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Borassus flabellifer (Palmyra) fruit fiber (PFF) was extracted and converted into biocarbon materials at different carbonization temperatures of 400°C, 600°C, and 800°C under N2 atmosphere for 1 h. The physicochemical properties of obtained biocarbon materials were investigated via CHNS, SEM‐EDX, FTIR, RAMAN, XRD, BET‐specific surface area, and TGA techniques. The obtained results were correlated with the capacitive energy storage application of biocarbon materials. The highest specific surface area of 46.36 m2 g−1 was observed for the biocarbon materials obtained at 800°C, which also showed superior capacitive performances. The specific capacitances of PFF‐derived biocarbon materials obtained at 400°C, 600°C, and 800°C are respectively found to be 28.58, 37.07, and 45.76 F g−1 at 1 A g−1 employing 1M KOH as electrolyte. The biocarbon materials obtained at 800°C showed the highest specific energy and power of 1.99 and 261 W kg−1 at 1 A g−1. [ABSTRACT FROM AUTHOR]

The preparation of biocarbons from cellulose fibres utilised in the production of baby nappy mats (sourced from Feniks Recycling company, Poland) for the removal of methylene blue and rhodamine B dyes has been documented. A Brunauer, Emmett and Teller analysis revealed a surface area within the range of 384 to 450 m2/g. The objective of this study was to investigate the removal efficiency of dyes from aqueous solutions by biocarbons, with a particular focus on the influence of various parameters, including pH, dye concentration, adsorbent dosage, shaking speed, contact time, and temperature. The maximum adsorption capacity of the dyes onto the biocarbons was found to be 85 mg/g for methylene blue and 48 mg/g for rhodamine B, respectively. The Langmuir equation proved to be the most suitable for interpreting the sorption of organic dyes. The adsorption process was found to exhibit a chemisorption mechanism, effectively mirroring the pseudo-second-order kinetics. Furthermore, the adsorption of dyes was observed to be endothermic (the enthalpy change was positive, 9.1–62.6 kJ/mol) and spontaneous under the tested operating conditions. The findings of this study indicate that biocarbons represent a cost-effective option for the removal of methylene blue and rhodamine B. The adsorption method was observed to be an effective and straightforward approach for the removal of these dyes. The results of the Boehm titration analysis and zero charge point value indicated that the synthesised biomaterials exhibited a slightly basic surface character. [ABSTRACT FROM AUTHOR]

The primary goal of the research is to develop a resilient material for electromagnetic interference (EMI) shielding. This study investigates the mechanical, dielectric, and electromagnetic interference (EMI) shielding properties of a composite material reinforced with biocarbon extracted from abaca bract and pineapple fiber in a rigid vinyl ester matrix. The biocarbon is obtained through a pyrolysis process, ensuring its origin from sustainable sources. The fabrication process involves employing the hand layup method, adhering to ASTM standards for comprehensive characterization. Among the fabricated composites, VB3, featuring 2 vol% of biocarbon and 40 vol% of pineapple mat fiber, stands out for exhibiting superior mechanical properties. It achieves a tensile strength of 143 MPa, flexural strength of 184 MPa, compression strength of 161 MPa, and impact energy of 4.31 J. Conversely, VB4, with a higher volume of biocarbon, experiences a slight reduction in mechanical properties attributed to biocarbon agglomeration, while showcasing an enhanced Shore-D hardness of 82. Silane treatment of both pineapple fiber and biocarbon contributes to improved adhesion in the matrix. In terms of electromagnetic interference (EMI) shielding, VB4 surpasses others, delivering maximum shielding effectiveness with total shielding values of 11.18 dB, 30.53 dB, 54.16 dB, and 65.51 dB for frequency bands at 8 GHz, 12 GHz, 16 GHz, and 20 GHz. Similarly, in dielectric properties, VB4 outperforms other designations with a dielectric constant of 9.8, 7.4, 5.8, 4.5, and dielectric loss values of 0.15, 0.31, 0.42, and 0.5 for the respective frequency bands. Moreover, increased biocarbon content further enhances the hydrophobic behavior of the matrix in VB4, achieving a water contact angle of 97°.These findings highlight the multifunctional capabilities of VB4, demonstrating not only superior mechanical strength and EMI shielding but also enhanced dielectric properties and hydrophobic nature. The comprehensive approach to incorporating biocarbon and pineapple fiber, coupled with silane treatment, contributes to the overall performance and versatility of the composite material. [ABSTRACT FROM AUTHOR]

Biochar, a carbon‐rich biomass material has emerged as promising reinforcement and offers versatile applications and potential benefits in various fields, especially in fused deposition modeling (FDM). This study focuses on the development and characterization of groundnut shell‐derived biocarbon (GNSC) reinforced polylactic acid (PLA) filaments for FDM. The GNSC was synthesized through pyrolysis using a tubular furnace at temperatures 700, 800, and 900°C. Synthesized carbon was characterized using Raman spectroscopy, XRD, and SEM analysis. The results showed that the synthesized carbon particles were graphitic, spherical, and nanosized with an average diameter of 40 nm. The preferred biocarbon material, GNSC800 was selected for its high carbon content (98.25%) observed through EDX analysis. Composite filaments were produced with different GNSC800 loadings of 0.25%, 0.5%, and 0.75% using solvent casting and extrusion techniques. Thermal stability was evaluated using TGA and DSC, which showed improved properties with the addition of biocarbon. The mechanical properties and electrical conductivity were enhanced with the inclusion of biocarbon. The data were also validated using ANOVA and Tukey's test. Filament with the 0.5 wt% loading showed the most favorable thermomechanical properties exhibiting a 39.8% increase in tensile strength and a 17.5% improvement in tensile modulus. [ABSTRACT FROM AUTHOR]

