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This study investigated the enhancement of WO₃/Rh composite gas sensors for improved acetone detection. WO₃/Rh composite samples (WO₃/Rh-1, WO₃/Rh-2, WO₃/Rh-3) were synthesized via spray pyrolysis, and materials were studied using XRD, SEM, and TEM. These analyses confirmed successful introduction of Rh nanoparticles and indicated favorable alterations in structure and morphology. Gas sensing tests with varying acetone concentrations (0.1–4 PPM, balanced with simulated exhaled gas with RH% of ∼30 %) demonstrated that Rh introduction significantly improved sensitivity and selectivity. Notably, WO₃/Rh-3 exhibited the highest performance, with enhanced response times and selectivity critical for diabetes monitoring. These results highlight the potential of WO₃/Rh sensors in medical diagnostics, offering a promising approach for the early detection of diabetes through breath analysis. [ABSTRACT FROM AUTHOR]

The brittleness and limited plastic deformation of ceramics restrict their applications. In this work, the effects of pristine (CNT P), functionalized (CNT OH , CNT COOH) and silanized MWCNTs on the mechanical properties of Silicon Carbide obtained by pyrolyzing polycarbosilane SMP-10 were studied. Functionalization with 3-glycidoxypropyltrimethoxy was analyzed through dispersion stability, zeta potential, and EDS analyses, revealing increased silicon content and colloidal stability in silanized MWCNTs. However, silanized MWCNTs led to reduced mechanical properties in composites, while untreated MWCNTs (CNT P , CNT OH , CNT COOH), showed a substantial increase in modulus by 74.2 %, 86.9 %, and 30.5 %, respectively. The observed enhancement in mechanical properties exceeded the outcomes predicted by the rule of mixtures, suggesting notable morphological changes induced by MWCNTs. Potential underlying factors including toughening mechanisms and changes in porosity were evaluated and discussed in depth. Composites with untreated MWCNTs showed nearly a two-fold increase in fracture toughness. This work shows a streamlined approach for the development of ceramic nanocomposites (CNCs), achieving significant improvement in mechanical properties through pyrolysis, surpassing traditional methods reliant on densification processes. These findings demonstrate the substantial potential of CNCs, enhancing their suitability for advanced engineering applications. [ABSTRACT FROM AUTHOR]

Coal in high-temperature deep mines or igneous intrusion mines is prone to complicated spontaneous combustion in the mining process, because it has occurred in a pyrolysis state for a long time. In order to investigate the effect of initial pyrolysis on coal oxidation, in this study, the coal samples were first pyrolyzed to different temperatures in the nitrogen atmosphere and then oxidized in the dry air atmosphere. Meanwhile, the changes in radical parameters (linewidth of ESR spectra, g factor and radical concentration), CO release and O2 content in the process of changing the states of coal samples from pyrolysis to oxidation at 70°C, 110°C, 150°C and 190°C were determined through experiments. The following conclusions were drawn: When the coal samples change from the pyrolysis state to the oxidation state, their linewidths of ESR spectra increase suddenly, and such an increase is more obvious when the change is made at a lower temperature. The linewidth increases by more than 0.066 mT after the change at a temperature lower than 110°C. Initial pyrolysis promotes the turning point temperature of g factor, and the turning point temperatures of g factor of coal after the gas atmosphere is changed from nitrogen to dry air at 70°C, 110°C, 150°C and 190°C are 160°C, 180°C, 190°C and 200°C, respectively. The growth rate of radical concentration surges after the change from the pyrolysis state to the oxidation state, and the radical concentrations of the coal samples whose states are changed after 150°C grow faster than that of the coal sample oxidized in dry air. When the temperature is lower than 110°C, the CO release under the pyrolysis and oxidation conditions is low, the maximum value being only 105 ppm. At the final temperature of 230°C, when the gas atmosphere is changed from nitrogen to dry air at 70°C, 110°C, 150°C and 190°C, the CO produced by coal is 14,386 ppm, 13220 ppm, 11836 ppm and 10,287 ppm, respectively. The mode of the effect of initial pyrolysis on coal spontaneous combustion was discussed in the end, and the conclusions are of guiding significance for coal spontaneous combustion control. [ABSTRACT FROM AUTHOR]

The effects of void defect sizes on the hotspot formation and pyrolysis mechanism of the high-energy cocrystal 4,40,5,50-tetranitro-2,20-bi-1H-imidazole/2,4,6-triamino-5-nitropyrimidine-1,3-dioxide (TNBI/TANPDO) were quantitatively assessed by ReaxFF-lg molecular dynamics simulations. Nanosized defects can boost the enhancement of temperature in the surrounding localized regions, generating hotspots in the defective areas and triggering pyrolysis reactions. The formation of larger voids results in the generation of more intense hotspots, which in turn leads to the occurrence of more violent chemical reactions and the production of a greater number of reaction products in a shorter period of time. The decomposition rates of the components TNBI and TANPD vary with the temperature and defect size. The activation energies of defective crystals are lower, reflecting their higher sensitivity. These discoveries may offer a valuable reference for the development of new cocrystal explosives. [ABSTRACT FROM AUTHOR]

Vat photopolymerized 3D printing technology can be used to fabricate ceramics with complex shapes. However, the extensive use of photosensitive resins as binders is not conducive to achieving crack-free ceramic green parts, especially the Si 3 N 4 ceramics with the weak interlayer bonding. In this work, the influence of different debinding atmosphere on the pyrolysis process of organics in vat photopolymerization 3D printed Si 3 N 4 green parts was investigated. The results showed that the use of 95 vol% N 2 +5 vol% H 2 atmosphere can effectively inhibit the cracking during the debinding process, especially the wall thickness of the 3D printed defect-free Si 3 N 4 green body was successfully increased to 5 mm, and the obtained sintered Si 3 N 4 ceramics exhibited higher true densities and better mechanical properties. The debinding atmospheres proposed in the current work provided additional options of debinding atmosphere for achieving high-performance 3D printed Si 3 N 4 ceramics and are expected to be expanded to other photosensitive slurry systems, with the potential to enable the production of ceramic components with the larger wall thicknesses. [ABSTRACT FROM AUTHOR]

Anaerobic digestion and composting of biowastes are vital pathways to recycle carbon and nutrients for agriculture. However, plastic contamination of soil amendments and fertilizers made from biowastes is a relevant source of (micro‐) plastics in (agricultural) ecosystems. To avoid this contamination, plastic containing biowastes could be pyrolyzed to eliminate the plastic, recycle most of the nutrients, and create carbon sinks when the resulting biochar is applied to soil. Literature suggests plastic elimination mainly by devolatilization at co‐pyrolysis temperatures of > 520°C. However, it is uncertain if the presence of plastic during biomass pyrolysis induces the formation of organic contaminants or has any other adverse effects on biochar properties. Here, we produced biochar from wood residues (WR) obtained from sieving of biowaste derived digestate. The plastic content was artificially enriched to 10%, and this mixture was pyrolyzed at 450°C and 600°C. Beech wood (BW) chips and the purified, that is, (macro‐) plastic‐free WR served as controls. All biochars produced were below limit values of the European Biochar Certificate (EBC) regarding trace element content and organic contaminants. Under study conditions, pyrolysis of biowaste, even when contaminated with plastic, can produce a biochar suitable for agricultural use. However, thermogravimetric and nuclear magnetic resonance spectroscopic analysis of the WR + 10% plastics biochar suggested the presence of plastic residues at pyrolysis temperatures of 450°C. More research is needed to define minimum requirements for the pyrolysis of plastic containing biowaste and to cope with the automated identification and determination of plastic types in biowaste at large scales. [ABSTRACT FROM AUTHOR]

