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Abstract Background The holistic characterization of different microbiomes in anaerobic digestion (AD) systems can contribute to a better understanding of these systems and provide starting points for bioengineering. The present study investigates the microbiome of 80 European full-scale AD systems. Operational, chemical and taxonomic data were thoroughly collected, analysed and correlated to identify the main drivers of AD processes. Results The present study describes chemical and operational parameters for a broad spectrum of different AD systems. With this data, Spearman correlation and differential abundance analyses were applied to narrow down the role of the individual microorganisms detected. The authors succeeded in further limiting the number of microorganisms in the core microbiome for a broad range of AD systems. Based on 16S rRNA gene amplicon sequencing, MBA03, Proteiniphilum, a member of the family Dethiobacteraceae, the genus Caldicoprobacter and the methanogen Methanosarcina were the most prevalent and abundant organisms identified in all digesters analysed. High ratios for Methanoculleus are often described for agricultural co-digesters. Therefore, it is remarkable that Methanosarcina was surprisingly high in several digesters reaching ratios up to 47.2%. The various statistical analyses revealed that the microorganisms grouped according to different patterns. A purely taxonomic correlation enabled a distinction between an acetoclastic cluster and a hydrogenotrophic one. However, in the multivariate analysis with chemical parameters, the main clusters corresponded to hydrolytic and acidogenic microorganisms, with SAOB bacteria being particularly important in the second group. Including operational parameters resulted in digester-type specific grouping of microbes. Those with separate acidification stood out among the many reactor types due to their unexpected behaviour. Despite maximizing the organic loading rate in the hydrolytic pretreatments, these stages turned into extremely robust methane production units. Conclusions From 80 different AD systems, one of the most holistic data sets is provided. A very distinct formation of microbial clusters was discovered, depending on whether taxonomic, chemical or operational parameters were combined. The microorganisms in the individual clusters were strongly dependent on the respective reference parameters. Graphical Abstract

Abstract Lignocellulosic biomass is currently underutilized, but it offers promise as a resource for the generation of commercial end-products, such as biofuels, detergents, and other oleochemicals. Rhodococcus opacus PD630 is an oleaginous, Gram-positive bacterium with an exceptional ability to utilize recalcitrant aromatic lignin breakdown products to produce lipid molecules such as triacylglycerols (TAGs), which are an important biofuel precursor. Lipid carbon storage molecules accumulate only under growth-limiting low nitrogen conditions, representing a significant challenge toward using bacterial biorefineries for fuel precursor production. In this work, we screened overexpression of 27 native transcriptional regulators for their abilities to improve lipid accumulation under nitrogen-rich conditions, resulting in three strains that accumulate increased lipids, unconstrained by nitrogen availability when grown in phenol or glucose. Transcriptomic analyses revealed that the best strain (#13) enhanced FA production via activation of the β-ketoadipate pathway. Gene deletion experiments confirm that lipid accumulation in nitrogen-replete conditions requires reprogramming of phenylalanine metabolism. By generating mutants decoupling carbon storage from low nitrogen environments, we move closer toward optimizing R. opacus for efficient bioproduction on lignocellulosic biomass.

Abstract Hybrid thermochemical–biological processes have the potential to enhance the carbon and energy recovery from organic waste. This work aimed to assess the carbon and energy recovery potential of multifunctional processes to simultaneously sequestrate syngas and detoxify pyrolysis aqueous condensate (PAC) for short-chain carboxylates production. To evaluate relevant process parameters for mixed culture co-fermentation of syngas and PAC, two identical reactors were run under mesophilic (37 °C) and thermophilic (55 °C) conditions at increasing PAC loading rates. Both the mesophilic and the thermophilic process recovered at least 50% of the energy in syngas and PAC into short-chain carboxylates. During the mesophilic syngas and PAC co-fermentation, methanogenesis was completely inhibited while acetate, ethanol and butyrate were the primary metabolites. Over 90% of the amplicon sequencing variants based on 16S rRNA were assigned to Clostridium sensu stricto 12. During the thermophilic process, on the other hand, Symbiobacteriales, Syntrophaceticus, Thermoanaerobacterium, Methanothermobacter and Methanosarcina likely played crucial roles in aromatics degradation and methanogenesis, respectively, while Moorella thermoacetica and Methanothermobacter marburgensis were the predominant carboxydotrophs in the thermophilic process. High biomass concentrations were necessary to maintain stable process operations at high PAC loads. In a second-stage reactor, Aspergillus oryzae converted acetate, propionate and butyrate from the first stage into L-malate, confirming the successful detoxification of PAC below inhibitory levels. The highest L-malate yield was 0.26 ± 2.2 molL-malate/molcarboxylates recorded for effluent from the mesophilic process at a PAC load of 4% v/v. The results highlight the potential of multifunctional reactors where anaerobic mixed cultures perform simultaneously diverse process roles, such as carbon fixation, wastewater detoxification and carboxylates intermediate production. The recovered energy in the form of intermediate carboxylates allows for their use as substrates in subsequent fermentative stages.