There has been a rising interest in the iron and steel industry in replacing fossil-based carbon carriers in their processes because they are the main origin of the anthropogenic carbon emissions within the industry. The use of bio-based carbon carriers could be one solution to partly tackle this challenge. Conventionally, biocarbon is produced by pyrolysis with fixed heating rate, pyrolysis temperature, and retention time. Although the mechanisms behind the formation of biocarbon and the decomposition temperatures of the main compounds of biomass-based materials are known, this knowledge is rarely being utilized in the design of commercial pyrolysis reactors, even though the pyrolysis mechanism-based approach increases the biocarbon yield. In this study, the mechanistic pathway of carbonization of lignocellulosic biomass is taken into account to produce biocarbon with higher yield and quality than conventional pyrolysis with the same process time. Results show that when the process time is the same in both methods, segmented pyrolysis increases biocarbon yield up to 5.4% within a pyrolysis temperature range from 300 °C to 900 °C. Also, fixed carbon yield increased 1.5% in this temperature area. When using segmented pyrolysis, the most suitable pyrolysis temperature is 700 °C based on the characteristics of the produced biocarbon. [ABSTRACT FROM AUTHOR]

An electrochemical sensor was developed using N, P-codoped biocarbon modified glassy carbon electrode for ultrasensitive nitrite detection. The biocarbon was derived from sustainable chitosan biopolymer integrated with phosphorus functionality via triphenylphosphine. Controlled hydrothermal treatment and pyrolysis yielded a hierarchically porous structure with high surface area of 152 m2/g favorable for electrocatalysis. X-ray photoelectron spectroscopy confirmed uniform N, P-doping within the carbon lattice. Using ferro/ferricyanide redox probe, an excellent electron transfer rate constant of 18.7 s− 1 was obtained. Amperometric method displayed two wide linear ranges of 0.1–500 µM and 500–2000 µM nitrite with a remarkably low limit of detection down to 90 nM. This sensor showed negligible interference from common metal ions and relative standard deviation below 5%. Over 95% initial current response was retained following continuous usage for 25 days, highlighting satisfactory stability. Successful practical analysis of various food products further proves the superiority over previous carbon nanomaterial based electrochemical nitrite sensors in terms of tunability, cost-effectiveness and scalability for real sample assays. [ABSTRACT FROM AUTHOR]

The emerging industrial need requires effective energy efficient materials and processing technologies that can be made engineering better. In this present study, a new attempt has been made to improve the effortless joining process of AA7075 T651-AZ31B base materials by using non-consumable rotating tool with novel biolubricant (biocarbon). The biocarbon was thermally reduced (TRB) from wheat straw via low temperature pyrolysis process at 450 °C. The fine biocarbon particles of sizes of about 1–3 µm are then surface modified to prevent the clustering effect using a silane chemical. The sound weld joints were prepared with the help of vertical machining centre as lap joint format. According to the result, the thermal reduction on the biocarbon particle makes the particle lesser impurities. The ordered structure biocarbon effectively offered the lubrication effect and improved the microstructure. The weld made with 1 vol% of biocarbon scored the highest tensile strength of 348 MPa, % of elongation of 28, microhardness of 106 Hv, and Charpy impact toughness of 23.4 J respectively. Similarly, the wear properties show improved wear resistance for large biocarbon particle dispersed weld. The microstructure of welded portion shows highly refined and typically smaller grains. The heat-affected zone (HAZ) and thermo-mechanically treated zone (TMTZ) are typically occupied lesser orbit from the weld pool. The weld bead microstructure reveals improved joining geometry for biocarbon-assisted welds even after more trials. These high strength and joint efficient dissimilar welded joints could be used in automotives, airlines, and shipping where joining of high strength alloys frequently done. [ABSTRACT FROM AUTHOR]

Pedalium murex wastes comprising leaves, flowers, fruits, and seeds were used as precursors to synthesize biocarbon. The Brunauer-Emmett-Teller-specific surface area of 305 m2 g−1 with micro- and mesopores was identified using gas sorption analysis. The three-electrode configuration of a supercapacitor was used to identify the cathodic (−1.2 V) and anodic (0.9 V) limits of the carbon material vs Ag/AgCl(aq.) reference in 1.0 M Na2SO4(aq.). The reversible hydrogen sorption in micropores may be responsible for the extended cathodic potential limit of carbon electrodes. Symmetrical supercapacitors with three commercial-level mass-loaded electrodes were used to evaluate the electrochemical performance. EIS measurements were carried out with three different numbers of frequencies per decade to see their influence on the Warburg diffusion resistance and the relaxation time constant of the supercapacitor. The presence of significant quantities of microspores enables the aqueous supercapacitor with 1.0 M Na2SO4(aq.) to operate with a high cell potential of 1.6 V. The single-electrode-specific capacitances of 112 F g−1, 90 F g−1, and 54 F g−1 at 1.6 V were estimated for the supercapacitors with 10 mg cm−2, 20 mg cm−2, and 30 mg cm−2 areal active material mass loading, respectively, at 0.1 A g−1. Excellent coulombic efficiency of 99% and energy efficiency of 78% were obtained for 10 mg cm−2 mass loading. The specific energy and specific power of 9.7 Wh kg−1 and 2930 W kg−1 were estimated for the fabricated device. The stability of the supercapacitor was analyzed by conducting uninterrupted GCPL cycling up to 50,000 cycles. [ABSTRACT FROM AUTHOR]

