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Knowledge of the technological properties of wood is important for its use and the quality of its products. The aim was to assess the quality of charcoal produced from wood grown in the Cerrado biome. Wood samples of Handroanthus roseoalba (ipê branco), Handroanthus heptaphyllus (ipê roxo) and Piptocarpha rotundifolia ('blackheart') were selected. Charcoals from these samples were produced at two charring temperatures (500 and 550 °C). Basic density, total extractives, lignin and holocellulose, gravimetric yield, higher calorific value and immediate chemical properties of the charcoals were determined. Near infrared (NIR) spectra were obtained on the transverse and longitudinal faces of the wood using a DLP® NIRscan™ portable spectrometer. Partial least squares regression was used to adjust predictive models of charcoal properties using the NIR spectra measured in the precursor wood. The coefficients of determination in the cross-validation (R2cv) ranged from 0.49 to 0.87 for volatile materials, from 0.48 to 0.88 for fixed carbon and from 0.49 to 0.85 for higher calorific value of charcoal. The spectra generated better models for properties of charcoals produced at 500 °C. The models generated were satisfactory, indicating that the NIR spectrometry can predict the quality of charcoal before it is produced. [ABSTRACT FROM AUTHOR]

To understand the roles of charcoal and ectomycorrhizal fungi (ECMF) on tree growth, which relates to the rehabilitation of forest ecosystems after forest fires, two experiments were set up in this study, the first was to determine the correct amount of charcoal for Japanese larch (Larix kaempferi Sarg.) seedling growth by applying oak charcoal to basic soil medium at ratios of 1:1, 1:2, 1:4 and 1:8 by volume. The second experiment investigated the combined effects of four types of charcoal: derived from oak wood, husks of buckwheat, rice and activated charcoal of larch wood, and two types of ECMF: Pt (Pisolithus tinctorius Pers.) and Ec (Pt + Rhizopogon spp. + Laccaria spp. + Scleroderma spp.) on the growth of Japanese larch seedlings. Our results show that growth was significantly stressed by large amounts charcoal applications. There were significant variations among the four types of charcoal on growth. We concluded that the addition of charcoal was the critical factor that influenced larch growth and ECMF formation. Rice charcoal and Ec stimulates the growth and nitrogen uptake of Japanese larch seedlings, thus the most suitable fungus and charcoal for practices is Ec-rice charcoal (1: 8 charcoal to basic soil). [ABSTRACT FROM AUTHOR]

Escalations in wildfire activity are of significant global concern, particularly within vulnerable wetland ecosystems integral to natural carbon sequestration and climate change mitigation. Our understanding and management of future wildfire activity may be better contextualised through the study of historic and ancient fire records, independent of human influence. Methods of study include 'geothermometry' - approximating ancient fire intensity from temperature-dependent changes in the chemistry of fossil charcoal. Though well established in their relation to experimental charcoalification, these methods still fail to quantify the true intensity of ancient fires, as a measure of energy release. As a result, their applicability, and contributions to the characterisation of modern fire activity, remain uncertain. Here, we present a novel measure of wildfire energy release, as a proxy for true intensity, through the co-application of cone calorimetry and Raman spectroscopy of charcoal. By applying a range of wildfire heat fluxes to variable peatland fuel mixes, this research demonstrates the complexity in correlating fire behaviour and charcoal microstructure. Further statistical analyses suggest a correlation between spectroscopic results, measures of CO and CO2 release, and fire severity. This offers a principal measure of ancient wildfire intensity, consistent with modern practices in wildfire modelling, monitoring, and management. [ABSTRACT FROM AUTHOR]

Fossil fuel subsidy removal may hinder access to clean fuels like LPG. Our analysis of urban Senegal shows that LPG use fell sharply after subsidies ended in 2009, despite later price drops. Households switched to charcoal, and the new availability of energy-efficient charcoal stoves made a return to LPG less appealing. This highlights how energy transitions among the poor are price sensitive, with implications for subsidy and carbon-tax policies. [ABSTRACT FROM AUTHOR]

There is growing global concern regarding the detrimental health impacts of PM2.5 emissions from traditional stoves that utilize polluting fuels. Conventional methods for estimating daily personal PM2.5 exposure involve personal air samplers and measuring devices placed in a waist pouch, but these instruments are cumbersome and inconvenient. To address this issue, we developed a novel neck-mounted PM2.5 monitoring device (Pocket PM2.5 Logger) that is compact, lightweight, and can operate continuously for 1 week without recharging. Twelve participants who utilized charcoal, firewood, or propane gas for cooking in rural regions of Rwanda wore the Pocket PM2.5 Logger continuously for 1 week, and time-series variations in personal PM2.5 exposure were recorded at 5-min intervals. Individual daily exposure concentrations during cooking differed significantly among users of the different fuel types, and PM2.5 exposure was at least 2.6 and 3.4 times higher for charcoal and firewood users, respectively, than for propane gas users. Therefore, switching from biomass fuels to propane gas would reduce daily individual exposure by at least one-third. An analysis of cooking times showed that the median cooking time per meal was 30 min; however, half the participants cooked for 1.5 h per meal, and one-third cooked for over 4.5 h per meal. Reducing these extremely long cooking times would reduce exposure with all fuel types. The Pocket PM2.5 Logger facilitates the comprehensive assessment of personal PM2.5 exposure dynamics and is beneficial for the development of intervention strategies targeting household air pollution. [ABSTRACT FROM AUTHOR]

The production of açaí seed waste from the commercial and extractive exploitation of the Euterpe oleraceae palm tree is a serious problem that contributes to environmental contamination and production of greenhouse gases, a fact that suggests the need for an environmentally correct destination for this waste produced on a large scale. To this end, this study was conducted to evaluate the potential of acaí seed biochar (BCA) in mitigating the toxic effects of copper in Brazilian mahogany plants, analyzing biometrics and gas exchange. The experimental design was in randomized blocks, with five blocks, in a 4 × 3 factorial scheme, corresponding to the control (without Cu) and three concentration of Cu (200, 400, and 600 mg Cu kg−1) and three levels of BCA (0%, 5% and 10%) proportional to the amount of soil in the pots, totaling sixty experimental units. The use of 5% BCA in soils contaminated with up to 200 mg kg−1 Cu promoted biometric increase (height, diameter, number of leaves), maintaining gas exchange (photosynthesis, stomatal conductance, transpiration, internal carbon and internal/external carbon), and consequently, maintaining water use efficiency in plants under abiotic stress, resulting in plant growth. The findings of this study allow us to indicate the use of biochar in remediating and improving the growth of plants grown in copper-contaminated soils. The production of biochar from açaí seeds is an ecologically sustainable alternative, because it reduces its accumulation on public roads and contributes to reducing soil pollution. In the context of public policies, biochar production could be a source of income in the context of the bioeconomy and circular economy practiced in the Amazon, because it is produced in large quantities. [ABSTRACT FROM AUTHOR]

Biochar is recognized for its potential in mitigating climate change, especially through carbon sequestration and soil improvement. To this end, it is important to use all co-products from pyrolysis in a sustainable and economically viable way. In this study, the conversion of sugarcane bagasse at varying pyrolysis temperatures was investigated using 1H NMR spectroscopy and Chenomx for liquid fraction analysis. The yield of biochar decreased significantly from 45.3 to 3.5% with a temperature increase of 300 to 1000 °C. The morphological analysis revealed that biochar produced at lower temperatures (300 °C and 400 °C) showed tubular and spongy structures, whereas at higher temperatures (600 °C and 800 °C), the structures morphed into holes and thinned further, ultimately degrading further at 1000 °C. All samples of biochar showed characteristics promising for soil improvement and carbon sequestration (O/C < 0.4). The analysis of liquid fractions revealed that biomethanol reached its highest concentration of 19.28 mM at 800 °C, which coincided with the highest production of acetic and lactic acids. Additionally, the highest concentration of acetone was observed at 600 °C. These findings highlight the importance of optimizing pyrolysis conditions for enhanced yields of biochar and platform compounds, as well as the potential of the NMR and Chenomx in bioenergy research. [ABSTRACT FROM AUTHOR]

