i.e., As and Pb) with low boiling points. The constant-temperature duration time exhibited a weak impact on HM transformation, but the internal heating mechanism of microwave pyrolysis promoted the stabilization of HMs through vitrification. The existing O2 with oxidizing properties facilitated the oxidation of organic matter and TPHs to CO2 and H2O, which also promoted the transformation of HMs into oxidized states for stabilization. Comparatively, CO2 promoted the thermal cracking and disrupted the stability of HMs to a certain extent. Above all, this work revealed the migration and transformation of HMs in OS varied with the thermochemical methods and possessed an important significance for the immobilization and stabilization of HMs.

Recent advances in anion exchange membrane technology for water electrolysis: a review of progress and challenges

AbstractClean energy and environmental pollution are two key concerns of modern society and are pivotal necessities for the economic, social, and sustainable development of the world. Today around 80% of energy is generated using nonrenewable resources and fossil fuels (oil, gas, coal) which ultimately results in hazardous global emissions. As a clean substitute for fossil fuels, hydrogen has emerged as a promising and renewable energy resource. Utilization of this energy resource requires the development of active, stable, low‐cost environmentally friendly techniques. Water splitting electrolysis is a method for producing clean and efficient hydrogen using an environmentally benign technique that is currently at its most mature stage. Electrolysis is attracting ever‐increasing attention, as it is a promising electrochemical device for hydrogen production from water due to the high conversion efficiency and relatively low energy input required when compared to thermochemical and photocatalytic methods. This paper will outline the need, performance, and insight of anion exchange membrane (AEM) electrolyzer. Recent developments in the design and preparation of AEM. New strategies for activity, stability, and efficiency improvement of AEM. Membrane types, and factors affecting AEM performance in an electrolyzer. This review also discusses the effects, operating characteristics, and energy consumption of electrocatalysts in the AEM electrolyzer. Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) pathways and mechanisms in acidic and alkaline media. This study seeks to provide a detailed overview of recent accomplishments in the field of the hydrogen economy, particularly electrolysis, to inspire further research and development to address the technology's obstacles.

Hydrogen in Burners: Economic and Environmental Implications

For centuries, fossil fuels have been the primary energy source, but their unchecked use has led to significant environmental and economic challenges that now shape the global energy landscape. The combustion of these fuels releases greenhouse gases, which are critical contributors to the acceleration of climate change, resulting in severe consequences for both the environment and human health. Therefore, this article examines the potential of hydrogen as a sustainable alternative energy source capable of mitigating these climate impacts. It explores the properties of hydrogen, with particular emphasis on its application in industrial burners and furnaces, underscoring its clean combustion and high energy density in comparison to fossil fuels, and also examines hydrogen production through thermochemical and electrochemical methods, covering green, gray, blue, and turquoise pathways. It discusses storage and transportation challenges, highlighting methods like compression, liquefaction, chemical carriers (e.g., ammonia), and transport via pipelines and vehicles. Hydrogen combustion mechanisms and optimized burner and furnace designs are explored, along with the environmental benefits of lower emissions, contrasted with economic concerns like production and infrastructure costs. Additionally, industrial and energy applications, safety concerns, and the challenges of large-scale adoption are addressed, presenting hydrogen as a promising yet complex alternative to fossil fuels.

Selective Leaching of Lithium and Beyond: Sustainable Eggshell-Mediated Recovery from Spent Li-Ion Batteries

This study introduces an innovative strategy for the selective leaching of lithium from spent Li-ion batteries. Based on thermodynamic assessments and exploiting waste eggshells as a source of calcium carbonate, an impressive 38% of lithium was dissolved selectively through mechanical milling and water leaching, outperforming conventional thermochemical methods. Afterwards, a hydrogen peroxide-assisted sulfuric acid leaching was also implemented to solubilize targeted elements (Mn, Co, Ni, and Li), with an exceptional 99% efficiency in Mn removal from the leachate using potassium permanganate and a pH range of 1.5 to 3.5. Selective separations of Co and Ni were then facilitated utilizing CYANEX 272 and n-heptane. This comprehensive study presents a promising and sustainable avenue for the effective recovery of Li and associated co-elements from spent lithium batteries.