The results of obtaining titanium carbide by a vacuum-free electric arc method using various types of biocarbon obtained by classical pyrolysis of biomass waste, such as tangerine peel, pomelo peel, banana peel, pine nut shells, and walnut shells, are presented. An analysis of X-ray diffraction patterns of the synthesized materials showed the repeatability of the experiment with the receipt of diffraction maximums indicating the formation of a cubic structure of titanium carbide. An analysis of the thermal oxidation of the resulting powders showed that the process proceeded slowly up to 1000°C, but the rate of oxidation increased significantly with temperature. It has been established that the weight of the studied titanium carbide powders obtained using various types of carbon increased upon thermal heating in an oxidizing atmosphere, as confirmed by thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Biocarbon catalysts for reverse water‐gas shift reaction (RWGS) were produced from pyrolyzed fern and willow impregnated with iron and nickel nitrates. This reaction can partake during Fischer‐Tropsch synthesis (FTS) by consuming CO2 and lowering both the H2/CO ratio and the efficiency in the production of fuels. RWGS has attracted much attention to widespread utilization of CO2 through the production of syngas. The catalysts were therefore tested in a fixed‐bed reactor at 400 °C as it is the maximal temperature for FTS and high RWGS. They showed high selectivity towards CO (>84 %) and fair conversion (<17 %) compared to rust (81 %, 30 %, respectively) and Fe‐impregnated alumina (100 %, 8 %). No loss in selectivity and conversion was observed for a longer residence time (288 h). Biomass inherent metals could provide reactive gas adsorption sites that improve conversion by dispersing electrons which reduces adsorption and dissociation energy barriers. K, Mg and Ca in fern biocarbon catalysts may be related to the higher CO2 uptake compared to willow catalysts. Electron deficient sites produced by reduction of biocarbon oxygen functional groups may facilitate CO2 uptake and activation. Ni‐impregnated fern‐based biocarbon showed the highest activity, due to the synergetic effect of the inherent metals, O vacancies and strong metal‐carbon interactions. [ABSTRACT FROM AUTHOR]

This article describes the production of bioadsorbents coming from seven different kinds of organic waste, produced in huge quantities in households, in a two-stage process. In order to determine the influence of the process parameters of carbonization (I stage) and activation with potassium hydroxide solution (II stage), the following analysis of the physicochemical properties of each sample at each stage processing was performed: base elemental composition, structure properties, surface morphology, thermal stability, crystallinity, and transmittance spectra characteristic bands. There was a lack of research on samples after each stage of waste processing in the literature. Addressing this allowed us to evaluate the transformative potential of each kind of organic waste included in the research and select the best waste for the production of bioadsorbents commonly used in environmental protection. Moreover, the results were compared with the ones in the literature. The utilization of particular kinds of organic waste seems to be especially important taking into account the strategy of waste management and sustainable development. [ABSTRACT FROM AUTHOR]

This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae‐based method are not hazardous, they are eco‐friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs‐CSKPH) did not appear in the XRD diffractograms, but the SEM‐EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps‐CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs‐CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2. [ABSTRACT FROM AUTHOR]

This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae‐based method are not hazardous, they are eco‐friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs‐CSKPH) did not appear in the XRD diffractograms, but the SEM‐EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps‐CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs‐CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2. [ABSTRACT FROM AUTHOR]

In this work, mixed bio-oil (MBO) is transformed into valuable biocarbon through slow pyrolysis technique. MBO was accomplished in a semi-batch reactor at 600 and 900 °C temperature, 10 °C min−1 heating rate, and 30 min holding time under a non-oxidizing environment. The produced mixed bio-oil-derived biocarbon (MBOB) was characterized by its surface properties, thermal stability, elemental composition, thermal conductivity, BET surface area, surface morphology, and electrical conductivity. The pyrolysis outcomes established that the temperature has a predominant impact on the variation in yield and properties of MBOB. Characterization results of MBOB exposed increased properties (thermal stability, electrical and thermal conductivity, graphitic content, carbon content, and HHV) at 900 compared to 600 °C. Also, the elemental and EDS investigation of MBOB established a broad diminution in O2 and H2 at 900 than 600 °C. The purest form of carbon with enhanced thermal stability, higher carbon content, smoothness, and bigger particles of biocarbon (verified by SEM) is accomplished at 900 °C. The electrical and thermal conductivity (EC and TC) of MBOB increased with increasing the temperature from 600 to 900 °C due to the close contact of biocarbon particles. Finally, an investigation of the particle size of MBOB established that the majority of particles are within 1.5 to 1.7 µm. [ABSTRACT FROM AUTHOR]