The present work investigated the effects of different doses of biochar (2.5%, 5%, 10%), a by-product of the pyrolysis of woody biomass, on the growth of oat plants (Avena sativa L., cv "Danko") grown under different crude oil concentrations (0.5%, 1%, 2%, 3%, 6%) added to the soil, evaluating both biometric (i.e. fresh weight) and biochemical (i.e., content of malondialdehyde and proline, and total antioxidant power) parameters. The findings indicate that biochar positively influences the fresh weight of oat plants across all concentrations of crude oil investigated. On the other hand, regarding oxidative stress, measured by malondialdehyde and proline content, biochar led to a significant reduction, with statistical significance observed at biochar concentrations > 2.5% and crude oil levels > 2% (malondialdehyde: ranging from -25% to -38%; proline ranging from -33% to -52%). Soil amendment with biochar increased the total antioxidant power, particularly at biochar concentrations > 2.5% and crude oil levels > 2% (ranging from + 20% to + 98%). These results suggest that biochar has a great potential in mitigating the negative effects of crude oil contamination on plant growth and oxidative stress levels, thereby highlighting its value as a conditioner in contaminated soils. [ABSTRACT FROM AUTHOR]

Firewood and charcoal are the most dominant sources of fuel for domestic cooking applications in sub-Saharan Africa. In this study, performance and emission characteristics of firewood and charcoal from five commonly used species, namely, Dichrostachys cinerea, Morus Lactea, Piliostigma thonningii, Combretum molle, and Albizia grandibracteata were obtained. The water boiling test and emissions monitoring system for CO, CO2, and PM2.5 were used to determine fuel and energy consumption, thermal efficiency and emissions, and emissions' factors. The results showed that firewood combustion required higher energy consumption compared to charcoal combustion. High-power thermal efficiency was the highest (> 45%) for all charcoal derived from the firewood species. During hot-start, cold-start, and simmering operations, it was observed that thermal efficiencies were generally higher for charcoal fuels (≥ 80%) compared to the firewood (< 40%) from where they were pyrolyzed. Firewood has a much lower indoor CO emissions footprint when compared to using charcoal. Nonetheless, CO emission levels for both firewood and charcoal exceed the Environmental Protection Agency (EPA) guidelines of 35 ppm (1-h average). CO2 emission factors are the most dominant and highest contributors to greenhouse gas emissions from household use of firewood and charcoal. Overall, this work re-affirms the need for proper ventilation when firewood and charcoal are used in combustion. [ABSTRACT FROM AUTHOR]

It is difficult to utilize steel mill sludge because of the high concentration of heavy metals included therein. To passivate the activity of heavy metals, reduce their toxicity, and create a new valuable product, in this study, 4 kg sludge was composted with a combination of earthworms and different ratios (2%, 4%, and 8%) of bamboo charcoal. The effects of bamboo charcoal and the combination of bamboo charcoal and earthworms on the changes of heavy metals in industrial sludge were examined. The results showed that under the 8% bamboo charcoal ratio, addition of bamboo charcoal alone increased the concentrations of heavy metals, while the addition of bamboo charcoal combined with earthworms reduced it in sludge. The application of bamboo charcoal transformed the available state to iron-manganese bound and residue fraction in the sludge, thus reducing the bioavailability of heavy metals. Addition of bamboo charcoal and earthworms promoted the transformation percentage of heavy metals in exchangeable, carbonate, organic matter, and iron-manganese fractions to the residue fraction in sludge, which further decreased the bioavailability of heavy metals. Vermicomposting with 8% bamboo charcoal achieved maximal heavy metal passivation. Correlation and redundancy analyses showed that composting with a combination of bamboo charcoal and earthworms mainly altered the total phosphorus content, which affected the bioavailability of heavy metals. Addition of earthworms and bamboo charcoal to sludge significantly reduced the total contents of heavy metals and their bioavailability, promoted the conversion of heavy metals to the residue fraction, and improved sludge availability. [ABSTRACT FROM AUTHOR]

Acidic wastewater from mining activities contains a large amount of Sb(III). Biochar can provide with an economical and efficacious method for removing of Sb(III). However, highly efficient removal was still challenging under acidic environment. In this study, bamboo charcoal biochar and rice straw biochar were modified with glutaraldehyde and chitosan to examine their Sb(III) adsorption performances in terms of adsorption isotherms, adsorption kinetics and thermodynamics under different treatment conditions, i.e. biochar dosages, pH values, adsorption durations, coexisting substances and temperatures. Characterizations including Brunauer–Emmett–Teller surface area analysis, Fourier transform infrared spectrometry, scanning electron microscope coupled with energy dispersive X-ray spectrometry as well as X-ray photoelectron spectroscopy were employed to further reveal the mechanisms. Results showed that the modified bamboo biochar and modified rice straw biochar showed excellent Sb(III) adsorption efficiency of 94.29% and 93.36%, respectively, under strongly acidic environment. The maximum Sb(III) adsorption capacities of the modified bamboo biochar and modified rice straw biochar reached to 81.16 mg/g and 72.92 mg/g, respectively. Langmuir adsorption isotherm model and quasi-secondary kinetic model best described the adsorption processes. Thermodynamic studies showed that the adsorption of Sb(III) by modified biochar was a spontaneous, exothermic and irreversible process. It was proposed that electrostatic attraction, complexation with functional groups (e.g., C = O, -NH2, -OH), as well as oxidation of Sb(III) were involved in the adsorption processes. The modified biochar has greater removal capacity for Sb(III) than pristine one, suggesting its potential applications for the wastewater treatment. [ABSTRACT FROM AUTHOR]

This research focuses on examining the potential impact of charcoal briquettes and lumps on human health due to the emissions they release, and verifying their quality standards. Quality assessment was conducted using a device capable of measuring toxic gases to identify contaminants from various sources such as biomass, synthetic resins, coal, metals, and mineral matter. Toxicity assessments were carried out on five types of briquettes and two varieties of lump charcoal. All charcoal samples were subjected to elemental analysis (SEM/EDAX), including the examination of Ca, Al, Cr, V, Cu, Fe, S, Sr, Si, Ba, Pb, P, Mn, Rb, K, Ti, and Zn. The results showed that burning lump charcoal had toxicity indexes ranging from 2.5 to 5, primarily due to NOx emissions. Briquettes, on the other hand, exhibited higher toxicity indices between 3.5 and 6.0, with CO2 being the main contributor to toxicity. The average 24-h CO content of all charcoal samples exceeded the World Health Organization’s 24-h Air Quality Guideline of 6.34 ppm, with a measurement of 37 ppm. The data indicates that most of the products tested did not meet the prevailing quality standard (EN 1860-2:2005 (E) in Appliances, solid fuels and firelighters for barbecuing—Part 2: Barbecue charcoal and barbecue charcoal briquettes—Requirements and test method, 2005), which specifies a maximum of 1% contaminants, with some products containing as much as 21% impurities. The SEM analysis revealed irregularly shaped grains with an uneven distribution of particles, and the average particle size distribution is quite broad at 5 μm. Malaysia Charcoal had the highest calorific value at 32.80 MJ/Kg, with the value being influenced by the fixed carbon content—higher carbon content resulting in a higher calorific value. [ABSTRACT FROM AUTHOR]

The CH4 storage by adsorption on activated carbons for natural gas handling has gained interest due to the appearance of lightweight materials with large surface areas and pore volumes. Consequently, kinetic parameters estimation of the adsorptive process can play a crucial role in understanding and scaling up the system. Concerning its versatility, banana peel (BP) is a biomass with potential for obtaining different products, such as biochar, a solid residue from the biomass' thermal decomposition of difficult disposal, where through an activation process, the material porous features are taken advantage to application as adsorbent of gaseous substances. This research reported data for the CH4 adsorption kinetic modeling by biochar from BP pyrolysis. The activated biochar textural characterization showed particles with fine mesoporous structure (pore diameter ranging between 29.39 and 55.62 Å). Adsorption kinetic analysis indicated that a modified pseudo-first-order model was the most suitable to represent the experimental data, with equilibrium adsorption of 28 mg g−1 for the samples activated with 20.0% vol wt.−1 of H3PO4 and pyrolysis at 500 °C. The equilibrium constant was consistent with the Freundlich isotherm model, suggesting a physisorption mechanism, and led to a non-ideal, reversible, and not limited to monolayer CH4 adsorption. [ABSTRACT FROM AUTHOR]