Chemical thermodynamics of biomass, cellulose, and cellulose derivatives: A review

This article provides a review of the research on the chemical thermodynamics and thermochemistry of biomass, cellulose, and its derivatives such as ethers, esters, and oxycelluloses. For diverse biomass types, gross and net heating values were studied. It has been established that these energetical characteristics of biomass can be calculated using a superposition of the energetical characteristics of the main components of biomass such as cellulose, hemicelluloses, lignin, lipids, proteins, etc. The pelletization of biomass improves its fuel performance. It was shown that, if the ultimate goal is to generate the maximum amount of thermal energy, then it is more profitable to directly burn the initial biomass in the form of pellets than to burn the amount of solid or liquid biofuel that can be extracted from this biomass. After the cellulose study, the direct and exact thermochemical method for determining the crystallinity degree of this biopolymer was proposed. In addition, the standard combustion and formation enthalpies of various cellulose samples were studied. As a result, the thermodynamic characteristics of four crystalline allomorphs of cellulose, CI, CII, CIII, and CIV, were obtained and their thermodynamic stability was evaluated. The thermochemistry of enzymatic hydrolysis of cellulose was studied. In addition. The thermodynamical characteristics of various cellulose derivatives were determined, and the thermochemistry of the reactions of cellulose alkalization, etherification, esterification, and oxidation was studied.

A novel Ca-Ni looping with carbonation heat thermochemical regeneration method for post-combustion CO2 capture: System integration, energy-saving mechanism, and performance sensitivity analysis

Thermal coupling between the calcium looping (CaL) process and chemical looping combustion (CaL-CLC) offers advantages to avoid electricity consumption of air separation, and the CaL-CLC has presented superior performance realizing CO2 capture. However, in these CaL-CLC and CaL configurations for post-combustion CO2 capture, the carbonation heat is recovered for steam generation with a significant temperature difference, leading to considerable irreversible loss. To prevent the temperature mismatch during carbonation heat recovery, this paper proposes the concept of Ca-Ni looping with the carbonation heat thermochemical regeneration method. Additionally, a novel system integrating with a combined cycle is introduced to effectively decarbonize flue gas. Results show that the proposed system has superior performance compared with the reference system based on the Ca-Cu looping method. The specific energy consumption for CO2 avoided (SPECCA) decreased from 2.13 MJ/kg CO2 in the reference system to 1.43 MJ/kg CO2. Exergy analysis indicates that a total 6.3 % exergy destruction reduction is realized by replacing the Cu-based chemical looping combustion with the Ni-based oxidation reaction for calcination heat supply. Furthermore, the energy utilization diagram (EUD) reveals the mechanism of exergy destruction reduction caused by the thermal coupling between reaction processes. Besides, the impact of key operating parameters on the proposed system performance is investigated. Overall, the proposed Ca-Ni looping with carbonation heat regeneration method enhances the utilization of mid-temperature carbonation heat by converting it into high-grade thermal energy suitable for combined cycles, thereby offering a promising alternative for low-energy-consumption CO2 capture.

Study on the deep deoxidation mechanism of titanium powder using Y/YOCl/YCl3 and Y/Y2O3 systems