High-energy global requirements have caused a renewed interest in studying and developing new and improved energy storage devices and, precisely, the electrode materials that compose them, which play a fundamental role in determining the device's performance. Carbon materials are first-class candidates due to their high electrical conductivity, chemical stability, and surface area. Although several carbon materials and their precursors have been studied, melamine sponges stand out for their nitrogen content, allowing them to act as a template and precursor for N-doped, ultralight carbon materials with good mechanical properties and a controlled pore size distribution. This work reports a simple and quick methodology to form ultralight and flexible carbon foam, along with the influence of the pyrolysis temperature on the physicochemical and electrochemical properties of 3D carbonaceous substrates used for energy storage and synthesized from melamine sponges. The substrates exhibit higher 3D porous structure than previously reported materials, with an average pore diameter of 80–90 µm. This morphology, added to the N content, promotes the remarkable electrochemical behavior (MS–950 °C) and cycling stability (MS–1000 °C) of almost 100% of capacitance retention after 10,000 cycles (≈ 60 F/g @1 A/g). [ABSTRACT FROM AUTHOR]

The oxide-rich lunar surface regolith can be used to extract the oxygen needed for the future of lunar exploration efforts as a consumable for life-support systems and spacecraft propulsion. Various techniques for the extraction of oxygen have been developed already, with solar vapor-phase pyrolysis shown to be a promising yet understudied approach. In contrast to other techniques, it requires only locally available resources, such as unbeneficiated regolith, sunlight, and vacuum in order to liberate oxygen and oxygen-bearing molecules. This study presents experimental work conducted in a purpose-built solar-vacuum furnace showing the evaporation of sodium and iron from a regolith simulant sample and their deposition on the crucible surface. This is matched by the thermochemical equilibrium modeling done in FactSage, which analyzes the process at varying pressures down to ultra-high vacuum. It highlights the need for precise temperature and pressure control, as well as the impact of regolith composition on oxygen dissociation for an efficient extraction of molecular oxygen. • The thermochemical model of the process shows molecular oxygen yields of up to 14.1%. • Low-Titanium Mare is the most promising composition for oxygen production. • Vapor-phase pyrolysis of regolith was demonstrated in a small solar furnace. [ABSTRACT FROM AUTHOR]

The current study aims to model and optimize the catalytic pyrolysis of plastics, incorporating an agricultural biomass waste-derived catalyst. Polystyrene (PSW) and polypropylene (PPW) are experimented with thermal and catalytic pyrolysis. Agricultural biomass waste (wheat husk) was selected and acid treated with sulfuric acid (HZSM-5SA) and hydrochloric acid (HZSM-5CA), and then used as catalyst. Thermal and catalytic pyrolysis were conducted in a semi batch reactor, with reaction temperature (500 ℃) and different ratios (10:1, 10:2 & 10:3). At a ratio 10:2, PSW with HZSM-5SA produced 91.19 wt.% of oil yield and PPW with HZSM-5SA produced 85.73 wt.% of oil yield. The catalyst HZSM-5SA was effective in the reduction of reaction temperature and time, it decreased from 450 ℃ to 437 ℃ and 22 min to 14 min for PSW. Catalyst activity was also observed for PPW, the reaction temperature decreased from 471 ℃ to 456 ℃ and 34 min to 19 min. Oil properties were determined and it was found that the kinematic viscosity of oil obtained from PSW with HZSM-5SA was 2.53 cSt, which coincide with the diesel Bharat Stage (BS VI 2020). Total conversion of pyrolysis products was predicted using six Machine Learning (ML) models such as Random Forest, Support Vector, K-Nearest Neighbor, Decision Tree, AdaBoost, and Gradient Boost. Among all the models, the Gradient Boost regressor model had a good evaluation metrics of R2 value of 0.984 and RMSE of 0.019, respectively. This study illustrates the use of ML models to predict the total conversion and their correlation matrix with target and feature variables. This study also highlights that cost-effective catalyst can be prepared from biomass (wheat husk) and the use of ML models to train the datasets and evaluate the actual and predicted values. Highlights: In situ catalytic pyrolysis of PSW and PPW was experimented. HZSM-5 prepared from agricultural biomass waste (wheat husk). Enhanced liquid yield of 91.19 wt.% obtained for PSW + HZSM-5SA. 70.19 wt.% of diesel-like fractions obtained in oil yield. Machine Learning model—Gradient Boost algorithm predicted the total conversion of products with R2 0.984. [ABSTRACT FROM AUTHOR]

More than 41% of households and 2.8 billion people worldwide depend on solid fuels including coal. The available coal reserves in Indonesia are 31.7 billion tons and only enough for the next 65 years. This makes the government encourage the development of research on the utilization of biomass waste as alternative energy. Efforts are made to convert biomass waste in the form of rubber wood into alternative solid fuels through the pyrolysis process. Biochar is produced from biomass through pyrolysis, resulting in excellent combustion quality. Biochar from pyrolysis is combined with brown coal and molasses adhesive to create coal biobriquettes as an alternative solid fuel. The purpose of this study was to identify the optimal composition of brown coal and biochar in producing coal biobriquettes with the best quality. The pyrolysis process of rubber wood waste was carried out at a temperature of 350-400 °C for 2 hours. This study used variations in the composition of biochar (75%, 80%, 85%, 90%, and 95%) and brown coal (5%, 10%, 15%, 20%, and 25%) and 15 mL molasses adhesive. Testing the combustion quality of coal biobriquettes through proximate analysis and value. The results showed that the most optimal product was a sample with a composition of 85% biochar and 15% brown coal. [ABSTRACT FROM AUTHOR]

The generation of N2 during coal pyrolysis has the potential to significantly reduce NOx emissions during coal combustion. Understanding the mechanism of N2 formation is critical for NOx reduction. In this paper, two dinitrogen-containing armchair model coals were selected: one with two N atoms numbered 2 and 7 on the carbon surface (R1), and another with two N atoms numbered 2 and 6 on the carbon surface (R2), to investigate the effect of different active sites on N2 production during coal pyrolysis. The density functional theory (DFT) was used to investigate the formation paths of N2 at the microscopic level. The findings indicate that the different dinitrogen active sites of the armchair structure mainly change the electronic properties of the carbonaceous surface, which results in a slight difference in the energy barrier required for the fracture of the C-N bond in the structure. The energy barriers for stripping the first N of R1 and R2 were 196.59 kJ/mol and 188.99 kJ/mol, and for stripping the second N atom were 167.21 kJ/mol and 179.31 kJ/mol. However, different active sites have no effect on the main pyrolysis paths of the armchair structure. The rate-determining steps of the two structures are a dinitrogen six-membered ring converted to a dinitrogen four-membered ring and the same intermediate (IM2 in R1 pyrolysis process and IM4 in R2 pyrolysis process) was formed after the stripping of two N atoms. Furthermore, the reaction process of IM2 → P1 (product 1) in R1 pyrolysis is consistent with IM4 → P2 (product 2) in R2 pyrolysis. [ABSTRACT FROM AUTHOR]

Countercurrent flame propagation and quenching behavior in a packed bed of spherical polymethyl methacrylate (PMMA) beads in an upward flow of pure oxygen was experimentally studied. Monosized PMMA beads of 2, 5, 8 or 10 mm in diameter (d) were packed in a vertical quartz tube of 35 mm ID to form a bed of 180 mm in height. In a typical experimental run, upon ignition from the top, a blue flame formed and propagated downwards. For d = 10, 8, or 5 mm, there existed a minimum oxygen flow rate (q) to sustain a quasi-steady state flame propagation, and the minimum q increased as d decreased from 10 to 5 mm. However, for d = 2 mm, it was not possible for the flame to propagate downwards irrespective of the q value. The apparent pyrolysis rate (mpy) of PMMA was estimated by monitoring the bed mass loss rate, from which the nominal equivalence ratio upon flame quenching was also estimated. The equivalence ratio was found to be less than unity upon flame quenching, suggesting insufficient pyrolysis gases to sustain the combustion. The heat transfer between flame and PMMA bead was analyzed theoretically, and it was revealed that the minimum mpy to sustain the quasi-steady state flame propagation inversely correlates with the PMMA particle size, and therefore a higher oxygen flow rate is required to sustain the flame propagation in a packed bed of smaller PMMA particles. [ABSTRACT FROM AUTHOR]