Bamboo, the fastest-growing plant, has several unique characteristics that make it appropriate for diverse applications. It is low-cost, high-tensile, lightweight, flexible, durable, and capable of proliferating even in ineffectual areas (e.g., incline). This review discusses the unique properties of bamboo for making charcoal and biochar for diverse applications. To produce bamboo charcoal and biochar, this study reports on the pyrolysis process for the thermal degradation of organic materials in an oxygen-depleted atmosphere under a specific temperature. This is an alternative method for turning waste biomass into products with additional value, such as biochar. Due to various advantages, bamboo charcoal is preferred over regular charcoal as it has four times the absorption rate and ten times more surface area reported. According to the reports, the charcoal yield ranges from 24.60 to 74.27%. Bamboo chopsticks were the most useful source for producing charcoal, with a high yield of 74.27% at 300 °C in nitrogen, but the thorny bamboo species have a tremendous amount of minimal charcoal, i.e., 24.60%. The reported biochar from bamboo yield ranges from 32 to 80%. The most extensive biochar production is produced by the bamboo D. giganteus, which yields 80% biochar at 300 °C. Dry bamboo stalks at 400 °C produced 32% biochar. One of the sections highlights biochar as a sustainable solution for plastic trash management produced during the COVID-19 pandemic. Another section is dedicated to the knowledge enhancement about the broad application spectrum of the charcoal and biochar. The last section highlights the conclusions, future perspectives, and recommendations on the charcoal and biochar derived from bamboo. [ABSTRACT FROM AUTHOR]

A method for obtaining effervescent tablets, consisting of magnetic carbon, tartaric acid, sodium carbonate and sodium bicarbonate, and their use for the adsorption of dichlorophenoxycarboxylic acids (DCPA)—2,4-dichlorophenoxyacetic, 2,4-dichlorophenoxypropionic and 2,4-dichlorophenoxybutyric acids and their metabolites—2,4-dichlorophenol and 4-chlorophenol is proposed. The tablets are immersed in an analyzed solution with a neutral reaction medium. To analyze soils, extraction with an alkali solution followed by the neutralization of the extract is carried out. After CO2 separation is completed, the sorbent is removed with a neodymium magnet and the analytes are desorbed with acetone. The acetone extract is evaporated under a stream of nitrogen, and the concentrate is analyzed by gas chromatography–mass spectrometry. The method was tested on model systems—samples of river water and typical chernozem, which were artificially contaminated with DCPA and chlorophenols (CP). In analyzing river waters, the limits of determination for DCPA are 0.7–0.9 μg/L, for CP—40 ng/L. In soils, the limit of detection is 3–4 and 0.1 μg/kg for DCPA and CP, respectively. [ABSTRACT FROM AUTHOR]

Tolerance gaps in wood connections are unavoidable, for reasons of constructability and the effects of natural shrinkage in timber elements with changing moisture content. During a fire, these gaps may lead to a substantial heat transfer to the metal connectors that are considered heat protected being embedded by the wooden components of the connection. Aluminium connectors are popular due to their ease of production and assembly, but they are particularly vulnerable to elevated temperatures. This study investigates the effects of tolerance gaps on the fire performance of aluminium connectors in beam-to-column/wall shear connections. Reduced-scale experiments were designed to study the temperature evolution of aluminium connectors during standard fire exposure for 1 mm and 6 mm tolerance gaps, as well the mitigation effects of additional intumescent fire protection in a 6 mm tolerance gap connection. For the 6 mm gap, the temperature of the connector increased much faster, reaching 286 ± 36°C after 80 min, at which time the connector with a 1 mm gap had only reached 97 ± 1°C. The addition of intumescent protection in a 6 mm gap case led to lower temperatures in the connection, in comparison to an equivalent tolerance gap without protection. Subsequently, two additional loaded fire tests were performed, for 6 mm and 22 mm tolerance gaps without fire protection, to investigate the critical failure mode of the connectors. In these cases, the failure occurred in the connectors at 87 min and 32 min, respectively, when their average temperatures reached approximately 315°C. This study demonstrates the critical influence of gap size on the fire performance of aluminium-wood joints. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of activated charcoal on the single-dose pharmacokinetics of mavacamten when administered 2 h or 6 h after mavacamten dosing. Methods: In this open-label, randomized, parallel-group study, healthy adults were randomized into three groups to receive mavacamten 15 mg alone or mavacamten 15 mg plus activated charcoal 50 g administered either 2 h or 6 h after mavacamten dosing. Pharmacokinetic parameters were derived from plasma concentration–time data using noncompartmental methods. Results: Of the 45 participants randomized, 37 completed the study. When activated charcoal was administered 2 h after mavacamten dosing, mavacamten absorption and exposure were reduced compared with when mavacamten was administered alone: the area under the concentration–time curve from 0 to 72 h (AUC0–72) and area under the concentration–time curve from time 0 extrapolated to infinity (AUCINF) were reduced by 14% and 34%, respectively. The maximum plasma concentration (Cmax) was also slightly lower when activated charcoal was administered 2 h after mavacamten dosing than with mavacamten alone. Pharmacokinetic profiles were similar for mavacamten alone and mavacamten plus activated charcoal administered 6 h after mavacamten dosing. Conclusions: Activated charcoal was successful in reducing mavacamten absorption and exposure when administered as soon as possible after identification of a need for adsorption (2 h after mavacamten dosing). No change in exposure was observed when activated charcoal was administered 6 h after mavacamten dosing. Clinical Trial Registration: NCT05320094 [ABSTRACT FROM AUTHOR]

Polypropylene has a wide range of applications in scientific research, industry, and production due to its excellent mechanical properties and chemical stability. However, owing to its low melt strength, inferior dimensional stability, and poor thermal stability, thus limiting its further application. Addressing this challenge, a series of polymer composites consisting of rice husk charcoal (RHC), modified using 3-glycidyloxypropyltrimethoxysilane (KH560) as the silane coupling agent, and polypropylene (PP) have been fabricated by virtue of a melt blending process by us. Thermal behaviour, crystallization properties, mechanical properties, dimensional stability and microscopic morphology of PP/RHC composites are studied in detail. The results show that, when 20% modified RHC was added to the composites, it increased the initial decomposition temperature of PP by 130℃, which represents that we manufactured PP composites with better thermal properties by simple processing. The rheological performance tests showed that the addition of RHC increased the stiffness and dimensional stability of the composites, which is more conducive to the processing and moulding of the material. SEM indicated that KH560 can increase the compatibility of RHC with PP substrate, thus improving the performance of conforming materials. [ABSTRACT FROM AUTHOR]

The reduction of hematite present in the oxidized Fe-Ti-V ore to magnetite was carried out to use this ore in existing processes. One of the first steps in obtaining vanadium is the magnetic separation process, and the oxidized ore exhibits no magnetism. The creation of a reducing atmosphere using air and charcoal at four temperatures (400–700°C) was studied, resulting in an economically viable industrial process. Efficient reduction of hematite to magnetite was achieved at 400°C within 3 h. ICP OES determined the percentage of V 0.40%. After reduction, XRD showed that the entire hematite fraction became magnetite. The experimental data for kinetics were the first-order model, obtaining the apparent activation energy value equal to 15.8 kJ mol−1 and the pre-exponential coefficient equal to 0.49 min−1. Magnetic separation in a low-intensity field, 1500 G, of the reduced ore generated two fractions, the magnetic fraction, which concentrated 90.7% of the V present in the oxidized Fe-Ti-V ore, and the non-magnetic fraction with ilmenite (FeTiO3) and rutile (TiO2). It is important that it does not form vanadium carbide (VC) during the reduction of the ore. Vanadium ore can now be used in the process already applied in industry. [ABSTRACT FROM AUTHOR]

The extraction of valuables from waste has gained momentum. Thermal influence alters both the organic and inorganic components of coal. Insufficient knowledge on the association of rare earth elements (REEs) with the parent matrix of thermally altered high-ash coals (63% ash) limits the potential for such coals being utilized for isolation of valuables. In this study, we analyzed the distribution and occurrence modes of REEs within a magmatically altered high-ash coal via nine-step sequential extraction, combining Tessier and BCR methods. The total concentration of REEs in the coal sample, on whole coal basis, was found to be 820 ppm, which is significantly higher than the world average. Major mineral oxides were deduced to be those of Si, Fe, Al, Ca, Mg, and Ti. Sequential extraction confirmed that about 66% of HREE and 25% of LREE were included in the residual fraction. LREEs were concluded to be primarily in ionic form, whereas HREEs were speculated to be associated with the TiO2 phase. XRD analyses showed that thermal alteration affected the dolomite phase specifically, which selectively got removed where carbonate-bound elements were assessed. Petrographic analysis supported the magmatic influence and demonstrated the presence of mosaic structures and pores containing unfused vitrinite, with a reflectance value of 3.6. To summarize, the present study pertaining to delineation of association of valuables in high-ash heat-altered coals from an Eastern coalfield in India can potentially open up new avenues for utilizing such coals, which are otherwise considered waste. Article Highlights: A nine-step sequential chemical leaching process employing eco-friendly lixiviants was implemented to delineate the mineralogical associations in high-ash heat altered coal of Indian origin. Dolomite was completely eradicated at the complexation stage implying alteration of this mineral phase due to magmatic influence. LREEs were concluded to be present primarily in the ionic form while HREEs were strongly associated with anatase phase. Petrographic analysis revealed presence of mosaic structures with porous morphology containing un-fused vitrinite. [ABSTRACT FROM AUTHOR]