Low-oxygen high-purity titanium (oxygen concentration ≤ 500 ppm) is a critical material for advanced semiconductor and biomedical applications. Current deoxidation methods limit oxygen concentration in titanium to approximately 1000–2000 ppm, failing to meet the demand for ultra-low oxygen levels in high-performance materials. This study investigated the preparation mechanism and conditions for low-oxygen high-purity titanium utilizing a molten salt thermochemical method, employing Y as the deoxidant with a theoretical deoxidation limit below 10 ppm. We experimentally explored the deoxidation mechanisms of titanium using Y/YOCl/YCl3 and Y/Y2O3 systems, successfully reducing the oxygen concentration in titanium to 200 ppm, and proving that the Y/YOCl/YCl3 system is more efficient than the Y/Y2O3 system. Additionally, the titanium samples were analyzed using SEM-EDS, XRD, XPS, and 3D surface profilometry before and after deoxidation. These analyses examined the impact of the deoxidation process using Y on the crystal structure, oxide film, and surface roughness of titanium specimens, which are useful for understanding the deoxidation mechanism. During the sintering process of titanium powder attached to Y, the deoxidation process will produce YOCl or Y2O3. The formation of these deoxidation products leads to local oxygen diffusion, and the crystals of YOCl or Y2O3 are gathered at grain boundaries, which will resolve during the subsequent acid etching process, thus reducing the oxidation concentration of the titanium. The above results provide further theoretical guidance and technical support for the production of ultra-high-purity titanium powder.

Experimental and performance analysis of organic fraction of municipal solid waste in downdraft gasifier

It is anticipated that the production of municipal solid waste will increase from 2.10 billion tonnes in 2023 to 3.80 billion tonnes by 2050. About 170 billion metric tonnes of biomass is produced worldwide each year. On a wet basis, the composition of municipal solid waste (MSW) includes approximately 20% of wood, 70% of food waste, 60% of yard trimmings, and 50% of other organic materials. Gasification of waste biomass is one of the most efficient processes for creating gaseous fuel and subsequently power with reduced environmental impact. The current work presents a novel strategy to reduce MSW by converting waste into briquettes and feeding it in gasifiers to produce syngas. The downdraft gasifier is employed in the syngas generation process. With a calorific value of 22.6 MJ/kg and a higher lignin concentration of approximately 31%, MSW proves to be suitable for thermochemical conversion processes. This article presents the results during gasification of briquette made from organic fraction of municipal solid waste (OFMSW) with significant heating value of 22.6 MJ/kg. The fuel produced by the gasifier has a heating value ranging from 920 to 1150 kcal/m3, making it clean-burning. Its primary components consist of 19% to 23% carbon monoxide and 17% to 21% hydrogen. This study offers a unique investigation into the gasification behavior of the organic fraction of OFMSW in a downdraft gasifier, with an emphasis on optimizing operational parameters and evaluating the yield and quality of syngas. Although gasification has been widely studied as a thermochemical conversion method for biomass, the specific performance of OFMSW in this process has received limited attention. By focusing on this underexplored area, the study enhances the understanding of OFMSW's potential in gasification and its contribution to sustainable energy production, thereby addressing key issues in both waste management and renewable energy generation.

Trends and challenges in hydrogen production for a sustainable energy future

AbstractRecurring environmental challenges and the global energy crisis have led to intensified research on alternative energy sources. Hydrogen has emerged as a promising solution, produced through electrochemical, thermochemical, and biological methods. This study presents the advantages and disadvantages of these technologies. It also provides pertinent data on hydrogen production, identifying world‐leading countries in hydrogen production, such as the USA, Japan, and China, and the government policies that they have adopted. It reports market trends such as hydrogen synthesis by water electrolysis, the high cost of the electrolyzers used, and incentives for the carbon market to become competitive with other alternative energy sources. It also highlights startups from around the world that are developing innovative methodologies for producing hydrogen. The study concludes that integrating hydrogen production concepts with social, environmental, and industry interests is essential.

Integrated experimental and DFT-based study on pH-dependent photoelectrochemical performance of Ca2Fe2O5