The impact of pyrolysis gas composition and the underlying reaction kinetics on the burning characteristics of a leaf was computationally investigated. The computational configuration resembled a previous experimental setup where vertically oriented manzanita (Arctostaphylos glandulosa) leaves were burned. Different compositions and reaction kinetics for the pyrolysis gas released during the leaf thermal decomposition were examined. The most detailed composition included $${\rm{C}}{{\rm{H}}_4}$$ C H 4 , $${\rm{CO}}$$ CO , $${\rm{C}}{{\rm{O}}_2}$$ C O 2 , and $${{\rm{H}}_2}$$ H 2 , which was suggested by the previous experimental study of pyrolysis products of different plant species. The least involved compositions only included either $${\rm{C}}{{\rm{H}}_4}$$ C H 4 or $${\rm{CO}}$$ CO . In all considered compositions, in addition to pyrolysis gas, the release of the heavy gas, i.e. tar, was accounted for. Tar breakdown was represented by a single-step reaction with the light gases above and soot as the products where the stoichiometric coefficients were determined by an optimization technique for consistency with the measurements for the tar molecule. The burning simulation results agreed best with the previous experimental data when a mixture of $${\rm{C}}{{\rm{H}}_4}$$ C H 4 , $${\rm{CO}}$$ CO , $${\rm{C}}{{\rm{O}}_2}$$ C O 2 was used. The least agreement was noted when pyrolysis gas was represented by only $${\rm{C}}{{\rm{H}}_4}$$ C H 4 . Inclusion of tar breakdown reaction appreciably increased the overall heat release due to combustion of its products above the leaf. [ABSTRACT FROM AUTHOR]

This study investigates the residual tensile behaviour of hybrid Carbon Glass fibers reinforced thermoplastic PEEK laminates after they were exposed for 5 min to a hydrogen/oxygen flame. This flame results in a severe thermal aggression characterized by a wall temperature ranging from 900 to 1270 °C and with different heat fluxes (from 200 to 800 kW/m2). The thermally-induced damages were examined by means of microscopic observations and micro CT analyses. The results show that the mass loss linearly depends on the measured heat flux for a 5 min exposure. Depending on the fire testing conditions, the mechanical properties in tension (stiffness and strength) are totally degraded after exposure to the highest heat fluxes (600 and 800 kW/m2) but the retention of the tensile properties is moderate (about −35 to −60% decrease in strength and stiffness, respectively) after exposure to a 200 kW/m2 heat flux. The residual tensile properties of CG/PEEK laminates follow master curves representing the correlations between the mass loss and the changes in the tensile properties regardless the heat flux. These master curves provide a relevant design rule for composite parts to be used under critical service conditions (H 2 /O 2 flame exposure). • The influence of a H 2 /O 2 flame on the behaviour of composite materials was studied. • Wall temperature ranges from 900 to 1270 °C for heat fluxes from 200 to 800 kW/m2. • The mechanical properties are totally degraded after exposure to 600–800 kW/m2. • The changes in the tensile properties are correlated to the mass loss. • Master curves provide a criterion to design composite parts under H 2 /O 2 flame. [ABSTRACT FROM AUTHOR]

The iron and steelmaking industries play a significant role in the manufacturing sector but result in significant greenhouse gas emissions. Biochar has recently gained attention as a potential substitute for coal in metallurgical processes due to its carbon capture potential. This review explores the potential of biochar as a sustainable substitute for coal in steelmaking industries. Notable research works have shown that substituting biochar in amounts ranging from as low as 5 % to as high as 50 % can be feasible and beneficial in processes such as coke making, iron sintering, blast furnaces, and electric furnaces. The information presented in this review can be applied to create sustainable and competitive alternatives to fossil fuels to help decarbonize metallurgical industries. [ABSTRACT FROM AUTHOR]

ABSTRACT Designing efficient noble metal‐free catalysts for plasma‐catalytic ammonia synthesis is significant and challenging. Carbon‐based metal catalysts were prepared at different pyrolysis temperatures using the Ni‐MOF‐74 precursor. The effects of Ni‐MOF‐74 and its derived carbon‐based metal catalysts on pulsed dielectric barrier discharge (DBD) plasma ammonia synthesis were investigated. The results showed that Ni‐MOF‐74‐300 with both the MOF structure and nickel metal particles exhibited the best catalytic performance for ammonia synthesis. The ammonia synthesis rate reached 41.38 mmol g−1 h−1, whereas the nitrogen conversion rate was as high as 1.54% with an energy yield of 3.04 g kWh−1. Compared to the situation of plasma only, the ammonia synthesis rate, nitrogen conversion rate, and energy yield were increased by 28.46 times, 5.7 times, and 5.5 times, respectively. [ABSTRACT FROM AUTHOR]

All layers of MASnI2Br-based perovskite solar cells (PSCs) were deposited by ultrasonic spray pyrolysis method. The depositions of the layers were carried out in a large area. The perovskite thin film deposited on FTO/TiO2 had large grains. The crystallite size of the film was calculated as 90 nm from the XRD pattern. The bandgap of 1.54 eV was determined from the UV-visible measurement of MASnI2Br thin film. The PSCs with the different active areas (0.3 cm2 and 3.18 cm2) were fabricated. The champion cells' power conversion efficiencies were recorded at 0.181% and 0.120% for 0.3 cm2 and 3.18 cm2, respectively. [ABSTRACT FROM AUTHOR]

This study focuses on the optimization and comprehensive characterization of biochar synthesized from date palm seeds (DPS), a prevalent agricultural waste in arid regions. Using response surface methodology (RSM) with a central composite design (CCD), we optimized the pyrolysis process by investigating the effects of time (1–3 h) and temperature (600–900 °C) on critical properties such as specific surface area, pore volume, and yield. The optimized biochar, produced at 828 °C for 1.7 h, demonstrated a high specific surface area of 654.8 m2/g and well-developed microporosity. Characterization techniques, including XRD, FTIR, SEM–EDS, and BET analyses, revealed an amorphous carbon structure with graphitic domains, diverse surface functionalities, and a heterogeneous porous microstructure. The biochar's point of zero charge at pH 7.58 indicates its potential for selective adsorption of charged contaminants. The close agreement between RSM-predicted and experimental values for specific surface area (652.1 m2/g vs. 654.8 m2/g) and micropore volume (0.191 cm3/g vs. 0.190 cm3/g) validates the effectiveness of the model in optimizing biochar properties. This research highlights the potential of DPS-derived biochar as a sustainable adsorbent for environmental remediation, opening avenues for valorizing agricultural wastes and contributing to circular economy principles. [ABSTRACT FROM AUTHOR]

This study evaluates the potential of several biomasses differing in nature and composition for their valorization by pyrolysis and in line oxidative steam reforming. The first task involved the fast pyrolysis of the biomasses in a conical spouted bed reactor (CSBR) at 500 °C, in which product yields were analyzed in detail. Then, the oxidative steam reforming (OSR) of pyrolysis volatiles (gases and bio‐oil) was approached in a fluidized bed reactor (FBR). The reforming experiments were performed at 600 °C, with a steam/biomass (S/B) ratio of 3 and catalyst (Ni/Al2O3) space times of 7.5 and 20 gcat min gvol−1. Concerning equivalence ratio (ER), a value of 0.12 was selected to ensure autothermal operation. Remarkable differences were observed in H2 production depending on the type of biomass. Thus, pine wood led to a H2 production of 9.3 wt %. The lower productions obtained with rice husk (7.7 wt %) and orange peel (5.5 wt %) are associated with their higher ash and fixed carbon content, respectively, which limit the efficiency of biomass conversion to bio‐oil. However, in the case of the microalgae, the poor performance observed is because of the lower conversion in the reforming step toward gases due to the composition of its pyrolysis volatile stream. [ABSTRACT FROM AUTHOR]