This paper presents a scalable ultra-rich carbonization process in counter-current packed bed (CCPB) for synthesizing biochar/charcoal with a yield of more than 33% and fuel consumption rate of more than 200 g/m2s (which is at least 2 times more than the maximum achievable with conventional gasification) from coconut shells (CS). The novelty of the process lies in the use of reactant pre-heating to slightly below the devolatilization temperature of CS as a strategy to achieve steady and controlled conversion of CS to biochar/charcoal. The basis for this idea is that the ignition time (tig) of biomass particles decreases significantly with pre-heating while the time for devolatilization (tv) remains more or less the same. Single particle experiments with CS as fuel and atmospheric air as oxidizer show that tv/tig increases from 1.3 to 7.7 with a corresponding increase in pre-heating temperature Ti from 30 to 170 ∘C. The bed operation, in terms of flame propagation, equivalence ratio, and charcoal yield, with pre-heating to slightly below devolatilization temperature in CCPB systems, shows several interesting behaviors not observed in traditional gasifier systems. Two prominent examples of such behaviors are steady flame propagation under extremely rich conditions (volatile equivalence ratio, ϕv > 10) and reduction in peak bed temperature (Tpb) well below 600 ∘C. The biochar yield of the developed process is at least ∼ 25% more than traditional CCPB gasification system. The feedstock flexibility, self-sustainability, and scalability of the developed process are also brought out. [ABSTRACT FROM AUTHOR]

As promising energy-storage devices, zinc–air batteries (ZABs) exhibit slow reaction kinetics for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurring at their electrodes. High-performance bifunctional catalysts must thus be synthesized to accelerate the reversible conversion of oxygen and improve the rate and overall performance of ZABs. Herein, we reported the promising prospects of self-supported composite electrodes composed of wood-derived carbon (WDC) and bimetallic cobalt-iron alloys/oxides (CoFe-CoFe2O4@WDC) as efficient electrocatalysts for alkaline ORR/OER. WDC provided a favorable three-phase interface for heterogeneous reactions owing to its layered porous structure and genetic stability, thereby enabling mass diffusion and improving reaction kinetics. The CoFe2O4 spinel surface was reduced to bimetallic CoFe alloy to form abundant heterostructure interfaces that promote electron transfer. Under alkaline conditions, the optimized composite electrode exhibited a remarkable high half-wave potential of 0.85 V and an exceptionally low overpotential of 1.49 V. It also exhibited stable performance over an impressive 2340 cycles in a ZAB. Theoretical calculations also confirmed that the heterointerface addresses the issue of proton scarcity throughout the reaction and actively facilitates the creation of O–O bonds during the reversible transformation of oxygen. This study introduces a new concept for developing bifunctional and efficient electrocatalysts based on charcoal and encourages the sustainable and high-value use of forest biomass resources. Highlights: Water dissociation was regulated to provide proton for smooth response under alkaline conditions and accelerate the conversion of *O2 to *OOH. The alloy surface formed CoFe oxyhydroxide in the OER voltage range, and the adsorption capacity of intermediates was adjusted to facilitate O–O bond formation. The d-band center moved downward due to interface electron interaction, modifying the binding ability of intermediates. [ABSTRACT FROM AUTHOR]

Although addition of pyrolyzed organic materials (biochars) to soil generally results in increased growth and physiological performance of plants, neutral and negative responses have also commonly been detected. Toxicity of organic compounds generated during pyrolysis, sorbed by biochars, and then released into the soil solution, has been implicated as a possible mechanism for such negative effects. Conversely, water-soluble biochar constituents have also been suggested to have "hormetic" effects (positive effects on plants at low concentrations); however, no specific compounds responsible have been identified. We investigated the relative phytotoxicity—and possible hormetic effects—of 14 organic compounds common in aqueous extracts of freshly produced lignocellulosic biochars, using seed germination bioassays. Of the compounds examined, volatile fatty acids (VFAs: acetic, propionic, butyric, valeric, caproic, and 2-ethylbutyric acids) and phenol, showed acute phytotoxicity, with germination-based ED50 values of 1–30 mmol L−1, and 2-ethylbutyric acid showed ED50 values of 0.1–1.0 mmol L−1. Other compounds (benzene, benzoic acid, butanone, methyl salicylate, toluene, and 2,4-di-tert-butylphenol) showed toxic effects only at high concentrations close to solubility limits. Although phytotoxic at high concentrations, valeric and caproic acid also showed detectable hormetic effects on seedlings, increasing radicle extension by 5–15% at concentrations of ~ 0.01–0.1 mmol L−1. These data support the hypothesis that VFAs are the main agents responsible for phytotoxic effects of lignocellulosic biochar leachates, but that certain VFAs also have hormetic effects at low concentrations and may contribute to positive effects of biochar leachates on early plant development in some cases. Highlights: 151 compounds were identified in leachates from 13 biochars. Among common compounds, volatile fatty acids (VFAs) and phenol showed the most pronounced phytotoxic effects. Some VFAs also had hormetic effects, enhancing radicle extension growth at low concentrations. Effects were consistent among test plant species but the smallest-seeded species showed the highest sensitivity. [ABSTRACT FROM AUTHOR]

To prevent the spread of pine wilt disease (PWD), a transportable carbonization equipment was designed for in-situ treatment of infected pine wood (IPW). The equipment killed all pine wood nematodes (PWNs) in IPW when carbonization temperature was up to 200 °C. The optimal laboratory process of infected pine wood charcoal (IPWC) was carbonization temperature of 500 °C, heating rate of 3 °C min−1 and holding time of 0 min. Based on the optimal laboratory process, the transportable carbonization equipment produced IPWC with a fixed carbon content of 79.82%, and ash content of 1.14% and a moisture content of 7.83%, which meets the requirements of EN 1860-2:2005(E) standard. The economic efficiency of incineration (T1 mode), crushing (T2 mode), and transportable carbonization (T3 mode) was evaluated. For each ton of IPW treatment, the profit generated was −75.48 USD in T1 mode, 26.28 USD in T2 mode, and 51.91 USD in T3 mode. T3 mode had the highest economic efficiency. These findings will be helpful to provide guidance for the control of PWD and value-added utilization of IPW. Highlights: A transportable carbonization equipment was designed for in-situ treatment of IPWs The transportable carbonization equipment killed all PWNs of IPW when carbonization temperature was up to 200 °C. In the transportable carbonization mode, the income generated from treating each ton of IPW was 51.91 USD. [ABSTRACT FROM AUTHOR]

Primary studies of the concentrations of rare elements in the sediments of two lakes on King George Island (Kitezh and Glubokoe) showed that their geochemistry reflects the geological features of the area. Compared to the composition of the upper part of the Earth's crust, the studied sediments are enriched in Cu, Cd, V, Tl, Mn, Ti, and P. Similar patterns have been identified in the geochemistry of volcanic and sedimentary rocks of the Fildes Peninsula. Trends in REE changes generally follow their behavior in rocks, but the overall REE concentration in sediments of lakes is higher, which may be due to the presence of organic matter accumulating in sediments of water bodies. Unlike the aquatic environment, the chemical composition of sediments does not reflect the significant influence of the activities of polar stations. However, small increases in Pb and Sb concentrations in the upper sediments suggest the influence of long–range atmospheric transport of the contaminants. [ABSTRACT FROM AUTHOR]

Charcoal is a common material for radiocarbon dating. Meanwhile, it is underestimated as an object of dendrochronological analysis used to date natural and historical–archaeological events with an accuracy of up to a year. The new approach to charcoal sample preparation developed by the authors makes it possible to remove previous restrictions on this fragile material imposed in the dendrochronological studies and to use it as an efficient information source in paleoecology, paleoclimatology, paleogeography, and archaeology. This new method has been applied to construct a 377-year tree-ring chronology using archaeological charcoals from ancient iron-smelting furnaces in the Chuya–Kurai ferrous metallurgy province of the Russian Altai. This tree-ring chronology of charcoal is the first in Russia and the longest in dendrochronological practice throughout the world. Further analysis will provide new information on the nature and archaeological events of the high-mountain region located in the center of Eurasia. [ABSTRACT FROM AUTHOR]