In this study, photoelectrochemical (PEC) performance of Ca2Fe2O5 nanoflakes were explored to understand corrosion and degradation tendency. Ca2Fe2O5 nanoflakes were synthesized via a modified two step thermochemical method consisting of hydrothermal reaction and chemical conversion. Detailed characterization using SEM, XRD, and TEM confirmed the highly crystalline and (200) faceted Ca2Fe2O5 nanoflake morphologies. PEC measurements, conducted in six distinct electrolyte conditions, revealed significant photocurrent variations with respect to pH change, highlighting pH 11 as the optimal environment. Electrochemical impedance spectroscopy (EIS) was applied to elucidate charge transfer rate depending on the hydrogen evolution reaction (HER) mechanisms. Furthermore, DFT calculations provided insights into the surface interactions of Ca2Fe2O5 with hydrogen and hydroxide absorbates, elucidating the electronic and structural change during PEC reactions. The simulation demonstrated that, while hydrogen adsorption induced Fe-O bond dissociation, hydroxide adsorption showed minimal effect on surface bonds. HER overpotentials were calculated for both Tafel and Volmer step, elucidating the facile and stable HER in OH terminated surface environments. These findings underscore the importance of alkaline electrolyte environment in optimizing the PEC stability and efficiency of Ca2Fe2O5 photocathodes.

Experimental evaluation of municipal solid waste air-gasification in a pilot-scale reciprocating moving-grate furnace

The increasing volume of municipal solid waste (MSW) worldwide presents significant environmental challenges, necessitating the development of efficient waste-to-energy (WtE) solutions. Among various thermochemical methods, gasification offers a promising approach for converting MSW into syngas, which can be utilized for energy generation. This study investigates the gasification characteristics of MSW in a pilot-scale reciprocating moving-grate furnace, focusing on the effect of key operating parameters such as equivalence ratio (ER), gasification temperature, and gasifying agent-staged ratio on gasification characteristics.Seven experimental schemes were tested with varying lower heating values (LHV) of MSW (ranging from 6.98 to 15.1 MJ/kg) and throughputs (ranging from 0.77 to 1.67 tons per day) to assess the adaptability and stability of the moving-grate system under different conditions. The results indicate that an ER between 0.6 and 0.7, a gasification temperature of 760 °C, and a gasifying agent-staged ratio of 7:3 are optimal for achieving a maximum energy conversion efficiency of 71.6 %. It was observed that the LHV of syngas decreases when the gasification temperature exceeds 850 °C due to increased oxidation of light hydrocarbons. Moreover, the study highlights the influence of grate moving speed on residence time and reaction completeness, which are critical for optimizing syngas yield and quality.The findings demonstrate that while the maximum energy conversion efficiency of the moving-grate system is lower than other reactor types, its lower capital and operating costs, due to the lack of dedicated feedstock pretreatment, make it a viable option for small-scale and pilot-scale applications. This study provides valuable insights into optimizing MSW gasification processes and underscores the potential of the moving-grate furnace for adaptable and cost-effective WtE applications. The novelty of this work lies in the comprehensive evaluation of the moving-grate gasification process under varied operating conditions, providing a foundation for future research on improving efficiency and reducing environmental impact in large-scale MSW management.

Extraction of sustainable and low-emission hydrogen from hydrogen-blended natural gas driven by multi-product sequential separation

Blending hydrogen in natural gas, taking advantage of the readily available pipeline transportation, is considered as a highly promising means of sustainable hydrogen deployment on a vast scale. However, re-obtaining hydrogen from the mixture for end users via conventional separation technologies could pose practical challenges both energetically and economically, due primarily to the relatively low blending ratio (<30 vol%). In contrast to the commonly adopted pressure swing adsorption (PSA) separation, we propose a thermochemical approach of deriving hydrogen with synergistic capture of CO2 by steam reforming of the mixture to tackle such challenges. The process is simulated by a two-dimensional model validated by experimental data. Three typical scenarios with hydrogen blending ratios of 0–30 vol% are investigated in the operating temperature range of 300–400 °C and natural gas pipeline pressure of ≤ 40 bar. Results show that in all scenarios the amount of hydrogen recovered can exceed the amount of renewable hydrogen initially blended and additional hydrogen could be contributed thermochemically, all at relatively low energy cost. Thermochemical methods increase the partial pressure of target products, reducing separation energy and increasing yield. For the typical 10 vol% blending ratio (widely adopted), when considering the separation of hydrogen at the end user and compressing the separated off-gas before transporting it to the next end user, the hydrogen separation cost, after counterbalancing with the revenue from carbon dioxide, is only 1.33$/kgH2 with the new approach. This corresponds to a decrease by over 70.2 % as compared with that of the PSA separation cost (4.45$/kgH2). The captured CO2 in its high-purity form helps to reduce the final cost of hydrogen by a maximum of 0.33$/kgH2. The new route shows great potential for integrated hydrogen production, hydrogen purification and carbon capture for the promotion of renewable energy, green hydrogen and related technologies.