The pyrolysis of water hyacinth is gaining attention and acceptance as a resource recovery technique due to its availability and economic viability. However, the presence of lignin, one of the three major biomass fractions, presents significant challenges for profitable water hyacinth processing for biofuel production. Fungal pretreatment of water hyacinth for lignin breakdown has been explored but the application of Trichoderma atroviride as a pretreatment for pyrolysis is relatively novel. The efficacy of T. atroviride pretreatment in improving water hyacinth's pyrolytic products using a fixed‐bed reactor was therefore investigated in this study. The optimization process was studied using a central composite design in response surface methodology with Design Expert 13. Delignification of the biomass was established because the elemental analysis showed a 25.42% increase in cellulose content and a 23.40% and 3.37% decrease in lignin and hemicellulose content, respectively. The biomass pretreatment applied influenced the physical and chemical characteristics of the pyrolytic products. The highest pyrolysis oil yield increased by 25.81% at 575 °C and particle size 2290 μm, and the highest char yield decreased by 4.23% at 273 °C and particle size 1500 μm. This research is crucial for policy and research conversations as it offers a scientific basis for the application of T. atroviride pretreatment in biomass pyrolysis technology and emphasizes the optimal utilization of water hyacinths to obtain socio‐environmental benefits. [ABSTRACT FROM AUTHOR]

Pyrolysis is an environmentally friendly and efficient method for converting biomass into a wide range of products, including fuels, chemicals, fertilizers, catalysts, and sorption materials. This review confirms that scientific research on biomass pyrolysis has remained strong over the past 10 years. The authors examine the operating conditions of different types of pyrolysis, including slow, intermediate, fast, and flash, highlighting the distinct heating rates for each. Furthermore, biomass pyrolysis reactors are categorized into four groups, pneumatic bed reactors, gravity reactors, stationary bed reactors, and mechanical reactors, with a discussion on each type. The review then focuses on recent advancements in pyrolysis technologies that have improved efficiency, yield, and product quality, which, in turn, support sustainable energy production and effective waste management. The composition and yields of products from the different types of pyrolysis have been also reviewed. Finally, a techno-economic analysis has been conducted for both the pyrolysis of biomass alone and the co-pyrolysis of biomass with other raw materials. [ABSTRACT FROM AUTHOR]

AbstractThe addition of carbon-rich materials, such as raw feedstocks (RAW) and biochars, to agricultural soils is on the rise. This activity has many advantages, such as improving fertility, increasing water retention, and sequestering carbon. However, they can also increase the sorption of residual herbicides in the soil, reducing the effectiveness of weed control. Thus, the objective of this study was to evaluate soil improvement and the sorption–desorption process of diclosulam in soil unamended and amended with RAW from olive stone and their biochars produced in two pyrolysis temperatures (300 and 500 °C). Oxisol was used in this study, unamended and amended with RAW and biochars (BC300 and BC500) in a rate of 10% (w w−1). The sorption–desorption process was assessed by batch-equilibrium experiments and the analysis was performed using high-performance liquid chromatography (HPLC). The addition of the three materials to the soil increased the contents of pH, organic carbon, P, K, Ca, Mg, Zn, Fe, Mn, Cu, B, cation exchange capacity, base saturation and decreased H + Al. The unamended soil had Kf (Freundlich sorption coefficient) values of diclosulam sorption and desorption of 1.56 and 12.93 mg(1 − 1/n) L1/n Kg−1, respectively. Unamended soil sorbed 30.60% and desorbed 13.40% of herbicide. Soil amended with RAW, BC300, and BC500 sorbed 31.92, 49.88, and 30.93% of diclosulam and desorbed 13.33, 11.67, and 11.16%, respectively. The addition of RAW and biochars from olive stone has the potential to change the soil fertility, but does not interfere with the bioavailability of diclosulam in weed control under field conditions, since the materials slightly influenced or did not alter the sorption–desorption of diclosulam. [ABSTRACT FROM AUTHOR]

Recently, we investigated the interaction mechanism of 1H-tetrazole (1H-TZ) and nitrocellulose (NC). Next, we tried to introduce an amino group at the C and N atoms of 1H-tetrazole, so as to explore the influence of amino group modification on the pyrolysis process of NC. The focus of this study was on investigating the interaction mechanism of aminotetrazole (5-ATZ or DATZ) and NC through kinetics methods and TG-DSC-FTIR analysis. The quenching and reheating experiments revealed that the imino form of 5-ATZ or DATZ played an important role in this process. The addition of aminotetrazole (5-ATZ and DATZ) mainly affected the autocatalytic reaction at the initial stage of the pyrolysis process of NC. TG-DSC-FTIR experiments revealed that there was a chemical reaction between NO2 and decomposition products of 5-ATZ or DATZ. In this reaction, R–N＝C＝NH or N≡C–NH–R (R = H and NH2) reacted with NO2 to form N2O and CO2. [ABSTRACT FROM AUTHOR]

Pharmaceutical packaging is one of the most used packaging types which contains aluminum and plastics. Due to increasing amounts of waste and rising environmental concerns, recycling approaches are being investigated. Since blisters usually contain a balanced amount of plastics and metals, most of the approaches focus on recycling only one material. Therefore, more sustainable recycling approaches which recover both plastic and aluminum fractions are needed. This study investigates the thermal behavior and degradation mechanisms of plastic-rich and aluminum-rich pharmaceutical blisters using various analytical techniques. Structural characterization revealed that plastic-rich blisters have a thicker profile with plastic and aluminum layers, while aluminum-rich blisters consist of plastic layers between aluminum sheets. Thermal degradation analysis showed two main stages for both types: plastic-rich blisters (polyvinyl chloride) exhibited significant weight loss and long-chain hydrocarbon formation between 210 and 285 °C, and aluminum-rich blisters (polyamide/nylon) degraded from 240 to 270 °C. Differential Scanning Calorimetry and Fourier Transform Infrared Spectroscopy analyses confirmed the endothermic behavior of such a transformation. The gas emissions analysis indicated an increased formation of gasses from the thermal treatment of plastic-rich blisters, with the presence of oxygen leading to the formation of carbon dioxide, water, and carbon monoxide. Thermal treatment with 5% O2 in the carrier gas benefited plastic-rich blister treatment, reducing organic waste by up to 80% and minimizing burning risk, leveraging pyrolytic carbon for protection. This method is unsuitable for aluminum-rich blisters, requiring reduced oxygen or temperature to prevent pyrolytic carbon combustion and aluminum oxidation. [ABSTRACT FROM AUTHOR]

Green biorefineries can support the reduction of soybeans imports to Europe, by producing protein-rich animal feed from alternative feedstock such as perennial grass and legume species. Once the protein-rich green juice is extracted, a fiber-rich pulp is left as a residue. This work investigates the thermochemical processing of the pulp via pyrolysis as an option to improve the energy balance and climate footprint of a green biorefinery, by producing non-fossil energy and a high-value biochar product. Laboratory-scale pyrolysis and biochar activation were carried out on pulp samples obtained from different perennial species, different pressing method, and maturity at harvest. The results highlighted the importance of the activation stage to obtain a porous biochar, potentially suitable as animal feed additive. The effects on the overall energy balance and climate impact of the system following the integration of pulp drying and pyrolysis, plus a possible activation step for the biochar, were evaluated with a techno-environmental assessment. The pulp sample composition had only limited influence on the climate impact potentials identified. In all cases, it was found that the integration of a combined drying-pyrolysis-activation system in the green biorefinery may provide substantial additional climate benefits but also that the magnitude of these is strongly dependent on the substitution use-value of the energy products. [ABSTRACT FROM AUTHOR]

This work explores the conversion of raw poultry manure (RPM) into tailor-made biochars for an efficient phosphorus (P) recovery from aqueous solutions. To this end, three RPM-functionalized biochars with Mg (RPM-B-Mg), Al (RPM-B-Al), and Mg/Al-layered double hydroxides (RPM-B-Mg/Al-LDHs) were synthetized, deeply characterized, and then tested for P recovery under various experimental conditions. Biochar characterization showed that RPM-B-Mg/Al-LDHs had enhanced texture and surface chemistry linked to the formation/deposition of Mg- and Al-based nanoparticles. In addition, this biochar exhibited the highest P recovery rate from effluents (78 mg g−1). This recovery process seems to occur heterogeneously on multilayers through electrostatic interactions, ligand exchange, surface precipitation as AlPO4 and Mg3(PO4)2, and complexation. Phosphorus desorption from these P-loaded biochars was significantly dependent on the pH of eluent solutions with the highest desorption yield observed at an initial pH of 9.0 (88%). All these findings indicate that the use of Mg/Al-LDHs-loaded poultry manure biochar can be considered a sustainable material for P recovery from aqueous solutions. Furthermore, the P-loaded biochar could be reused in agriculture as a low-cost biofertilizer in P-depleted soils. [ABSTRACT FROM AUTHOR]