Mining sector has been the central attention of the business and public policy sustainable development scheme for several years. Reclamation territories are with potential carbon sequestration capacity in degraded mining areas and can be an impeccable option for achieving sustainable development goal-13. This paper made an investigation about the presence of heavy metals in reclaimed area possibilities to improve reclaimed soils with biochar with idea to enhance ecosystem carbon pool and atmospheric CO2 sequestration capacity to offset CO2 emission and soil organic carbon losses. The results show that the carbon content in biochar is 46.6 % and would be classified in class 2 according to the International Biochar Initiative. H/C and O/C atomic ratios could be useful for restoration of degraded poor mine soils through enhanced carbon sequestration. O/C ratio is 0.085 mol mol–1 and half-life of biochar is 2795.65 years, which confirm the biochar stability. For each kilogram of biochar incorporated into the soil, 144 g of carbon were sequestrated 52,8 % CO2 emission reduction. Hence, the biochar developed in this study can be used in carbon-deficient soils with the added benefit of long-term carbon storage. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the effects of biochar and Trichoderma spp. on soil chemical and biological properties and to determine whether their combined application could be a sustainable alternative in soil cultivated with tomatoes. We hypothesized that the application of biochar and Trichoderma spp. would alter the soil's chemical and biological properties. Methods: To test this hypothesis, we conducted a field experiment and evaluated the soil's chemical and biological properties. Results: Our findings revealed that seven soil parameters, namely pH, P, Na+, K+, Ca2+, Mg2+, and total organic C, had a significant influence on the activity of acid phosphatase and urease. We further used machine learning models of soil properties to predict the efficiency of biochar and Trichoderma spp. in improving soil quality. These models demonstrated satisfactory performance in simulating the changes in soil properties induced by biochar, based on both predicted and experimental yield results. Conclusion: Overall, our study provides important insights into the potential use of biochar and Trichoderma spp. as sustainable alternatives to mineral fertilizer for increasing tomato yield, while also highlighting their effects on soil biological and chemical properties [ABSTRACT FROM AUTHOR]

The aim of this research was to create a cleaner production polymer filament using waste banana bracts biocarbon (BBB) for 3D-printing applications. In this work, ABS is used as a polymeric material together with BBB at concentrations of 3.0, 6.0, and 9.0 wt. %, respectively. In order to examine the impact of infill ratio on the properties of ABS–BBB composite filament, the printing is done with two distinct infill ratios such as 25% and 75%. Mechanical, fatigue and wear characteristics as well as the water contact angle have been examined to ascertain the effectiveness of biocarbon addition. The findings showed that the inclusion of 3.0 wt. % BBB with 75% of infill ratio provides the tensile strength of 33.6 MPa, tensile modulus of 1.93 GPa, flexural strength of 58.7, flexural modulus of 2.96 GPa, yield stress of 28.5 MPa and Izod impact of 5.2 J. In addition, the maximum fatigue life counts for material designation N11 are measured to be 2495, 1753, and 1485 for 25%, 50%, and 75% of UTS, respectively, when 3.0 wt. % of biocarbon is added to ABS with a 75% infill ratio. However, the material designation N2 having 25% of infill ratio and 6.0 wt. % of BBB has the lowest COF and wear loss of 0.26 and 0.018 g. A contact angle test reveals that a material is hydrophobic up to 6.0 wt. % BBB addition. These polymer 3D-printing material could be used in the construction sector with high environmental concern. [ABSTRACT FROM AUTHOR]

The use of processed biomass, derived from agricultural crop residues, as a fuel is becoming increasingly important in the energy sector, which additionally allows for the management of excess waste that is a burden on the environment. The aim of this study was to investigate the effect of the torrefaction process conditions in a carbon dioxide atmosphere on the chemical structure of biocarbon and the energy parameters of the produced product, which can be a solid biofuel. The biomass chosen for the experimental work was flax shive. Determinations of the heat of combustion of the produced biocarbon samples were carried out using a KL-10 calorimeter, and identification of the molecular structure of the product and the starting biomass was carried out using infrared spectrometry. It was confirmed that increasing the temperature of biomass torrefaction increases the heat of combustion of the product, with this parameter obtaining the most favourable value for biocarbon obtained during torrefaction at 320°C and for 20 to 30 minutes. The heat of combustion of the biocarbon produced during torrefaction at 320°C and for 30 minutes was 25.92 MJ/kg, with a feedstock mass loss of 41%. Such conditions lead to a significant conversion of the chemical structure of the biomass, with no complete destruction of organic structures.

La combinación de fertilización química y biocarbón en la agricultura es esencial, la fertilización química aporta nutrientes inmediatos, mientras que el biocarbón, como enmienda al suelo, mejora la retención de nutrientes y la salud de las plantas. Los resultados pueden impulsar la eficiencia agrícola y la sostenibilidad, beneficiando a los agricultores como a la producción de maíz a nivel mundial. La investigación se desarrolló con el propósito de evaluar el efecto combinado de fertilización química y biocarbón en crecimiento y desarrollo del cultivo de maíz, para lo cual se utilizó un diseño cuadrado latino simple. Los tratamientos fueron: testigo absoluto, 10 t/ha biocarbón, 20 t/ha biocarbón, 10 t/ha biocarbón + 4,375 t/ha urea, 20 t/ha biocarbón + 4,375 urea donde se manipularon los fertilizantes, se utilizó la prueba estadística Duncan con nivel de significancia (p

Seaweed biomass of Gracilaria edulis was effectively converted into biocarbon materials at 800°C for 1 hour under nitrogen gas flow atmosphere. The effect of HCl acid washing and ZnCl2‐assisted chemical activation process on the physicochemical and capacitive performances was investigated and the obtained results were compared with their pristine counterpart. The formation of N, O, and S self‐doped biocarbon materials from G. edulis biomass was confirmed by carbon, hydrogen, nitrogen, and sulfur (CHNS), scanning electron microscopy‐energy dispersive X‐ray (SEM‐EDX) and X‐ray photoelectron spectroscopic (XPS) analyses. Further, the specific surface area of acid‐washed and activated biocarbon materials were respectively found to be 1100 and 774 m2 g−1, which are much greater than their pristine counterpart (111 m2 g−1). The obtained pristine (GE‐PC), acid‐washed (GE‐AWC), and activated (GE‐AC) biocarbon materials were effectively explored as the electrode material for symmetric supercapacitor and showed the specific capacitance value of 33.9 (GE‐PC), 58.3 (GE‐AWC) and 76.5 (GE‐AC) F g−1 at 1 A g−1 using 1 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