Purpose: Biochar, as a stable carbon-rich material, has received concentrated attention in soil quality improvement, especially in soil carbon sequestration. This study aimed to find out the effects of biochar application on carbon stock in the whole salt-affected soil ecosystems. Methods: This study was conducted in a heavy salt-affected soil, aiming at investigating biochar application effects on salt-affected soil organic carbon (SOC), soil inorganic carbon (SIC), as well as plant (Tamarisk chinensis) biomass carbon stocks. Results: After 4 years of biochar application of 30, 60, and 90 t ha−1, the results showed that biochar increased soil total organic carbon (STOC) stock by 54.78, 160.44, and 198.33%, and biochar increased soil total inorganic carbon (STIC) stock by 13.85, 11.04, and 16.03%, respectively. Further, it is calculated that biochar increased native SOC (extra SOC excluding biochar carbon) by 7.63, 66.15, and 56.90% and SIC by 13.55, 10.44, and 15.12%, respectively. In addition, biochar application accelerated Tamarisk chinensis growth by 10.03, 23.54, and 11.28%, respectively. Combining all the SOC, SIC, and plant-derived carbon, it is concluded that biochar application enlarged salt-affected soil-vegetation ecosystem carbon stock by 23.36, 47.80, and 58.10%, respectively. Conclusion: These results indicated that applying biochar in salt-affected soil can enhance salt-affected soil-vegetation ecosystem carbon stocks. The mechanisms behind this phenomenon may be that biochar improves soil water content and bulk density, which promotes Tamarisk chinensis growth. Biochar has a good potential to improve salt-affected soil quality and mitigate climate change. [ABSTRACT FROM AUTHOR]

The Florida Everglades are a vast subtropical wetland that historically spanned over 1,000,000 hectares, but much of the Everglades has changed in the last 100 years due to anthropogenic activity. Collier County, situated in southwest FL and bordering the Gulf of Mexico, was subject to alteration in the form of logging, road building, and canal digging. These actions disrupted the natural sheet flow of water and had large environmental impacts on the region, impacts which are slowly being addressed by Everglades restoration efforts. The aim of this work was to observe environmental change at a cypress swamp forest in Collier County within the Big Cypress National Preserve. Using sediment core data including charcoal analysis, loss on ignition, and peat humification, as well as remote sensing techniques, this project uses a novel approach to assess local environmental conditions in the modern era for the region. While this analysis was based on a single core located at the study site, additional ground-penetrating radar profiles at the study site showed a consistent, laterally continuous distribution of subsurface interfaces, therefore suggesting that the core is representative of the conditions at this specific location. Historical records and contemporary data are used to evaluate environmental change over time, and satellite imagery is used to quantify vegetation health. Environmental change related to anthropogenic activity is noted, and evidence of progress from restoration efforts is observed from the last two decades in our study's data. [ABSTRACT FROM AUTHOR]

This study involved the production of 20 biochar samples derived from secondary medicinal residues of Snow Lotus Oral Liquid, processed within the temperature range of 200–600 °C. Additionally, four medicinal residues, including dissolved organic matter (DOM), from 24 samples obtained using the shaking method, served as the primary source material. The investigation focused on two key factors: the modifier and preparation temperature. These factors were examined to elucidate the spectral characteristics and chemical properties of the pharmaceutical residues, biochar, and DOM. To analyze the alterations in the spectral attributes of biochar and medicinal residues, we employed near-infrared spectroscopy (NIR) in conjunction with Fourier-infrared one-dimensional and two-dimensional correlation spectroscopy. These findings revealed that modifiers enhanced the aromaticity of biochar, and the influence of preparation temperature on biochar was diminished. This observation indicates the stability of the aromatic functional group structure. Comparative analysis indicated that Na2CO3 had a more pronounced structural effect on biochar, which is consistent with its adsorption properties. Furthermore, we utilized the fluorescence indices from UV–visible spectroscopy and excitation-emission-matrix spectra with the PARAFAC model to elucidate the characteristics of the fluorescence components in the DOM released from the samples. The results demonstrated that the DOM released from biochar primarily originated externally. Aromaticity reduction and increased decay will enhance the ability of the biochar to bind pollutants. Those results confirmed the link between the substantial increase in the adsorption performance of the high-temperature modified charcoal in the previous study and the structural changes in the biochar. We investigated the structural changes of biochar and derivative DOM in the presence of two perturbing factors, modifier and preparation temperature. Suitable modifiers were selected. Preparation for the study of adsorption properties of snow lotus medicinal residues. [ABSTRACT FROM AUTHOR]

The function of tropical peatland as a carbon sink is a balance between peat accumulation and peat loss; however, various interacting factors are involved affecting this process. In this study, we collected and intensively radiocarbon dated peat cores from two peat domes, visualized their cross-sectional profiles of geochemical properties, and developed three macrocharcoal records from each peat dome. We find that the young (4500 y calBP) and shallow (6 m) coastal peat has a simple and linear age–depth relationship, showing stable accumulation of carbon during the late Holocene. In contrast, the older (ca. 40,000 y cal BP) and deeper (15 m) inland peat shows a more complex history, where we observed age reversals and hiatuses, likely caused by climate variability from the Last Glacial Maximum (LGM) to the Holocene. The charcoal record reveals a continuous presence of low-severity fire as indicated by charcoal morphotypes, though fire frequency increased after agriculture was established. An age reversal during the LGM was likely caused by a flood. Two periods of hiatuses occurred, each several millennia in length, at the end of the LGM and during the early Holocene. One cause of the hiatuses may have been a climatically halted peat formation from low precipitation and cooler climate during the LGM. Another cause may have been that severe fires consumed thousands of years of accumulated peat. If the hiatuses were entirely due to fire, the carbon released from these paleo-fire events (600 t C ha−1) suggests several times the impact of the most intense modern peat fires. [ABSTRACT FROM AUTHOR]

The article presents a technique for obtaining advanced layered radio-absorbing materials based on powdered charcoal. The technique includes the following technologies: incorporation of the electrolyte aqueous solution into the material particles pores and adhesive pressing. The developed technique is more manufacturable compared to its analogs. Materials obtained in accordance with this technique are characterized by flexibility, as well as lower cost compared to other carbon-containing radio-absorbing materials. The experimental characteristics of electromagnetic radiation reflection and transmission coefficients in the frequency range 2.0–17.0 GHz of the materials obtained in accordance with the developed technique are described. The results of the comparative analysis of these characteristics are provided. On the basis of these results, it is determined that the average values of electromagnetic radiation reflection coefficient in the specified frequency range of the materials based on powdered nonactivated wood charcoal, powdered activated wood charcoal, and powdered activated coconut charcoal are –4.5, –8.5, and –9.0 dB (when these materials fixed on metal reflectors). The average values of their electromagnetic radiation transmission coefficient are –11.5, –20.0, and –15.5 dB respectively. The investigated materials seem to be promising for use in order to protect electronic equipment from external electromagnetic interference. [ABSTRACT FROM AUTHOR]

Fire-derived charcoal (charcoal) is a stable byproduct of forest fires, which accumulates in the litter layer and soils of boreal forests. Therefore, the decomposition of litter and roots as one of the key processes in the carbon cycle in the soils of northern forests proceeds almost everywhere in the presence of charcoal. To date, the data on the influence of charcoal on the organic material decomposition in boreal forests are extremely scarce and most of them do not consider the cold period, which lasts on the average half a year in this zone. The goal of this work is to determine the seasonal influence of charcoal on the decomposition of plant litter of different qualities (larch needles, birch leaves, grasses, and mixtures of these litter types) on the soil surface and the roots of the same types in the soil. A field litterbag experiment demonstrates that charcoal accelerates the decomposition of litter in a species-specific manner. Charcoal accelerates the mass loss of recalcitrant aboveground litter (needles) and all types of roots during the cold season. As for the warm season, charcoal accelerates the decomposition of only needles and has no effect on the roots. Thus, our study shows a greater influence of charcoal on the subsoil decomposition especially in the cold season. The seasonal influence of charcoal is demonstrated for the first time and should be taken into account as an important factor of humus formation and carbon dynamics in the soils of boreal forests. [ABSTRACT FROM AUTHOR]