In gasification, scrubbers are generally used for cleansing syngas. In addition, the presence of tar in the production of liquid smoke presents a substantial problem due to its carcinogenic and toxic properties. In order to improve the quality of liquid smoke, a scrubber was developed as a tar absorbent for coconut shell pyrolysis. This study aimed to investigate the efficiency of a water scrubber as a method of reducing tar during coconut shell pyrolysis. Pyrolysis was performed at 500 °C for 2 h with variations in coconut shell mass. A water scrubber filled with 500 ml of water is used as a medium for absorbing tar. Physicochemical properties, functional groups, aromatic ring size, rheology, and tar compounds were identified, and the effect of the water scrubber on pyrolysis temperature, heating rate, scrubber temperature, and yield of pyrolysis products was also studied. The optimum effectiveness in reducing tar was reached at 37%. There were no significant differences in physicochemical properties, functional groups, and rheology between heavy and light tars. Tar contains one to two rings of aromatic compounds with compositions of phenols, carboxylic acids, ketones, furans, sugars, alcohols, and methyl esters. The application of a water scrubber has been shown to affect the absorption of polar compounds, particularly phenol and carboxylic acids. The use of a water scrubber has been observed to be an effective technique for reducing tar content during pyrolysis, resulting in the production of liquid smoke. [ABSTRACT FROM AUTHOR]

In this study, dark tea residue (DTR) and polypropylene (PP) were used as the experimental raw material, and the method that combined wet torrefaction (hydrothermal carbonization) and pyrolysis was used to analyze and study it – analyzing the surface functional group composition of pyrolytic carbon by Fourier infrared spectrometer and analyzing the porosity and specific surface by specific surface area analyzer. We used the GC and the GC-MS to analyze the components of pyrolysis gas and bio-oil. The results showed that wet torrefaction could increase the specific surface area and porosity of solid products and optimize the physical and chemical properties of the surface of pyrolytic carbon. At the same time, it could reduce the oxygen content of liquid products and improve the quality of bio-oil, increase the relative content of CH4and H2in gas products, and improve the availability of pyrolysis gas. The co-pyrolysis could increase the yield of gas products and the hydrogen content of liquid products. [ABSTRACT FROM AUTHOR]

Valorization of flax shives biomass is investigated through pyrolysis and in-line catalytic hybrid reforming. We demonstrate that this approach enables the conversion of the biomass into three valuable products namely syngas, biochar, and bio-oil while reducing the emissions of greenhouse gases (CH4 and CO2). Given the increasing attention to syngas and especially hydrogen, pyrolysis and reforming reactor parameters were adjusted to enhance syngas production. Analyzed biochar properties such as contents of carbon (>82%), oxygen (<5%), and hydrogen (<1.5%) are conform to the European Biochar Certificate. The bio-oil composition analysis showed that the main compounds were benzene, toluene, phenols, guaiacol, syringol, furfural, and some polycyclic aromatic hydrocarbons, which were converted to lighter species by the reforming. Among the catalysts tested (cobalt, nickel, and cobalt-nickel supported on alumina beads), nickel provided the highest H2 production (8.26 mmol/gdry biomass or 37.41 vol.%). Nickel loading was varied from 0 to 25% with a maximum H2 production obtained with 20%Ni/Al2O3 (11.17 mmol/gdry biomass or 40.13 vol.%). Increasing the reforming temperature from 650 to 800°C enhanced the gas formation (53 wt.%) and the conversion rates of CH4 (62.6%) and CO2 (48.3%). An aging test was also performed on the 20%Ni/Al2O3 revealing a drop in the catalyst activity and stability. The catalysts characterization was realized by determining their porosity, specific surface area, weight loss, and SEM images. It revealed that sintering and carbon deposition are the main reasons behind their deactivation. [ABSTRACT FROM AUTHOR]

Boron doping of biochar leads to the formation of activated oxygen species and pores and defects in the carbon structure Therefore, boron-containing biochar was prepared by treating boric acid (H3BO3) solutions in different concentrations of hazelnut shells before pyrolysis. DSC results showed that treatment of biomass with solutions containing a low concentration (0.1 wt. %) of H3BO3 increased the degradation of cellulose and hemicellulose, but also increased char formation. However, treatment with solutions containing 2% and 5% H3BO3 increased biochar oxidation with the formation of boron oxide (B2O3). The FT-IR and XPS results showed the presence of B–B, B–O, and B–O–B in the H3BO3 treatment, which is due to the formation of B2O3. The examination of the proliferation of L929 mouse fibroblast cells in response to different concentrations of boron-containing biochars using the MTT assay revealed that biochar treated with 2% H3BO3 promoted cell growth (100.32 ± 1.93). However, above this concentration, the formation of polycrystalline B2O3 species exhibited an inhibitory effect on cell proliferation (81.98 ± 1.26) in the samples of H3BO3-doped biochar with 5% concentration. The results of the in vitro hemolysis tests for undoped biochar and high boron-containing (% 5) biochar sample showed mild hemolytic activity, with percentages of 2.46 ± 0.02 and 3.08 ± 0.04, respectively, according to the reported standards. Antimicrobial studies have shown that Candida albicans (a yeast, ATCC 10231) is more sensitive to H3BO3 than Staphylococcus aureus (Gram-positive bacteria, ATCC 29213). Boron-containing biochar can be used in a variety of applications, including biosensing, drug delivery, biological scaffolds, and biological imaging, as well as an adsorbent in the removal of pollutants and a catalyst in oxidation and electrochemical reactions. [ABSTRACT FROM AUTHOR]

The escalating demand for plastic presents an immense peril to both the environment and humanity. Not only have there been notable advancements in the creation of advanced biodegradable polymers, but there has also been a lack of attention towards tackling the current issue of plastic waste. Processing fuels via plastic waste valorization provides a feasible approach to recycle plastics and mitigating pollution for the improvement of society. This review addresses a comprehensive analysis of various heterogeneous catalysts in the context of plastic pyrolysis to produce fuel, intending to identify an eco-friendly method for recycling garbage. The choice of catalyst has a substantial effect on the disintegration process of waste plastic, dictating the properties of the resulting fuel, encompassing both the amount and the quality. Pyrolysis, an alternative method for addressing the increasing waste disposal issue, is a non-toxic process that does not release hazardous pollutants, in contrast to incineration. The waste plastic serves as a feedstock for pyrolysis process, employing innovative, environmentally friendly catalysts derived from natural and other sources, to generate fuel oil that possesses similar physical characteristics to the diminishing petroleum-based fuels. This critical review analyzes the impact of different heterogeneous catalysts on the process of transforming waste plastic to produce fuel through pyrolysis. Heterogeneous catalysts are crucial to the process of turning discarded plastics into oil, offering significant potential for improving not only economic and environmental conditions but also benefiting both industry and society. [ABSTRACT FROM AUTHOR]

The engineering of biochars with desired morphologies and pore structures is a far-reaching objective towards sustainable pore-dependent environmental technologies, such as water and soil remediation or catalysis. We hereby report a series of experiments that allow the direct following of the shape and porosity of single biochar particles during pyrolysis. Particles ~ 1–2 mm in diameter of unwashed and water-washed raw walnut shells were continuously 3D imaged during pyrolysis to 575 ℃ at a 10 K min−1 in Ar to obtain time- and temperature-resolved x-ray micro computed tomographies to a 0.82 μm resolution. Results showed visual evidence of a 30% and 70% v/v particle shrinkage for unwashed and washed samples, respectively. Particle swelling between 200 and 300 ℃ in the unwashed sample provided evidence of the softening of native biopolymers associated with lignin in untreated biomass. A purpose-defined parameter Λ shows the temperature-dependence of pore re-distribution towards the center of the particle to be linear for both samples. Λ was found to be 3.2 × 10 - 4 K - 1 in the washed sample, approximately 3.5 times faster than in the unwashed one. Such linear dependence is significantly slower than an exponential Arrhenius-like trend thereby providing a qualitative measure of the heat and mass transport phenomena limiting the chemical reactions in the porous medium. This evidence is key to resolving the pathways to the thermochemical decomposition of biomass leading to preparation of precision-engineered biochars. Highlights: Evolution of morphology of single particle (1–2 mm) walnut shell was tracked in operando during pyrolysis via micro-CT (~ 812 nm resolution). Samples pre-washed in water didn't exhibit particle swelling observed in untreated samples in the 200–300 ℃ range. Porosity towards the center of the particle was developed 3.5 faster in washed samples than in unwashed ones. [ABSTRACT FROM AUTHOR]