An integrated biorefinery concept is a novel and economical process intensification methodology for efficient utilization of biomass components. In this research, microalgae (Scenedesmus sp.) slurry with biomass concentration of 8.5 wt.% was parallelly fractionated using two techniques: 'flash hydrolysis (FH)' and 'acid hydrolysis (AH)'. FH was performed at 240 °C with a residence time of 10 ± 2 s in a continuous flow reactor, whereas AH was performed at 155 °C and reaction time of 15 min in a batch reactor. About 63% of microalgal biomass was solubilized in liquid hydrolysate through both FH and AH. However, AH had an advantage over FH in recovering microalgae proteins and carbohydrates. FAME recovery through solvent extraction from FH and AH derived wet solids (insoluble microalgae) was 40 and 63%, respectively. Finally, the FH- and AH-derived post extraction solid residue was thermally activated using K2CO3 to produce highly microporous biocarbon nanosheets with BET surface areas of 712 and 1289 m2·g−1, respectively. Overall, an integrated process was developed using two potential hydrolysis techniques to maximize utilization of microalgae components. [ABSTRACT FROM AUTHOR]

Management of catering waste, including coffee grounds, is becoming an important economic issue. Coffee grounds contain both organic compounds and mineral compounds, including macronutrients and micronutrients. The purpose of the study was to determine the fertilizer value of composts obtained using coffee grounds. The compost was prepared from vegetable raw material and coffee grounds with the addition of biocarbon or effluent obtained during yeast production. The experiment included 4 treatments: M – control - maize straw; M+CG – maize straw + coffee grounds; M+CG+BC – maize straw + coffee grounds + willow biochar; M+CG+E – maize straw + coffee grounds + yeast effluent. The amount of waste materials introduced into the composted maize biomass was limited not only due to their physical parameters, but also because of the humidity of the feedstock. The ratios of feedstocks used in individual treatments by weight of the dry matter were: M+CG – 1:0.89; M+CG+BC – 1:0.89:0.1; M+CG+E – 1:0.89:0.07. After mixing the materials, moisture of the mixture was equilibrated to 60% by weight. Aeration of the biomass was performed in cycles, 6 times a day; the air was flowing through the bioreactor in the amount of 15 dm³ min-1 for 60 min; the biomass was manually shifted every 10 days. The content of macronutrients and trace elements was determined in the product with regard to the admissible values for organic fertilizers. Composts with a very high proportion of coffee grounds meet the criteria regarding the minimum NPK and organic matter content in the fertilizer aspect. Coffee grounds are characterized by a low content of heavy metals, which in practice can cause their dilution in biological processing products. Utilization of the effluent from a yeast factory for irrigation of composted biomass is not possible on an industrial scale. A small addition of this waste leads to significant salinity of the compost. [ABSTRACT FROM AUTHOR]

The structural and physio-chemical properties of biochar are crucial to determining biochar's quality and the adequate application. Specifically, the large porosity of biochar has been known as a favorable feature, especially for environmental remediation. In this regard, physical and chemical modifications have been used to improve biochar's porosity which requires high-energy consumption and involves chemical agents. The objective of this study was to prepare biochar with developed porosity using mild treatments. Arundo donax and olive stone were demineralized by a water-washing method. Treated and non-treated biomasses were pyrolyzed, and part of the derived samples was subjected to wet ball milling. Samples were characterized with proximate, Fourier transform infrared, particle size, and physisorption analyses. The effect of demineralization depended on the biomass type, as ash reduction only influenced Arundo donax-derived biochar, which was attributed to the difference in initial ash content that was relatively low for olive stone. The carbonization yield decreased by 46% for the Arundo donax biomass after demineralization. Moreover, demineralization expanded the surface area and total pore volume of the Arundo donax biochar. The ball milling was effective in producing micro-sized biochar particles with a mean size ranging between 30 ± 2 µm and 42 ± 2 µm and between 13 ± 1 µm and 22 ± 2 µm for Arundo donax and olive stone without and with demineralization, respectively. Ball milling increased the surface area of non-demineralized Arundo donax by 47% and demineralized Arundo donax by 124%. Additionally, ball milling increased the surface area of non-demineralized olive stone by 65% and demineralized olive stone by 62%. [ABSTRACT FROM AUTHOR]

In this work, an eco-saving and green anode structure (CRC) of MnO/Mn 3 O 4 nanoparticles (NPs) anchored on biocarbon substrates derived from cassava residues (CRs) was designed and fabricated successfully by an in-situ method from MnCl 2 and CRs. The amount of MnO/Mn 3 O 4 NPs in the CRC can be effectively modulated by altering the mass ratio of MnCl 2 to CRs. In Li-ion batteries, CRC anodes exhibit outstanding electrochemical performances such as high Coulombic efficiency, high capacity, excellent rate capacity, and stable cycling. The high reversible capacity of 698 mAh g−1 at 100 mA g−1 can be achieved even after 100 cycles. This could be accredited to the special structure of MnO/Mn 3 O 4 NPs and biocarbon substrates. First, CR-derived biocarbon favors the alleviation of volume change and prevents the aggregation of MnO/Mn 3 O 4 NPs during cycling. Then, an appropriate amount of MnO/Mn 3 O 4 NPs formed on the surface and empty cages of biocarbon generate various free contacting channels between the electrolyte and active materials. Finally, MnO/Mn 3 O 4 NPs intensify the electrochemical activity of biocarbon, leading to an increase in Li-storage capacities. Therefore, the facile in-situ method in this work is quite promising to produce cost-effective and eco-friendly anodes for Li-ion batteries utilizing recycled CRs and simple chemicals. [Display omitted] • MnO/Mn 3 O 4 nanoparticles anchored on biocarbon substrates (CRCs) are prepared by a simple process. • CRCs possess large specific surface areas and porous structures. • CRC anode with ratio of MnCl 2 /cassava residues of 3 exhibits outstanding electrochemical properties. • CRC_3 anode delivers a capacity of 698 mAh g−1 after 100 cycles. • The excellent electrochemical efficiency results from the special properties of CRCs. [ABSTRACT FROM AUTHOR]