Scientific information on the ash quality of Tachigalis vulgaris wood may reveal nutrient export mechanisms in energy forests and also insights into the wood quality for thermochemical conversions. This study aimed to evaluate the nutrient export and technological implications of ashes in the combustion of T. vulgaris grown in different planting spacings (4.5 m2;6.0 m2; 7.5 m2; 9 m2; 10.5 m2; 12.0 m2). The levels of inorganic elements were determined for 7-year-old trees cultivated in experimental plantations across the eastern Amazonia region. The element contents were used to obtain the export of nutrients and to calculate the fouling index (FI), basic to acidic compound ratio (B/A), sintering index (SI), slag viscosity index (SR), bed agglomeration index (BAI), and alkali index (AI). The most exported nutrients were Ca (18.7 kg/ha), P (13.9 kg/ha), and K (6.6 kg/ha). The FI, B/A, SI, and SR indices suggested deposition problems in the boilers for all planting spacings. However, BAI and AI indicated a low propensity to form fouling and slag. The spacing significantly influenced the P export. Planting spacing of 12 m2 demands increased P fertilization to maintain plantation productivity. The low ratio between alkaline earth and alkaline elements and high P2O5 values in the ash of T. vulgaris are disadvantageous. However, the high Al2O3 level and low ash content may contribute to the increase in the melting temperature of the ash. The study revealed that Tachigali vulgaris is a suitable species for wood production in energy forests. [ABSTRACT FROM AUTHOR]

Porous ceramic compound as adsorbents for heavy metal removal was produced by mixing kaolin with charcoal in addition to cobalt ferrite nanoparticles at 0, 3, 5, 7, and 10 wt%. The synthesized magnetic cobalt ferrites, prepared using sol–gel auto-combustion method, were characterized by X-ray diffraction, field emission scanning electron microscopy, and vibrating sample magnetometer, as well as examining the physical and mechanical characteristics of the kaolin/cobalt ferrite composite. PH and adsorbent dose were studied in the context of the adsorption of Pb2+, with a comparison of results against using crushed kaolin/CoFe2O4 powder. The resulting CoFe2O4 nanoparticles have saturation magnetization values of about 48.85 emu/g. Darcy permeability of the porous ceramics prepared by the semi-dry pressing method was increased from 1.9 to 4.6 cm/s; meanwhile, for porous ceramics prepared by the slip casting method, the permeability varied from 5 to 7.9 cm/s. Utilizing kaolin/CoFe2O4 particles, the best removal efficiency for Pb2 + was found to be 100% at pH 3 used 10 wt% of Co-ferrite for samples prepared by slip casting method and 91.9% for samples prepared by semi-dry method. In contrast, the best lead removal efficiency of 89.6% was reported at pH 5 when utilizing crushed kaolin/CoFe2O4 powder, and the removal efficiency increased at high concentrations of lead ions from 16.7 to 96.68%, with the highest adsorption of lead ions obtained at 50 min, reaching a removal efficiency of 83.23%. [ABSTRACT FROM AUTHOR]

Wood is exposed to different atmospheric conditions in the production of charcoal due to the occurrence of rainfall and variation in relative humidity. However, there is a lack of scientific information related to charcoal hygroscopicity and desorption capacity depending on water content. Thus, in the present study, we analyzed the influence of carbonization temperature in brick kilns on the hygroscopic capacity of charcoal from a 7-year-old Eucalyptus sp. wood. Charcoal was produced at final temperatures of 340, 380, 420, and 460 °C. Raman spectroscopy, Fourier-transform infrared absorption spectroscopy, scanning electron microscopy, and surface area measurement were performed to identify structural changes in charcoal. The charcoal samples were exposed to six different saline solutions to simulate the relative humidity of the environment, ranging from 33 to 98%, for the determination of the moisture adsorption capacity. The charcoal surface area values ranged from 7.9 (340 °C) to 12.3 m2 g−1 (460 °C). Charcoal porosity increased by 14.4% with increasing temperature. The adsorption capacity decreased with the rising final carbonization temperature. An average reduction of 9.9% between the moisture adsorbed by the charcoal samples produced at 340 °C and 460 °C was observed. The increase in surface area and porosity of charcoal as a function of temperature resulted in the loss of environmental moisture adsorption capacity due to the removal of carboxyl and hydroxyl groups in the temperature range analyzed. Physical mechanisms were more relevant in the water–charcoal relationship, which can directly influence the drying process of the bioreducer in stockyards. [ABSTRACT FROM AUTHOR]

To investigate the effect of Fe-addition on the Cs+-adsorption ability (Cs+-AA) of woody charcoal, charcoal samples were prepared from Japanese cedar (JC) and Japanese oak (JO) wood impregnated with Fe3+ at 600 and 800 °C. The residual functional groups of the charcoal samples were examined using infrared-photoacoustic spectroscopy. OH groups were observed in the charcoal made at 600 °C, and no vibrational bands were detectable in the charcoal synthesized at 800 °C. The observation of Raman D-, G-, and G´-bands revealed that all charcoal samples contained sp2-carbon atoms but graphitization occurred only in the iron-loaded charcoal made at 800 °C. The Cs+-AA of the JC and JO charcoal samples were evaluated based on the adsorption isotherms of an aqueous CsCl (Cs+: 33 mg/L) solution. The addition of Fe3+ to wood had a negative effect on the Cs+-AA of the JO charcoal made at 600 °C, but a positive effect on the Cs+-AA of the JC charcoal prepared at 800 °C. [ABSTRACT FROM AUTHOR]

The high gas temperatures and oxygen pressures in the turbine of oxygen-rich turbomachinery put conventional engineering alloys such as IN718 at risk of particle impact ignition, i.e., metal fires initiated when particulate strikes a solid surface. The standard model of particle impact ignition assumes that the impacting particle must first ignite in order to kindle to the target material. Here, we invalidate this belief through particle impact ignition experiments which show that IN718 can ignite when struck by inert Al2O3 particles with supersonic impact velocities. Through post-mortem analysis of non-ignited samples, we find that subsonic particle impact causes minimal crater damage whereas supersonic particle impact leaves extensive crater plasticity and pileup, with evidence of molten ejecta near the impact site. Complementary finite element simulations of supersonic impact events confirm extreme adiabatic heating and localized melting. These findings demonstrate that particle impact can drive target ignition even in the absence of particle burning provided the thermal excursion at impact exceeds the melting point of the target material. [ABSTRACT FROM AUTHOR]

Background: Monkshood, a toxic plant containing a potent cardio- and neurotoxin called aconitine, can lead to a range of symptoms, including nausea, vomiting, dizziness, seizures, and cardiac arrhythmias. Mortality associated with this intoxication are due to ventricular tachyarrhythmias which are difficult to treat and often refractory in nature. Case presentation: We present a case of a 17-year-old female patient who presented to the emergency department after intentionally ingesting a monkshood plant and developed atrioventricular dissociation and frequent ventricular ectopy. The patient was successfully treated with activated charcoal, supportive care, and cardiac monitoring. Conclusion: This case highlights the importance of early recognition of aconitine poisoning and the need for prompt supportive care, cardiac rhythm monitoring, and preemptive antiarrhythmic treatment planning. [ABSTRACT FROM AUTHOR]

I synthesize the anthracological data from archaeological sites located north of Mendoza, in central-western Argentina, to demonstrate the potential of anthracology for studying socio-environmental relationships. My methodology includes archaeological, historical, ethnographic, and environmental data from 1200 to 100 years BP - the pre-Hispanic, colonial, and modern periods. For each period, I discuss the characteristics of four interrelated factors: (1) ways of dwellings, (2) socio-environmental relationships, (3) archaeological records on firewood use, and (4) human-induced landscape modifications. My results allow the identification of problems and the generation of questions that enrich the social interpretation of the anthracological record. [ABSTRACT FROM AUTHOR]

The recycling of heavy metals contained in alkaline batteries allows minimizing the environmental impact and gives an alternative use to this waste, which can be used in the pyrometallurgical industry. In the present research work, we evaluated the possibility of reducing the manganese oxide black mass from discarded alkaline batteries to produce metallic manganese, using charcoal as a reducing agent. The procedure begins with the characterization of the raw materials, the stoichiometric calculations and the preparation of a practical method to produce self-reducing pellets, composed of manganiferous material, charcoal and bentonite as agglomerant. Computer simulations were performed, to establish the appropriate thermodynamic conditions for reduction. The tests were carried out in a tubular-type furnace, and the results obtained were evaluated using optical microscopy, scanning electron microscopy coupled with microchemical analyses and X-ray diffraction techniques. It was verified that the agglomerates showed a self-reducing behavior, so an increase of the %Mn in the samples due to increasing the temperature of the reduction treatment was found, as well as the presence of a metallic manganese phase that was identified by X-ray diffraction analysis. Flow sheet for the production of self-reducing pellets containing eucalyptus charcoal for the recycling of manganese contained in spent alkaline batteries [ABSTRACT FROM AUTHOR]