AbstractThermochemical conversion (or pyrolysis) has emerged as an effective technique for the disposal of sludge generated in process industries. This paper reports physicochemical characterization and kinetic analysis of pyrolysis of sludge from a petroleum refinery and characterization of resultant char. The sludge had high volatile matter (>70 wt%) and low ash content (15 wt%). Pyrolysis of sludge was studied using a thermo-gravimetric analyzer (TGA). The TGA data was analyzed using two isoconversional models, viz. KAS and Vyazovkin AIC are used for the deduction of kinetic triplets, viz. activation energy, pre-exponential factor, and reaction mechanism. The activation energy (Ea) of sludge pyrolysis varied in the 64.79–190.37 kJ/mol range. The pre-exponential factor varied from 1.18E + 07 to 4.29E + 12 s−1. The predominant solid-state mechanism of thermal conversion was an order-based reaction (F2/F3). The thermodynamic factors (viz. ΔH, ΔS, ΔG) of sludge pyrolysis were also determined. Relatively small values of (Ea – ΔH) ∼ 5 kJ/mol revealed high susceptibility of sludge for thermal conversion. Residual char after pyrolysis was characterized for physicochemical properties. The char properties were fixed carbon = 54.37%, calorific value = 22.48 MJ/kg, and BET surface area = 18.35 m2/g. These properties make char suitable for numerous applications. [ABSTRACT FROM AUTHOR]

The carbon spheres synthesized by pyrolysis of resorcinol–formaldehyde (RF) semiconducting resins exhibit enhanced activity for electrocatalytic oxygen reduction. The spheres consist of narrow reticulated carbon layers, which are derived from the donor–acceptor π-stacking interaction of the resins, and show high electron conductivity. [ABSTRACT FROM AUTHOR]

Graphene-based nanomaterials have been proved to be robust sorbents for efficient removal of environmental contaminants including arsenic (As). Biobased graphene oxide (bGO-P) derived from sugarcane bagasse via pyrolysis, GO-C via chemical exfoliation, and magnetite nanoparticles (FeNPs) via green approach using Azadirachta indica leaf extract were synthesized and characterized by Ultraviolet-Visible Spectrophotometer (UV-vis.), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), mean particle size and Scanning electron microscopy (SEM) along with Energy dispersive spectroscopy (EDX) analysis. Compared to cellulose and hemicellulose, the lignin fraction was less in the precursor material. The GOC, bGO-P and FeNPs displayed maximum absorption at 230, 236, and 374 nm, respectively. FTIR spectrum showed different functional groups (C-OH, C-O-C, COOH and O-H) modifying the surfaces of synthesized materials. Graphene based nanomaterials showed clustered dense flakes of GO-C and thin transparent flakes of bGO-P. Elemental composition by EDX analysis of GO-C (71.26% C and 27.36% O), bGO-P (74.54% C and 24.61% O) and FeNPs (55.61% Fe, 4.1% C and 35.72% O) confirmed the presence of carbon, oxygen, and iron in synthesized nanomaterials. Sorption study was conducted with soil amended with different doses of synthesized nanomaterials (10, 50 and 250 mg) and exposed to 100, 300 and 500 ppm of As. Arsenic concentrations were estimated by colorimetry and atomic absorption spectroscopy (AAS). GO-C, bGO-P, and FeNPs showed substantial As removal efficiency i.e., 81 to 99.3%, 65 to 98.8% and 73.1–89.9%, respectively. Green synthesis of bGO-P and magnetite nanoparticles removed substantial amounts of As compared to GO-C and can be effectively deployed for As removal or immobilization. Higher and medium sorbent doses (250 and 50 mg) exhibited greater As removal and data was best fitted for Freundlich isotherm evidencing favorable sorption. Nevertheless, at low sorbent doses, data was best fitted for both models. Newly synthesized nanomaterials emerged as promising materials for As removal strategy for soil nano-remediation and can be effectively deployed in As contaminated soils. [ABSTRACT FROM AUTHOR]

The synthesis of high‐entropy alloys (HEAs) with ultra‐small particle sizes has long been a challenging task. The complex and time‐consuming synthesis process hinders their practical application and widespread adoption. This study presents the novel synthesis of TiO2 nanoparticles loaded with a quinary high‐entropy alloy through flame spray pyrolysis (FSP) for the first time. The extremely fast heating rate of flame combustion makes the precursor fast pyrolysis gasification, high temperature in the flame field promotes the metal vapor mixing uniformly, and the fast quenching process can reduce the particle aggregation sintering, the ultra‐small particle size of HEA firmly attached to the TiO2 surface. The catalysts prepared via this gas‐to‐particle pathway exhibit excellent performance in CO2 hydrogenation, achieving a conversion rate of 62% at 450 °C, and maintaining their activity for over 220 h without significant particle agglomeration. This finding provides valuable insights for the future design of catalytically active materials with enhanced activity and long‐term stability. [ABSTRACT FROM AUTHOR]

Three fuel grain geometries were investigated in a two-dimensional, optically accessible solid fuel ramjet combustor to improve the understanding of the internal ballistics as it pertains to flameholding and overall performance. Two-cavity flameholding-configured fuel grains demonstrated increased flameholding and similar performance to the baseline flat fuel grain. Optical diagnostics such as high-speed CH* chemiluminescence and high-speed three-color camera pyrometry were utilized to measure and analyze the emissive species to draw conclusions about the reacting flowfield. Additionally, optical access afforded the ability to determine spatially resolved regression rates within the flameholding region of each fuel grain. The measured fuel grain regression rates demonstrated similar performance between the three configurations; however, the spatial distribution of the regression rates resulting from the high local heat flux due to the cavity corner is postulated to be the driving factor in increasing the flameholding capability of the cavity fuel grains. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive model for lignocellulosic biomass pyrolysis, addressing kinetics, energy balances, and gas product composition with the aim of its application in wood combustion. The model consists of a two-stage global mechanism in which biomass initially reacts into tar, char, and light gases (non-condensable gases), which is followed by tar reacting into light gases and char. Experimental data from the literature are employed for determining Arrhenius kinetic parameters and key energy parameters, like tar and char heating values and the specific enthalpy of primary and secondary reactions. A methodology is introduced to derive correlations, allowing the model's application to diverse biomass types. This work introduces several novel approaches. Firstly, a pyrolysis model that determines the composition of light gases by solving mass, species, and energy balances is developed, limiting the use of correlations from the literature only for tar and char elemental composition. The mass rate of light gases, tar, and char being produced is also determined. Secondly, kinetic parameters for primary and secondary reactions are determined following a Shafizadeh and Chin scheme but with a modified Arrhenius form dependent on T n , significantly enhancing the accuracy of product composition prediction. Additionally, correlations for the enthalpies of reactions, both primary and secondary, are determined as a function of pyrolysis temperature. Primary reactions exhibit an overall endothermic behavior, while secondary reactions exhibit an overall exothermic behavior. Finally, the model is validated using cases reported in the literature, and results for light gases composition are presented. [ABSTRACT FROM AUTHOR]