The present work reports the green synthesis and hydrogen storage capacities of porous biocarbon (CK-700) and, N/S doped biocarbon (ACK-1) prepared by green and sustainable carbonization methods from pistachio shells. The hydrogen uptake capacity of CK-700 and ACK-1 were investigated at −196 °C and in the pressure range of 5–50 bar. A green and sustainable route is described for the synthesis of N/S doped biocarbon (ACK-1) by using a combined hydrothermal carbonization and chemical activation process in which Na2S2O3 applied as an activating agent. The characterization of N/S doped biocarbon and raw biocarbon were investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analyses. The hydrogen storage capacities of the green synthesized CK-700 and ACK-1 were measured by IGA dynamic gas adsorption analyzer. The hydrogen adsorption capacity of CK-700 and ACK-1 were measured and, the highest hydrogen adsorption capacity of ACK-1 was obtained to be 4.55 wt% under pressure of 50 and at 73 K, while the lowest hydrogen uptake capacity of CK-700 was obtained to be 2.24 wt% under pressure of 5 bar and at 73 K in raw biocarbon. Hydrogen storage capacity of the green synthesized porous biocarbon and N/S doped porous biocarbon were studied. Biocarbon nanoparticles were prepared via green and sustainable method. The addition of sodium thiosulfate as a nontoxic agents plays a synergetic catalytic role. Increase of pore sizes around 765 m2/g in porous N/S doped biocarbon essential for the enhanced hydrogen adsorption. [ABSTRACT FROM AUTHOR]

The use of processed biomass, derived from agricultural crop residues, as a fuel is becoming increasingly important in the energy sector, which additionally allows for the management of excess waste that is a burden on the environment. The aim of this study was to investigate the effect of the torrefaction process conditions in a carbon dioxide atmosphere on the chemical structure of biocarbon and the energy parameters of the produced product, which can be a solid biofuel. The biomass chosen for the experimental work was flax shive. Determinations of the heat of combustion of the produced biocarbon samples were carried out using a KL-10 calorimeter, and identification of the molecular structure of the product and the starting biomass was carried out using infrared spectrometry. It was confirmed that increasing the temperature of biomass torrefaction increases the heat of combustion of the product, with this parameter obtaining the most favourable value for biocarbon obtained during torrefaction at 320°C and for 20 to 30 minutes. The heat of combustion of the biocarbon produced during torrefaction at 320°C and for 30 minutes was 25.92 MJ/kg, with a feedstock mass loss of 41%. Such conditions lead to a significant conversion of the chemical structure of the biomass, with no complete destruction of organic structures. [ABSTRACT FROM AUTHOR]

To meet the ever‐increasing demand for solar energy conversion, the exploration of new materials that improve energy and cost efficiency is great significance. Particularly in dye‐sensitized solar cells, extensive efforts have been made to substitute the traditional metal‐based components with various carbon materials. As the result, carbon materials such as carbon dots, carbon nanotubes, grapheme, and porous carbon materials are explored for their components, which are traditionally derived from fossil resources. Recently these carbon materials are widely synthesized or derived from renewable biomasses and getting important in solar energy conversion due to their similar structural, physicochemical, morphological, and functional features of above stated traditional carbon materials. The utilization of these biocarbon materials offers numerous environmental and economic benefits over traditional carbon materials and creates a new pathway towards a sustainable future. Thus, this review summarizes the recent exploration of biocarbon materials in dye‐sensitized solar cells and discusses their emerging opportunities. [ABSTRACT FROM AUTHOR]

Direct methanol fuel cells (DMFC), as a clean and renewable energy device, can alleviate the problems of energy shortage and environmental pollution. Low-cost and high-performance exploitation of bifunctional catalyst materials is beneficial for promoting the large-scale application of DMFC. Here we have fabricated a biomass-derived nitrogen and phosphorus co-doped porous carbon (CSAN10P-2) prepared by a simple and green approach. The carbon material obtained by pyrolysis of hydrogel precursors formed by sodium alginate, silk and polyaniline showed a high specific surface area of 823.4 m2/g and a nitrogen content of 7.28%. The resulting CSAN10P-2 material exhibits high electro-catalytic activity for oxygen reduction reaction (ORR) in alkaline solution with E0 (1.10 V) and E1/2 (0.83 V). In addition, it can be used as a good substrate material for platinum particles (NPs). The Pt/CSAN10P-2 catalysts prepared by loading Pt metal showed excellent catalytic performance and high stability in acidic media and also outperformed Pt/C catalysts in all aspects. This procedure introduces a novel concept for making electro-catalysts of fuel cell. [ABSTRACT FROM AUTHOR]