Charcoal production stemming from small-scale Eucalyptus camaldulensis plantations has brought about significant socio-economic benefits and improved livelihoods in Ethiopia. Nevertheless, the current practice involves the use of traditional earth mound kilns, leading to inefficiencies, reduced charcoal income, and environmental pollution. This research aims to assess charcoal conversion efficiency, perform a cost–benefit analysis, and measure gas emissions from improved charcoal-making kilns sourced from Eucalyptus camaldulensis small-scale plantations in comparison to traditional earth mound kilns in northwestern Ethiopia. A one-way analysis of variance (ANOVA) was executed, with a significance level set at 0.05. The study results indicate a significant (P < 0.001) disparity in charcoal conversion efficiency across the various tested kilns, with the ranking as follows: Green mad retort kiln (33.7%) > Casamance kiln (32.09%) > MRV steel kiln (28.25%) > traditional earth mound kilns (23.55%). The improved charcoal-making kilns enhanced wood-to-charcoal conversion efficiency by 20–43% compared to traditional earth mound kilns. In terms of financial viability, Casamance improved kilns generated the highest equivalent annual charcoal income (117,126.9 ETB/year), followed by Green Mad Retort (82,893.8 ETB/year) and MRV steel kilns (58,495.9 ETB/year). As anticipated, traditional earth mound kilns yielded the lowest net present value (47,304.3 ETB/year). Traditional earth mound kilns also exhibited significantly longer carbonization times (P < 0.001), taking 3.6 times longer than the Mark V kiln and 2 times longer than the Casamance kiln. Furthermore, the statistical analysis demonstrated that improved charcoal-making technology reduced carbon dioxide (CO2) emissions by 36.1–50.7%, carbon monoxide (CO) emissions by 39.2–54.3%, and methane (CH4) emissions by 29.6–47%. In conclusion, the use of improved charcoal-making kilns has demonstrated significant enhancements in charcoal conversion efficiency, charcoal income, and environmental sustainability. Given these positive outcomes, we strongly recommend a decisive transition from traditional to cleaner, sustainable, and less emissions-intensive charcoal making kilns. [ABSTRACT FROM AUTHOR]

Sulfur-containing gases are main sources of landfill odors, which has become a big issue for pollution to environment and human health. Biocover is promising for treating landfill odors, with advantages of durability and environmental friendliness. In this study, charcoal sludge compost was utilized as the main effective component of a novel alternative landfill cover and the in situ control of sulfur-containing odors from municipal solid waste landfilling process was simulated under nine different operating conditions. Results showed that five sulfur-containing odors (hydrogen sulfide, H2S; methyl mercaptan, CH3SH; dimethyl sulfide, CH3SCH3; ethylmercaptan, CH3CH2SH; carbon disulfide, CS2) were monitored and removed by the biocover, with the highest removal efficiencies of 77.18% for H2S, 87.36% for CH3SH, and 92.19% for CH3SCH3 in reactor 8#, and 95.94% for CH3CH2SH and 94.44% for CS2 in reactor 3#. The orthogonal experiment showed that the factors influencing the removal efficiencies of sulfur-containing odors were ranked from high to low as follows: temperature > weight ratio > humidity content. The combination of parameters of 20% weight ratio, 25°C temperature, and 30% water content was more recommended based on the consideration of the removal efficiencies and economic benefits. The mechanisms of sulfur conversion inside biocover were analyzed. Most organic sulfur was firstly degraded to reduced sulfides or element sulfur, and then oxidized to sulfate which could be stable in the layer as the final state. In this process, sulfur-oxidizing bacteria play a great role, and the distribution of them in reactor 1#, 5#, and 8# was specifically monitored. Bradyrhizobiaceae and Rhodospirillaceae were the dominant species which can utilize sulfide as substance to produce sulfate and element sulfur, respectively. Based on the results of OUTs, the biodiversity of these sulfur-oxidizing bacteria, these microorganisms, was demonstrated to be affected by the different parameters. These results indicate that the novel alternative landfill cover modified with bamboo charcoal compost is effective in removing sulfur odors from landfills. Meanwhile, the findings have direct implications for addressing landfill odor problems through parameter adjustment. [ABSTRACT FROM AUTHOR]

Background: Bamboo charcoal has garnered wide recognition as an adsorbent owing to its stability and availability. Phosphoric acid modification contributes to forming specific functional groups on the surface of bamboo charcoal, culminating in the augmentation of its adsorption capabilities. Results: The modification process in this study involved impregnating the bamboo charcoal in a 45% mass fraction of phosphoric acid solution with a 1:10 ratio (bamboo charcoal powder to phosphoric acid), followed by activation at a temperature of 500 °C for a duration of 1.5 h. The modification resulted in the formation of hydroxyl, carboxyl, and phosphate groups on the surface of the bamboo charcoal. Furthermore, the specific surface area of the modified bamboo charcoal surged from 4.91 m2/g to 115.18 m2/g, the average aperture decreased from 7.15 nm to 1.99 nm, and the pore volume escalated by 6.5 times. On this basis, a comparison in the adsorption capability for chlorogenic acid, a natural small-molecule active ingredient, was drawn before and after the modification of bamboo charcoal. The results indicate that the modified bamboo charcoal showcases an impressive 46.8-fold increase in its adsorption capacity when juxtaposed with the unmodified bamboo charcoal. Through the calculations based on density functional theory (DFT), the addition of functional groups on the surface of the modified bamboo charcoal module allows for the formation of hydrogen bonds with the chlorogenic acid module, with the highest binding energy reaching − 57.59 kJ/mol. Conclusion: As evidenced by the adsorption kinetic studies, the curve of modified bamboo charcoal for chlorogenic acid abides by a first-order kinetic equation. Additionally, adsorption thermodynamic studies reveal that the curve of modified bamboo charcoal for chlorogenic acid conforms to the Boltzmann equation. These results shed light on the mechanism of selectively adsorbing specific constituents using phosphoric acid-modified bamboo charcoal, thereby providing a solid theoretical foundation for the application of bamboo charcoal. [ABSTRACT FROM AUTHOR]

With the rapid development of urbanization, the number of urban sewage treatment plants is increasing, wastewater treatment volume is gradually becoming large, and correspondingly, the sludge production capacity has a rapid growth. As a new method of sludge disposal, sludge carbonization is characterized by low energy consumption, simple products, and wide resource utilization prospects, which is of great help to solve problems of current sludge disposal in China. The residual sludge from sewage plant was used as raw material in this study in order to investigate the physical and chemical properties of sludge charcoal after high temperature carbonization and explore the enhancement in the removal of pollutants including CODcr, NH3-N, TN, and TP during sewage treatment with the used sludge charcoal. The results show that the optimal dosing amount of sludge charcoal was 2 g.L−1 when it was added into SBR equipment at one time, while the optimal dosing amount is 0.06 g.L−1 when it was added into SBR equipment with each influent process. The enhanced removal effect of pollutants in sewage treatment process mainly depended on the physical adsorption and intensified bio-degradation of sludge charcoal, and activated sludge and sludge charcoal were synergistic in water treatment. The removal effect of pollutants is strengthened in the physical adsorption—bio-degradation—sludge charcoal reproduction—re-adsorption system. These suggested that sludge charcoal could be promising for the enhancement of pollutant removal in sewage through activated sludge process. [ABSTRACT FROM AUTHOR]