In this work, the pyrolysis process and the characteristics of biochar produced using a bench-scale fixed-bed reactor and a prototype-scale auger reactor were studied. Residual forest biomass (RFB) from acacia, broom, gorse, and giant reed was used as feedstock. Besides information on pyrolysis characteristics of these specific biomass species from the Iberian Peninsula, new knowledge on the understanding of how results from small-scale reactors can be used to predict the behavior of higher-scale and continuous-operation reactors is offered. Batch pyrolysis was carried out using 40 g of biomass sample in a fixed-bed reactor with a heating rate of 20 °C∙min−1, pyrolysis temperature of 450 and 550 °C, and a residence time of 30 min, while for the continuous process it was used a prototype of an auger reactor with continuous operation with a biomass flow rate up to 1 kg/h, with temperatures of 450 and 550 °C, and a solids residence time of 5 min. The biochar yield was in the range of 0.26 to 0.36 kg/kg biomass dry basis, being similar for both types of reactors and slightly lower when using the auger reactor. The proximate analysis of the biochar shows volatile matter in the range 0.10 to 0.27 kg/kg biochar dry basis, fixed carbon in the range 0.65 to 0.84 kg/kg biochar dry basis, and ash in the range 0.04 to 0.08 kg/kg biochar dry basis. The carbon, oxygen, and hydrogen content of the biochar was in the range of 0.71 to 0.81, 0.09 to 0.22, and 0.02 to 0.03 kg/kg biochar dry basis, respectively. The results show that the up-scaling of the reactor and regime of operation does not have an important influence on the yield and characteristics of the biochar produced. The biochar obtained in the two types of reactors has characteristics appropriate for environmental applications, such as an additive to improve soil properties. It is possible to see that the characteristics of the biochar are influenced by the type of biomass and the conditions and parameters of the process; therefore, it is of major importance to control and know of these conditions, especially when considering upscaling scenarios. [ABSTRACT FROM AUTHOR]

Submicron and nanosized powders have gained significant attention in recent decades due to their broad applicability in various fields. This work focuses on ultrasonic spray pyrolysis, an efficient and flexible method that employs an aerosol process to synthesize titanium-based nanoparticles by transforming titanium oxy-sulfate. Various parameters are monitored to better optimize the process and obtain better results. Taking that into account, the influence of temperature on the transformation of titanium oxy-sulfate was monitored between 700 and 1000 °C. In addition to the temperature, the concentration of the starting solution was also changed, and the flow of hydrogen and argon was studied. The obtained titanium-based powders had spherical morphology with different particle sizes, from nanometer to submicron, depending on the influence of reaction parameters. The control of the oxygen content during synthesis is significant in determining the structure of the final powder. [ABSTRACT FROM AUTHOR]

In response to the issues of poor economic efficiency and high CO2 emissions in the urea-to-ammonia technology of thermal power plants, this paper innovatively proposes a new ammonia production process for thermal power plants. This process utilizes the waste heat of thermal power plant boilers and conducts urea pyrolysis through two-stage heating to prepare ammonia and cyanuric acid. From this, the prepared ammonia can be used in the denitrification process of thermal power plants, and the prepared cyanuric acid can bring additional benefits to thermal power plants. The optimal process scheme was determined through orthogonal experiments of urea pyrolysis. And with the help of Aspen Plus software, a whole-process modeling analysis of urea pyrolysis experiments was carried out to investigate the influences of the melting temperature, melting time, reaction temperature, and reaction time on the process. The results show that when the melting temperature was 160 °C, the melting time was 45 min, the reaction temperature was 240 °C, and the reaction time is 20 min, which was the best scheme, 18.45% ammonia and 52.35% cyanuric acid could be obtained. Through the combined analysis of the Aspen Plus simulation and urea pyrolysis experiments, it was found that the melting temperature should be controlled within 160–167 °C, the melting time should be controlled within 40–45 min, the reaction temperature should be controlled within 240–245 °C, and the reaction time should be controlled within 15–20 min. Compared with the existing urea-to-ammonia process, this process has the advantages of nearly zero emissions and good economic benefits, thus providing reliable research data support for future industrialization. [ABSTRACT FROM AUTHOR]

The conversion of biomass-coal mixtures into energy using thermal conversion systems offers a more environmentally sustainable alternative to conventional coal consumption. A reactor with an internal compartment is proposed to improve the pyrolysis performance of lignite coal and mixtures of lignite coal with peanut shells. The study investigates lignite coal with varying moisture contents and peanut shell proportions (0%, 10%, 25%, and 50%) at a temperature of 500°C, using a heating rate of 0.1°C/s. The results indicated that dry mixtures demonstrated higher overall productivity compared to wet mixtures, particularly in terms of charcoal production. The weight of charcoal increased by 4.83%, 4.71%, 4.02%, and 2.61% across the mixtures. The total conversion rates for dry mixtures were 24.59%, 29.27%, 34.36%, and 40.44%, while for wet mixtures, the conversion rates were 29.42%, 33.98%, 38.38%, and 43.05%, respectively. The results revealed that moisture content during pyrolysis significantly influenced the productivity of lignite and lignite-peanut shell mixtures. The conversion rates in dry mixtures were lower compared to those in wet mixtures. The novelty of this work lies in its pioneering investigation of the impact of moisture on the slow pyrolysis of Turkish lignite mixed with peanut shells. It offers novel insights into optimizing the thermal conversion process for these materials by uniquely examining the effects of moisture on productivity and conversion rates. [ABSTRACT FROM AUTHOR]

Coconut shell waste can generate environmental problems if left without treatment, as it contains lignin, cellulose, and hemicellulose compounds, which pyrolyze to produce liquid smoke, charcoal, and tar. This study aims to prepare and characterize liquid smoke using several parameters, including the chemical content preserving tofu and the hedonic test of consumer preferences. The dried coconut shell (3000 g) was pyrolyzed at 300 °C for 5 h. Liquid smoke (grade 3) was purified by distillation (grade 2) and filtered with activated charcoal to produce grade 1 liquid smoke. The liquid smoke properties were characterized as yield, pH, phenol, and moisture, while the chemical components were identified by gas chromatography-mass spectroscopy (GC-MS). For the commercial and coconut shell liquid smoke (grade 1) used in this study, the application was aimed at preserving the tofu for three days. Panelists observed the aroma, the texture, and the appearance compared to the control. Ten panelists performed the hedonic test of fried preserved tofu. The organoleptic aspects included taste, texture, aroma, and color. The liquid smoke obtained from coconut shell pyrolysis was red-brown, with a yield of 52.75%, pH 0.5 (grade 3), pH 1.7 (grade 2), and pH 2.3, with a total phenol of 2.479 (grade 1). The GC-MS results exhibited three essential chemical compounds, namely phenol, methoxy phenol, and hydroxyphenyl phosphonic acid, influencing the preservation. The liquid smoke solution extended the shelf life of tofu, especially at a concentration of 1.5 (% v/v), so the water content decreased. The average panelist responded “good” on the hedonic test on all of the tofu treatments compared to the control. [ABSTRACT FROM AUTHOR]

The aim of this study is to explain the consequences of the occurrence of enthalpy–entropy compensation (EEC) and isoequilibrium relationship during slow pyrolysis of cigarette butt filters (CBFs), consisting cellulose acetate (AC) as the main component. By using model-free and model-based kinetic methods and thermodynamic calculations, the complete reaction mechanism and extrathermodynamic issues about investigated process are completely resolved. It was established that compensation phenomenon where isoequilibrium temperature occurs is a consequence of formation of low-entropy molecular structure (cellulose II) and breaking of hydrogen bonds. Consequently, it was concluded that mechanisms which include a formation of low-entropy molecular structure and H-bonds breakage enter the changes in both enthalpy and entropy, which compensate each other. For the cellulose II generation, it was necessary to invest energy which represents use up energy. This "wasted" energy turns into work for creation of cellulose II molecular structures, whereby additional energy was provided from "local" decomposition reactions (which were identified in the established process mechanism) that arise from pyrolysis of starting material. Therefore, it was concluded that for "local reactions", a negative ΔS° value was identified, but for the global process, the entropy change retained a positive value. Considering thermodynamic effects manifested through compensation temperature found below glass transition temperature (Tg) in the undercooling conditions, it was concluded that small amounts of plasticizers affect reduction of free volume in the glassy state. Obtained results indicated a decrease in β-relaxation mode of cellulose acetate by an abatement of the polymer free volume. [ABSTRACT FROM AUTHOR]