Formaldehyde is a common indoor air pollutant with hazardous effects on human health. This study investigated the efficiency of biocarbon (BC) functionalized with variable contents of MnO2 for formaldehyde removal in ambient conditions via integrated adsorption-photocatalytic degradation technology. The sample with the highest formaldehyde removal potential was used to prepare a functional coating made of acrylic binder mixed with 20 wt% of the particles and applied on beech (Fagus sylvatica L) substrate. SEM images showed that MnO2 was deposited around and inside the pores of the BC. EDX spectra indicated the presence of Mn peaks and increased content of oxygen in the doped BC compared to pure BC, which indicated the successful formation of MnO2. Raman spectra revealed that the disorder in the BC's structure increased with increasing MnO2 loadings. FTIR spectra of BC–MnO2 samples displayed additional peaks compared to the BC spectrum, which were attributed to MnO vibrations. Moreover, the deposition of increased MnO2 loadings decreased the porosity of the BC due to pores blockage. The BC sample containing 8 % Mn exhibited the highest formaldehyde removal efficiency in 8 h, which was 91 %. A synergetic effect between BC and MnO2 was observed. The formaldehyde removal efficiency and capacity of the coating reached 43 % and 6.1 mg/m2, respectively, suggesting that the developed coating can be potentially used to improve air quality in the built environment.

Abstract This study presents a green method of producing copper nanoparticles (CuNPs) using aqueous extracts from Sargassum spp. as reducing, stabilizing, and capping agents. The CuNPs created using this algae‐based method are not hazardous, they are eco‐friendly, and less toxic than their chemically synthesized counterparts. The XRD characterization of the CuNPs revealed the presence of Cu and CuO, with a crystallite size ranging from 13 to 17 nm. Following this, the CuNPs were supported onto a carbon substrate, also derived from Sargassum spp. (biochar CSKPH). The CuNPs in biochar (CuNPs‐CSKPH) did not appear in the XRD diffractograms, but the SEM‐EDS results showed that they accounted for 36 % of the copper weight. The voltamperometric study of CuNps‐CSKPH in acid media validated the presence of Cu and the amount was determined to be 2.58 μg. The catalytic activity of CuNPs‐CSKPH was analyzed for the electrochemical reduction of CO2. The use of Sargassum spp. has great potential to tackle two environmental problems simultaneously, by using it as raw material for the synthesis of activated biochar as support, as well as the synthesis of CuNPs, and secondly, by using it as a sustainable material for the electrochemical conversion of CO2.

In this study, we investigated the impact on surface topography and micro-mechanical properties of polyvinyl alcohol (PVA) thin films when loaded with hardwood-derived biocarbon particles (BCP). The PVA/BCP composites were prepared with the conventional film casting method, after varying BCP concentrations of 6, 8, 10, 12, and 20 wt% were added to the PVA solution. Atomic force microscopy (AFM) investigations and nanoindentation tests were performed. The average roughness of the thin films increased with the increase in BCP content. The alternation between dark and light patterns observed in the AFM images showed an irregular surface topography with alternating high peaks and deep valleys. The skewness and kurtosis parameters showed that the different dispersion degrees of the BCP within the PVA matrix influenced the composites' surface roughness. The micro-mechanical properties of the thin film composites depended on the BCP type and concentration. Films reinforced with red oak-derived BCP had higher hardness and Young's modulus compared to films reinforced with willow SV1 and yellow-poplar BCP, which was attributed to the high carbon content and low ash content of red oak BCP. We argue that these results may be extrapolated to other types of BCP-reinforced thin films and can significantly contribute to enabling more efficient methods and protocols for reinforcing polymers with hardwood biocarbon.

The preparation of biocarbons from cellulose fibres utilised in the production of baby nappy mats (sourced from Feniks Recycling company, Poland) for the removal of methylene blue and rhodamine B dyes has been documented. A Brunauer, Emmett and Teller analysis revealed a surface area within the range of 384 to 450 m2/g. The objective of this study was to investigate the removal efficiency of dyes from aqueous solutions by biocarbons, with a particular focus on the influence of various parameters, including pH, dye concentration, adsorbent dosage, shaking speed, contact time, and temperature. The maximum adsorption capacity of the dyes onto the biocarbons was found to be 85 mg/g for methylene blue and 48 mg/g for rhodamine B, respectively. The Langmuir equation proved to be the most suitable for interpreting the sorption of organic dyes. The adsorption process was found to exhibit a chemisorption mechanism, effectively mirroring the pseudo-second-order kinetics. Furthermore, the adsorption of dyes was observed to be endothermic (the enthalpy change was positive, 9.1–62.6 kJ/mol) and spontaneous under the tested operating conditions. The findings of this study indicate that biocarbons represent a cost-effective option for the removal of methylene blue and rhodamine B. The adsorption method was observed to be an effective and straightforward approach for the removal of these dyes. The results of the Boehm titration analysis and zero charge point value indicated that the synthesised biomaterials exhibited a slightly basic surface character.

There has been a rising interest in the iron and steel industry in replacing fossil-based carbon carriers in their processes because they are the main origin of the anthropogenic carbon emissions within the industry. The use of bio-based carbon carriers could be one solution to partly tackle this challenge. Conventionally, biocarbon is produced by pyrolysis with fixed heating rate, pyrolysis temperature, and retention time. Although the mechanisms behind the formation of biocarbon and the decomposition temperatures of the main compounds of biomass-based materials are known, this knowledge is rarely being utilized in the design of commercial pyrolysis reactors, even though the pyrolysis mechanism-based approach increases the biocarbon yield. In this study, the mechanistic pathway of carbonization of lignocellulosic biomass is taken into account to produce biocarbon with higher yield and quality than conventional pyrolysis with the same process time. Results show that when the process time is the same in both methods, segmented pyrolysis increases biocarbon yield up to 5.4% within a pyrolysis temperature range from 300 °C to 900 °C. Also, fixed carbon yield increased 1.5% in this temperature area. When using segmented pyrolysis, the most suitable pyrolysis temperature is 700 °C based on the characteristics of the produced biocarbon.