Preparation of solid alkali activator for geopolymer synthesis using vanadium-bearing shale tailing

The vanadium-bearing shale tailing (VST) with large reserves pollutes the environment and urgently needs to be utilized as a resource. Due to its main component being silica, VST has great potential as a raw material for geopolymer. Therefore, this study uses VST to prepare the solid alkali activator (SAA) by thermochemical methods. Analysis show that the temperature and NaOH dosage of thermochemical reaction significantly affect the alkaline activation effect of SAA. Temperature affects the silicate content and the amount of NaOH affects the soluble silicate content in SAA. When the reaction temperature is high (such as above 900 ℃) and the amount of sodium hydroxide is low (such as the mass ratio of sodium hydroxide to VST is 0.6), quartz almost transforms into silicates, but the silicates have a stable cyclic chemical structure and are difficult to dissolve during the geopolymerization reaction. When the reaction temperature is low (such as less than 700 ℃) and the amount of sodium hydroxide is high (such as the mass ratio of sodium hydroxide to VST is 0.9), quartz in VST is difficult to fully convert into silicates, there are unreacted quartz and sodium hydroxide in SAA, and SAA has poor alkaline activation performance. The optimal synthesis process conditions for SAA are as follows: synthesis temperature is 900 °C and the mass ratio of sodium hydroxide to VST is 0.95. The main silicate components of SAA are Na2SiO3 and Na15.6Ca3.8Si12O36. During the synthesis of one-part geopolymer (OPG), Na2SiO3 dissolution generates a strong alkaline reaction environment and provides active silicon-oxygen tetrahedron monomers or oligomers, Na15.6Ca3.8Si12O36 is bonded with geopolymer gel structure by stable cyclic silicate structure, which makes OPG have a compact integrated structure. When the mass ratio of SAA to MK is 1:1.3, the 7-day compressive strength of the prepared OPG is about 49 MPa, SAA has the potential as a substitute for commercial sodium silicate to prepare geopolymers.

A review of recent advances and applications of inorganic coating for oil and gas pipe systems

The oil and gas pipe systems are a crucial part of the infrastructure. The structural integrity of pipes is diminishing as a result of environmental damage. In recent years, the oil and gas industry has witnessed significant advancements in the development and application of inorganic coatings for pipeline systems. These coatings are essential for enhancing the durability, safety, and efficiency of pipelines by providing superior resistance to corrosion, abrasion, and chemical attacks. This review paper delves into the latest fabrication strategies for API pipe coatings, with a focus on the electroless method, electrodeposition method, thermal spray method, thermochemical method, and other emerging techniques. Each method is evaluated in terms of its principles, advantages, limitations, and suitability for different operational environments. Among the coating methods, the electroless process is one of the most popular methods. The paper also highlights innovative approaches and materials that have the potential to revolutionize the field. By providing a comprehensive overview of current technologies and their applications, this review aims to guide future research and development efforts, promoting the adoption of advanced inorganic coatings in the oil and gas industry to ensure the longevity and integrity of critical infrastructure.

Research Progress on Lignin Depolymerization Strategies: A Review.

As the only natural source of aromatic biopolymers, lignin can be converted into value-added chemicals and biofuels, showing great potential in realizing the development of green chemistry. At present, lignin is predominantly used for combustion to generate energy, and the real value of lignin is difficult to maximize. Accordingly, the depolymerization of lignin is of great significance for its high-value utilization. This review discusses the latest progress in the field of lignin depolymerization, including catalytic conversion systems using various thermochemical, chemocatalytic, photocatalytic, electrocatalytic, and biological depolymerization methods, as well as the involved reaction mechanisms and obtained products of various protocols, focusing on green and efficient lignin depolymerization strategies. In addition, the challenges faced by lignin depolymerization are also expounded, putting forward possible directions of developing lignin depolymerization strategies in the future.