Black carbon is also known as pyrogenic carbon formed by partial combustion of organic material under limited oxygen supply. It occurs along a continuum from original organic slightly charred material to highly aromatic combustion residues such as charcoal, graphite, and soot. Black carbon is extensively studied in various environments due to its ubiquity. It is also important for the biochar community because it can specifically trace the stable polycondensed part of biochar. Different methods have been adopted for black carbon determination; among them using benzene polycarboxylic acids (BPCA) as molecular markers for the polycondensed aromatic moieties of charred materials. However, different researchers have shown interferences from organic matter during BPCA analysis. Therefore, the aim of this work was to assess if artificial formation of BPCA occurs in soil samples when the organic carbon load exceeds 5–10 mg. For this purpose, we conducted black carbon analysis of different soil samples with varying TOC contents of up to 20 mg. In addition, organic matter-rich plant materials were used as a black carbon-free control (leaves of Ivy and Beech, leaves/needles of Spruce and needles of Thuja). To exclude the high-pressure digestion as source of artificial black carbon formation, a comparison between the conventional and a microwave-assisted extraction (MAE) oxidation process was included. Our results show that for soil samples, no artificial BPCA formation occurred at least up to 20 mg of total organic carbon. Higher sample weights are unrealistic for BPCA analysis of soils using current methodology. Therefore, our results clearly demonstrate that there is no artificial BPCA formation during properly performed black carbon analysis of soil samples. On the contrary, for some samples, BPCA contents tended to decrease with increasing sample weight, and thus increasing amount of TOC. In contrast, for plant samples, artificial BPCA formation of up to 3 g kg−1 occurred when more plant material equivalent to 10 mg total organic carbon was used. However, there was no amount dependence of artificial BPCA formation. The reason for artificial BPCA formation was not the high-pressure digestion, as microwave-assisted digestion showed comparable results. However, for real-world analysis, this artificial BPCA formation is not relevant because such high soil sample weights cannot be used. Nevertheless, when using organic-rich material such as peat and charred materials, the samples should contain less than 10 mg of total organic carbon. [ABSTRACT FROM AUTHOR]

We used pollen and charcoal analyses of sediments from two lakes at the southern end of Eleuthera Island, the Bahamas, to reconstruct vegetation and fire history over the past 5000 years. We obtained a 254-cm long sediment sequence from Shad Pond on the south end of Eleuthera near the coast. We obtained a 140-cm long sediment sequence from Duck Pond Blue Hole midway from either coast. Shad Pond sediment from 180 to 240 cm is fibrous peat dating from ~ 3800 to 4800 cal yr BP. The pollen spectrum in the peat is dominated by red mangrove (Rhizophora mangle) indicating the presence of a red mangrove swamp during this period. Duck Pond Blue Hole sediment from 100 to 140 cm is fine calcareous mud with only traces of pollen present. Palm pollen dominate the middle portion of both sediment sequences with pollen from rockland and coppice species also present. Palm pollen decline in both lakes ~ 1200 to 1300 cal yr BP, the start of Lucayan occupation. Palm pollen nearly disappear from Shad Pond sediments after ~ 1200 cal yr BP coincident with a spike in charcoal particles. Palm pollen drop by over one-half in Duck Pond Blue Hole after ~ 1200 cal yr BP, but there is only a small increase in charcoal particles. Palm pollen return in modest amounts toward the top of the Shad Pond sediments and there is a second, smaller peak in charcoal ~ 350 cal yr BP. This suggests a recovery of palms near the coast during the Plantation Period. Palm pollen gradually decline, charcoal increases, and pollen from disturbance species become very dominant toward the top of Duck Pond Blue Hole sediments after ~ 350 cal yr BP. The decline of palm pollen and increase in pollen from disturbance species in sediments from both sites ~ 1200 cal yr BP suggests heavy exploitation of palms by Lucayans, particularly near the coast. The later increase in charcoal and the significant increase in pollen from disturbance species in sediments from the inland Duck Pond Blue Hole site ~ 350 cal yr BP suggests inland land clearing during the Plantation Period. [ABSTRACT FROM AUTHOR]

Sedimentary records of environmental conditions retrieved from archeological sites provide valuable insight into the milieux of ancient humans and context to understand societal and cultural changes. At Jordan River Dureijat, an open-air site in Israel's Hula Valley documenting the entire Epipaleolithic period as well as the Early Neolithic, sediments exposed on the walls of the excavation pit reveal a sequence of lacustrine deposits accumulated continuously between c. 21.1 and 11.3 cal ka BP near the southeast margin of Paleolake Hula. Through sediment-grain-size, geochemical, and paleontological analyses, we describe the nature of the Paleolake Hula from the Last Glacial Maximum (LGM) to the start of the Holocene. Until c. 17.2 cal ka BP, Paleolake Hula existed as a relatively large and well-buffered waterbody. A rapid and substantial drawdown of the lake occurred at 17.2 cal ka BP, followed by more frequent changes in the position of the shoreline in a smaller and shallower lake, resulting in the deposition of alternating near-shore and deeper lacustrine facies. Since the LGM, seven beds of structureless, silty sediments preserve archeological artifacts belonging to three Epipaleolithic cultures as well as the Early Neolithic pre-pottery Neolithic A culture. These sediments were deposited during phases of low lake level during which times humans waded into the shallow part of the lake, leaving behind stone and bone tools such as bladelets, lunates and burins, fishing hooks, line weights and net sinkers. Using radiocarbon-dated charcoal and a Bayesian statistical model, we produced a chronostratigraphic model for the archeological site, which enables the comparison of proxy paleoclimate records produced from this site's sediments with regional archives as well as with global trends and changes in the Northern Hemisphere climate. Periods of low lake stands are correlated with the end of the LGM, Heinrich Event 1, and the beginning of the Younger Dryas Stadial. High water stands occurred contemporaneously with the peak of the LGM and during the Bølling–Allerød interstadial. This new water-level record from Lake Hula confirms that lake-level changes here broadly paralleled those of the Dead Sea and Sea of Galilee during the late Pleistocene, highlighting the importance of northern water sources to the overall water balance of the lakes along the Dead Sea Transform. [ABSTRACT FROM AUTHOR]

Archaeologists have long been puzzled by the exact age of Paleolithic cave art in Europe especially in the Franco-Cantabrian region with hundreds of decorated caves because the creation of this parietal art (paintings, drawings and engravings) is closely tied to the appearance of first modern humans in Europe and their ways of life. The Dordogne region, one of the richest regions in terms of Paleolithic cave art in the world with more than 200 cave sites, is currently known to provide figures of cave art solely made with mineral coloring matters that cannot be dated directly. Using in-situ non-invasive Raman spectroscopy combined with portable X-ray fluorescence analysis as well as visible and infrared imaging of the decor of the Font-de-Gaume cave, we show the presence of a large number of charcoal-based Paleolithic figures besides others made of iron and manganese oxides in the main galleries for the first time. The creation periods of the cave art at Font-de-Gaume are mainly attributed to the Magdalenian period and probably more complicated constituted of at least two creation phases than commonly established as shown by the direct or partial superimposition of carbon-based and iron- and/or manganese-based figures. Our new results contribute to a better understanding of the organisation of the ornamentation and thus of the imaginary language of our Prehistoric ancestors. The discovery opens new research possibilities for re-reading of the complex panels and absolute radiocarbon dating. [ABSTRACT FROM AUTHOR]

This study examines the frequency use of cooking fuels by residents of four urban areas in Uganda (Kampala, Lira, Soroti, and M'bale). The specific objective is to identify urban dweller characteristics influencing the frequency of use of fuelwood, charcoal, kerosene, gas, or electricity in daily cooking. An ordered probit regression uses the survey data to estimate five relationships of cooking fuel use frequency generating measures of probability use in response to socio-demographic, income, and location characteristics. Charcoal and firewood remain the key cooking fuels and their use exposes families to excessive levels of toxic emissions. The probability of frequent firewood use increases among elderly, those with children or lower incomes, and residing outside Kampala. Frequency of cooking with charcoal decreases with higher age, having children, or residing in Kampala, but increases if married, with high income, or if college educated. The frequent use of liquid gas or electricity increases with income and among the college educated, but there is no detectable effect of residing in Kampala, likely due to hindered progress of expanding supply infrastructure. Targeting meal preparers with public education campaigns offers a path of changing cooking fuels use to those less polluting. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) is one of the most widely used thermoplastic materials for 3D printing, particularly in the Fused Filament Fabrication technique. However, the printing process generates waste products and even though PLA is compostable, the possibility of recycling it provides ecological and economical benefits. In this work, a study on the stabilization of recycled PLA using charcoal (CC) was carried out, with the aim of overcoming the well-known problem of degradation (reduction in molecular weight) of PLA, during remelting. Microscopic investigations showed good dispersion of the filler in the polymer matrix, as well as better adhesion between the printed layers. Thermal analyses (Differential scanning calorimetry and thermogravimetry) indicate a stabilization of PLA waste because of the addition of small concentrations of CC to the recycled polymer matrix. These data are confirmed by GPC analyses, which show that the addition of filler is associated with higher molecular weight. Mechanical analysis indicated improved elongation at break and elasticity. Finally, a key ring was printed as an example of the better printability of the filament containing CC. The results indicate that a stabilization of the recycled PLA with a very low concentration of CC has been achieved. Improved 3D printability and properties of the 3D printed objects can be attained through recycling and recovery of wasted PLA, according to sustainability and circular economy matters. [ABSTRACT FROM AUTHOR]