The utilization of reclaimed asphalt pavement (RAP) aggregates as an alternative for rigid pavements is limited. The main objective of this study is to explore and improve the utilization of RAP aggregates as an alternative material for rigid pavement. Specifically, this study focuses on addressing a significant challenge associated with RAP aggregates, which is their poor bond with cementitious binders. The poor bonding results in low compressive and tensile strengths of concrete or mortar. The poor bonding is mainly due to the presence of a thin oily layer of asphalt residue. A proposed method was carried out to reduce the negative impact on the bond between the aggregate and mortar by exposing the RAP aggregates to the pyrolysis process. The research focused on the analyses of the physical and chemical behavior of the aggregates, using the SEM, EDX, and FTIR approaches, as well as reviewing the mortar in both compressive and flexural tensile strength. The pyrolysis affected the physical and mechanical properties positively and the chemical composition of the RAP showed significant changes. The chemical constituents of asphalt attached to RAP aggregates are hydrocarbons. The thin layer of RAP asphalt is the cause of weak bonding, but this layer was altered by the pyrolysis procedure. As a result, water absorption decreased, which had a positive impact on the hydraulic synergy of cement. It is shown that the pyrolyzing RAP improves the compressive strength and flexural tensile strength through modification of the asphalt residue covering the aggregates. [ABSTRACT FROM AUTHOR]

• Waste coffee pods (CP) were treated using a two-stage pyrolysis process. • A microwave-assisted pyrolysis process was employed for treating waste CP. • Catalytic reforming of evolved gas yielded 76 % (by volume) hydrogen at 900 °C. • Microwave and catalysis-assisted pyrolysis process can be a solution to upcycling. Plastic waste poses a critical environmental challenge for the world. The proliferation of waste plastic coffee pods exacerbates this issue. Traditional disposal methods such as incineration and landfills are environmentally unfriendly, necessitating the exploration of alternative management strategies. One promising avenue is the pyrolysis in-line reforming process, which converts plastic waste into hydrogen. However, traditional pyrolysis methods are costly due to inefficiencies and heat losses. To address this, for the first time, our study investigates the use of microwave to enhance the pyrolysis process. We explored microwave pyrolysis for polypropylene (PP), high-density polypropylene (HDPE), and waste coffee pods, with the latter primarily comprising polypropylene. Additionally, catalytic ex-situ pyrolysis of coffee pod pyrolysis over a nickel-based catalyst was investigated to convert the evolved gas into hydrogen. The single-stage microwave pyrolysis results revealed the highest gas yield at 500 °C for HDPE, and 41 % and 58 % (by mass) for waste coffee pods and polypropylene at 700 °C, respectively. Polypropylene exhibited the highest gaseous yield, suggesting its readiness for pyrolytic degradation. Waste coffee pods uniquely produced carbon dioxide and carbon monoxide gases because of the oxygen present in their structure. Catalytic reforming of evolved gas from waste coffee pods using a 5 % nickel loaded activated carbon catalyst, yielded 76 % (by volume) hydrogen at 900 °C. These observed results were supported by elemental balance analysis. These findings highlight that two-stage microwave and catalysis assisted pyrolysis could be a promising method for the efficient management of waste coffee pods, particularly for producing clean energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • WEEE pyrolytic pseudo reactions were obtained by mathematical deconvolution method. • Pseudo reactions were identified by comparing them with the pure polymers' results. • LGE pseudo-1 with TiO 2 catalyst shows the lowest E a with a value of 92.10 kJ/mol. • Pseudo-3 and pseudo-4 are key contributors to MGE's thermal degradation. • Lowest E a : 75.24 kJ/mol in MGE pseudo-3 (HZSM-5), 226.39 kJ/mol in pseudo-4 (TiO 2) Waste electrical and electronic equipment (WEEE) has become a critical environmental problem. Catalytic pyrolysis is an ideal technique to treat and convert the plastic fraction of WEEE into chemicals and fuels. Unfortunately, research using real WEEE remains relatively limited. Furthermore, the complexity of WEEE complicates the analysis of its pyrolytic kinetics. This study applied the Fraser-Suzuki mathematical deconvolution method to obtain the pseudo reactions of the thermal degradation of two types of WEEE, using four different catalysts (Al 2 O 3 , HBeta, HZSM-5, and TiO 2) or without a catalyst. The main contributor(s) to each pseudo reaction were identified by comparing them with the pyrolysis results of the pure plastics in WEEE. The nth order model was then applied to estimate the kinetic parameters of the obtained pseudo reactions. In the low-grade electronics pyrolysis, the pseudo-1 reaction using TiO 2 as a catalyst achieved the lowest activation energy of 92.10 kJ/mol, while the pseudo-2 reaction using HZSM-5 resulted in the lowest activation energy of 101.35 kJ/mol among the four catalytic cases. For medium-grade electronics, pseudo-3 and pseudo-4 were the main reactions for thermal degradation, with HZSM-5 and TiO 2 yielding the lowest pyrolytic activation energies of 75.24 and 226.39 kJ/mol, respectively. This effort will play a crucial role in comprehending the pyrolysis kinetic mechanism of WEEE and propelling this technology toward a brighter future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Distillation enables the settlement and recovery of Li 2 CO 3 from spent electrolyte. • The oil and solid phase can be separated at a low temperature pyrolysis. • Conversion path of electrolyte concentrate during the whole process is proposed. • Addition of alkali shows well performance on fixation of fluorine and phosphorus. • A viable method is proposed for disposing the residual electrolyte. Disposal of electrolytes from waste lithium-ion batteries (LIBs) has gained much more attention with the growing application of LIBs, yet handling spent electrolyte is challengeable due to its high toxicity and the lack of established methods. In this study, a novel two-stage thermal process was developed for treating residual electrolytes resulted from spent lithium-ion batteries. The conversion of fluorophosphate and organic matter in oily electrolyte during low-temperature rotation distillation was investigated. The distribution and migration of the concentrated electrolytes were studied and the corresponding reaction mechanisms were elucidated. Additionally, the influence of alkali on the fixation of fluorine and phosphate was further examined. The results indicated that hydrolyzed carbonate esters and lithium in the electrolyte could combine to form Li 2 CO 3 and the hydrolysable hexafluorophosphate was proven to be stable in the concentrated electrolyte (45 rpm/85 °C, 30 min). It was found that CO 2 , CO, CH 4 , and H 2 were the primary pyrolysis gases, while the pyrolysis oil consisted of extremely flammable substances formed by the dissociation and recombination of chemical bonds in the electrolyte solvent. After pyrolysis at 300 °C, fluorine and phosphate were present in the form of sodium fluoride and sodium phosphate. The stability of the residue was enhanced, and the environmental risk was reduced. By adding alkali (KOH/Ca(OH) 2 , 20 %), hexafluorophosphate in the electrolyte was transformed into fluoride and phosphate in the residue, thereby reducing the device's corrosion from fluorine-containing gas. This study provides a viable approach for managing the residual electrolyte in the waste lithium battery recovery process. [ABSTRACT FROM AUTHOR]

The use of carbonaceous materials such as biochar has been considered an innovative solution in agriculture, especially to mitigate dry events caused by climate change. Biochar can improve water holding capacity, physical and chemical properties of soil, and increase the productivity of agricultural systems. However, underlying physiological mechanisms remain poorly understood. Mineral supplementation with potassium nitrate (KNO3) via foliar application is another promising strategy in agricultural management under irrigation deficit. Thus, we investigated the combined effects of biochar and foliar application of KNO3 on growth, yield, and physiology of tomato plants under different irrigation regimes. Results did not indicate a synergistic effect of biochar and foliar application of KNO3. Biochar application alleviated tomato plant stress under deficit irrigation, with plants showing better functioning of photosynthetic apparatus, higher yield, and better fruit quality, as well as increased water use efficiency. Coffee husk biochar (K-rich feedstock) fully met the tomato plant's demand for K and partially met the demand for some other elements (P, Mg, Fe, Zn, Mn, and Cu). Although positive effects of KNO3 application was verified for some physiological and fruit quality components, overall, foliar application of KNO3 did not improve tomato yield. It is concluded that biochar soil amendment can be a promising practice to increase yield and quality of tomato fruits under deficit irrigation. Therefore, biochar-based fertilizer can be an alternative K source that also provides stable carbon to soil and helps to mitigate stress caused by prolonged drought. [ABSTRACT FROM AUTHOR]