Los derrames de petróleo son un problema ambiental importante en todo el mundo, derivados de la exploración, extracción, transporte o sabotaje de la infraestructura petrolera. Los avances científicos han llevado al desarrollo de diversas técnicas de remediación, incluida la fitorremediación y la aplicación de biocarbón. Este estudio involucró la recolección de muestras de suelo no contaminadas de las afueras del municipio de El Rodeo (México), la introducción de petróleo crudo y el tratamiento con la siembra de calabaza (Cucurbita pepo) o la aplicación de biocarbón. Luego de cuatro meses de tratamiento, se analizaron las características del suelo, incluyendo pH (7.50; 5.10), conductividad eléctrica (1.50 dSm-1; 0.20 dSm-1) y contenido de minerales: hierro (0.39 ppm; 0.59 ppm), nitrógeno (1.70 ppm; 1343 ppm), fósforo (0.35 ppm; 297 ppm), potasio (1.70 ppm; 1944 ppm), zinc (0.00 ppm; 23 ppm), calcio (0.00 ppm; 0.00 ppm) y plomo (36 ppm; 10 ppm). Si bien las técnicas utilizadas en el estudio no produjeron suelo fértil, redujeron efectivamente los niveles de hidrocarburos totales de petróleo (TPH) y permiten ser implementadas a escala industrial para reducir las concentraciones de hidrocarburos, mitigando así la toxicidad del ecosistema y mejorando el valor estético de las áreas afectadas. Estas medidas brindan beneficios económicos a las comunidades locales al apoyar el turismo y al mismo tiempo reducir la contaminación del agua y el suelo, así como los riesgos para la salud asociados con la exposición a los hidrocarburos.

Mishandling of waste plastics and biomasses is a major global concern. Every year, around 380 million tonnes of plastic are produced, with only 9% being recycled, leading to widespread pollution. Similarly, waste biomass generation from agricultural and forestry sectors accounts for 140 billion metric tonnes, in addition to 2.01 billion tonnes from municipal solid waste. This review paper addresses the gap regarding the integration of 3D printing, upcycling of recycled plastics, and the utilization of waste biomass in sustainable composites. 3D printed parts from recycled plastic have shown comparable mechanical properties compared to virgin materials, which have been further improved by the addition of waste biomass-derived fillers. The paper acknowledges that different printing parameters have substantial influence on the strength, ductility, crystallinity, and dimensional accuracy of printed parts. Therefore, optimizing these parameters becomes crucial for achieving improved mechanical performance. Moreover, incorporating reinforcing agents, stabilizers, chain extenders, compatibilizers, and surface modifiers in plastic recycling and 3D printing presents an excellent opportunity to enhance mechanical properties, thermal stability, adhesion, and dimensional stability. Additionally, the review identifies research gaps and proposes the integration of machine learning and artificial intelligence for enhanced process control and material development, further expanding the possibilities in this field.

A sustainable cow hair‐based biocarbon/sulfur composite was prepared via a melt‐diffusion process and used as cathode for lithium–sulfur (Li−S) batteries, exhibiting high capacity, good rate capability, and excellent cyclability. The effect of the activation process during the formation of the biocarbon was deeply analyzed by thermogravimetry, N2 adsorption, X‐ray photoelectron spectroscopy, scanning and transmission electron microcopy, among others. A correlation between the composition and the surface area with the electrochemical performance was found. The best results were obtained using an activated sample and composite electrode containing 73 wt % sulfur, which present an initial discharge capacity of around 1200 mAh/g and 799 mAh/g after 100 cycles at a current density of 0.1 A/g. Moreover, a specific capacity of ~701 mAh/g was measured at 1 C. The great electrochemical performance of this electrode in Li−S batteries is attributed to the porous carbon structure. Taking into account that hair is one of the major waste produced in the leather sector, this work presents a promising approach to reuse this material by giving it added value through the preparation of carbon/sulfur composites for high‐performance Li−S batteries. [ABSTRACT FROM AUTHOR]

The exploration of biocarbon using various bio-resources has received great importance as the awareness of environmentally benign energy storage technologies is increasing drastically. Additionally, the active mass loading of the electrode in the supercapacitors has recently gained great importance as it meets the industrial requirement as well as provides practical electrochemical performance. In this study, we synthesized activated biocarbon using Datura stramonium seeds through pyrolysis with chemical activation. To achieve real-world performance, biocarbon mass loadings at commercial levels (≥ 10 mg cm−2) were used in the fabrication of symmetrical supercapacitors. The single electrode-specific capacitance of 114 F g−1 was estimated at 1.2 V with excellent coulombic efficiency of 99% and energy efficiency of 82%. We obtained the maximum specific energy of 5.6 Wh kg−1 at 0.1 A g−1 and specific power of 980 Wkg−1. Excellent specific capacitance retention of 100% is noted at the end of 10,000 GCPL cycles at 1.0 A g−1, indicating that symmetrical supercapacitors with synthesized biocarbon possess high stability. [ABSTRACT FROM AUTHOR]