Resource utilization of coal-derived sludge and low-rank coal by multi-step thermochemical co-treatment method

Both coal-derived sludge and low-rank coal possess significant potential for resource utilization and have garnered considerable attention in recent years. The TG−DTG analysis method showed that the thermal conversion components of coal-derived sludge tended to migrate to coal and interacted with low-rank coal. The dewatering effect of low-rank coal on coal-derived sludge was investigated using the sludge-specific resistance to filtration (SRF) method. The results showed that the addition of coal promoted the transformation of interstitial water and surface water of sludge, especially the interstitial water to free water. Dewatering and deoxidation of low-rank coal and coal-derived sludge were realized by decarboxylation and C−O bond cleavage on benzene during hydrothermal co-treatment at 140−220 ℃. The average water content of hydrochar was 3.96 % after hydrothermal co-treatment, and its calorific value increased from 19.77 MJ/kg to 21.74 MJ/kg after hydrothermal co-treatment. Hydrothermal oil was produced during hydrothermal co-treatment. GC−MS analysis showed that the contents of N and S increased in the hydrothermal oil with the increase of hydrothermal temperature, indicating that the hydrothermal co-treatment can remove the impurity elements (such as N and S) contained in coal-derived sludge and low-rank coal. The pyrolysis experiments of the hydrochar at 600–900 ℃ showed that the hydrochar produced less pyrolysis gas and emitted less CO2 than the result without hydrothermal co-treatment. This study provided an effective strategy for the treatment and resource utilization of sludge and coal.

A novel molecular structure parameter determination method for biomass thermochemical conversion mechanism investigation

The low-grade energy properties and high O content of biomass limit its efficient energy utilization. Torrefaction is known to be one of the most promising thermochemical conversion methods for upgrading biomass. 250 °C Gas-pressurized (GP) torrefaction realizes deep decomposition of hemicellulose in biomass to as high as 99.7% by deoxygenation and aromatization. However, the above thermochemical conversion mechanism at molecular-level is currently scant. Here, a novel molecular structural parameter method and pure hemicellulose torrefaction were employed to investigate the thermochemical conversion mechanism. Results demonstrate that O content of 250 °C GP torrefied hemicellulose was as low as 28.8 wt%, which was considerably lower than 44.6 wt% of traditional torrefied hemicellulose. There are five deoxygenation mechanisms of hemicellulose during the GP torrefaction: deacetylation, decarbonylation, dehydroxylation, ring opening and cyclization reactions to produce CO2/CH3COOH, CO, H2O, ketones/aldehydes and furans. The deoxygenation and aromatization reactions cause the chemical structure of hemicellulose evolution significantly, these mechanisms are: active hemicellulose undergo aromatization reaction through cyclization and deoxidation to generate preliminary 2-ring furans polymer, followed by stepwise polymerization reactions to form 4-ring and 6-ring furans polymers. These polymerization reactions further greatly enhance deoxygenation reaction. A thermochemical conversion mechanism model is developed based on the above investigation. This work provides a novel method for determining the molecular structure and reaction mechanism of thermochemical converted biomass.

Maximizing thermal performance in triangular honeycomb thermochemical reactors: Structural and operating parameter studies

Using thermochemical energy storage methods to store energy is increasingly vital for boosting the share of renewable energy in consumption within buildings and industries. This entails harnessing off-peak excess renewable energy, such as electricity or waste heat energy, for storage purposes. While previous research emphasizes the importance of improving reactor performance, comprehensive analysis of the new honeycomb reactor designs is lack. Innovative advancements in maximizing thermal performance within triangular honeycomb reactors are elucidated in this study. This study employs a validated 3-D model to explore the effects of these parameters on heat and mass transfer within a triangular honeycomb reactor. By investigating structural and operational parameters, a novel equilibrium is achieved, amplifying heat exchange efficiency and channeling thermal energy with unprecedented precision. Through a rigorous examination of reactor air velocity distribution, air temperature lift, and outlet air absolute humidity, this research unveils pivotal insights into enhancing reactor efficacy. Notably, the study identifies that increasing the channel thickness by 1.2 times, resulting in energy storage density of 463 kJ/kg. This innovation positions triangular honeycomb reactors at the forefront of sustainable energy management, offering a potential solution for decarbonization such as storing industrial waste heat and harnessing surplus off-peak electricity in buildings.

The mechanism on liquefaction of waste tire by ethanolysis

Thermo-chemical treatment methods are pivotal for effectively managing waste tire rubber (WTR) while promoting energy efficiency and emission reduction. This study investigates the liquefaction of WTR within a thermal ethanol environment, exploring temperature ranges (200–300 °C) and residence times (0–80 min) to discern the role of ethanol in tire degradation. Additionally, the study includes liquefaction experiments with cyclohexane as a solvent to contrast the effect of ethanol, and comparison between ethanol and water to elucidate solvent impact. Results indicate that at 300 °C for 40 min, oil yields peak at 53.05 % for a WTR/ethanol mass ratio of 1:8 and at 51.64 % for a ratio of 1:6, notably surpassing hydrolysis outcomes. By contracting with the results from the liquefaction with cyclohexane as solvent, the involvement of ethanol can facilitate liquid phase products, primarily alkenes and oxygen-containing compounds, attributed to aromatization inhibition. Heavy oils and heteroatomic compounds are characterized through Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), detecting hydrocarbons and heteroatom compounds like NxOy, Ox, Sx, NxOySz, NxSy, and Nx. Notably, sulfur, a significant pollutant, predominantly manifests as sulfide in chars. These findings offer valuable insights into advancing waste tire recycling technologies.

Influence of Lithium Triflate Salt Concentration on Structural, Thermal, Electrochemical, and Ionic Conductivity Properties of Cassava Starch Solid Biopolymer Electrolytes.

Cassava starch solid biopolymer electrolyte (SBPE) films were prepared by a thermochemical method with different concentrations of lithium triflate (LiTFT) as a dopant salt. The process began with dispersing cassava starch in water, followed by heating to facilitate gelatinization; subsequently, plasticizers and LiTFT were added at differing concentrations. The infrared spectroscopy analysis (FTIR-ATR) showed variations in the wavenumber of some characteristic bands of starch, thus evidencing the interaction between the LiTFT salt and biopolymeric matrix. The short-range crystallinity index, determined by the ratio of COH to COC bands, exhibited the highest crystallinity in the salt-free SBPEs and the lowest in the SBPEs with a concentration ratio (Xm) of 0.17. The thermogravimetric analysis demonstrated that the salt addition increased the dehydration process temperature by 5 °C. Additionally, the thermal decomposition processes were shown at lower temperatures after the addition of the LiTFT salt into the SBPEs. The differential scanning calorimetry showed that the addition of the salt affected the endothermic process related to the degradation of the packing of the starch molecules, which occurred at 70 °C in the salt-free SBPEs and at lower temperatures (2 or 3 °C less) in the films that contained the LiTFT salt at different concentrations. The cyclic voltammetry analysis of the SBPE films identified the redox processes of the glucose units in all the samples, with observed differences in peak potentials (Ep) and peak currents (Ip) across various salt concentrations. Electrochemical impedance spectroscopy was used to establish the equivalent circuit model Rf-(Cdl/(Rct-(CPE/Rre))) and determine the electrochemical parameters, revealing a higher conduction value of 2.72 × 10-3 S cm-1 for the SBPEs with Xm = 17 and a lower conduction of 5.80 × 10-4 S cm-1 in the salt-free SBPEs. It was concluded that the concentration of LiTFT salt in the cassava starch SBPE films influences their morphology and slightly reduces their thermal stability. Furthermore, the electrochemical behavior is affected in terms of variations in the redox potentials of the glucose units of the biopolymer and in their ionic conductivity.