Abstract Background 5-Aminolevulinic acid (ALA) recently received much attention due to its potential application in many fields such as medicine, nutrition and agriculture. Metabolic engineering is an efficient strategy to improve microbial production of 5-ALA. Results In this study, an ALA production strain of Escherichia coli was constructed by rational metabolic engineering and stepwise improvement. A metabolic strategy to produce ALA directly from glucose in this recombinant E. coli via both C4 and C5 pathways was applied herein. The expression of a modified hemA RS gene and rational metabolic engineering by gene knockouts significantly improved ALA production from 765.9 to 2056.1 mg/L. Next, we tried to improve ALA production by RGMS-directed evolution of eamA gene. After RGMS, the ALA yield of strain A2-ASK reached 2471.3 mg/L in flask. Then, we aimed to improve the oxidation resistance of cells by overexpressing sodB and katE genes and ALA yield reached 2703.8 mg/L. A final attempt is to replace original promoter of hemB gene in genome with a weaker one to decrease its expression. After 24 h cultivation, a high ALA yield of 19.02 g/L was achieved by 108-ASK in a 5 L fermenter. Conclusions These results suggested that an industrially competitive strain can be efficiently developed by metabolic engineering based on combined rational modification and optimization of gene expression.

Abstract Background Non-conventional yeasts hold significant potential as biorefinery cell factories for microbial bioproduction. Currently, gene editing systems used for these yeasts rely on antibiotic and auxotrophic selection mechanisms. However, the drawbacks of antibiotics, including high costs, environmental concerns, and the dissemination of resistance genes, make them unsuitable for large-scale industrial fermentation. For auxotrophic selection system, the engineered strains harboring auxotrophic marker genes are typically supplemented with complex nutrient-rich components instead of precisely defined synthetic media in large-scale industrial fermentations, thus lack selection pressure to ensure the stability of heterologous metabolic pathways. Therefore, it is a critical to explore alternative selection systems that can be adapted for large-scale industrial fermentation. Results Here, a novel glucose-dependent selection system was developed in a high pullulan-producing non-conventional strain A. melanogenum P16. The system comprised a glucose-deficient chassis cell Δpfk obtained through the knockout of the phosphofructokinase gene (PFK) and a series of chromosomal integration plasmids carrying a selection marker PFK controlled by different strength promoters. Utilizing the green fluorescent protein gene (GFP) as a reporter gene, this system achieved a 100% positive rate of transformation, and the chromosomal integration numbers of GFP showed an inverse relationship with promoter strength, with a customizable copy number ranging from 2 to 54. More importantly, the chromosomal integration numbers of target genes remained stable during successive inoculation and fermentation process, facilitated simply by using glucose as a cost-effective and environmental-friendly selectable molecule to maintain a constant and rigorous screening pressure. Moreover, this glucose-dependent selection system exhibited no significant effect on cell growth and product synthesis, and the glucose-deficient related selectable marker PFK has universal application potential in non-conventional yeasts. Conclusion Here, we have developed a novel glucose-dependent selection system to achieve customizable and stable multilocus chromosomal integration of target genes. Therefore, this study presents a promising new tool for genetic manipulation and strain enhancement in non-conventional yeasts, particularly tailored for industrial fermentation applications.

Abstract Background The need for addition of external electron donors such as ethanol or lactate impairs the economic viability of chain elongation (CE) processes for the production of medium-chain carboxylates (MCC). However, using feedstocks with inherent electron donors such as silages of waste biomass can improve the economics. Moreover, the use of an appropriate inoculum is critical to the overall efficiency of the CE process, as the production of a desired MCC can significantly be influenced by the presence or absence of specific microorganisms and their metabolic interactions. Beyond, it is necessary to generate data that can be used for reactor design, simulation and optimization of a given CE process. Such data can be obtained using appropriate mathematical models to predict the dynamics of the CE process. Results In batch experiments using silages of sugar beet leaves, cassava leaves, and Elodea/wheat straw as substrates, caproate was the only MCC produced with maximum yields of 1.97, 3.48, and 0.88 g/kgVS, respectively. The MCC concentrations were accurately predicted with the modified Gompertz model. In a semi-continuous fermentation with ensiled sugar beet leaves as substrate and digestate from a biogas reactor as the sole inoculum, a prolonged lag phase of 7 days was observed for the production of MCC (C6–C8). The lag phase was significantly shortened by at least 4 days when an enriched inoculum was added to the system. With the enriched inoculum, an MCC yield of 93.67 g/kgVS and a productivity of 2.05 gMCC/L/d were achieved. Without the enriched inoculum, MCC yield and productivity were 43.30 g/kgVS and 0.95 gMCC/L/d, respectively. The higher MCC production was accompanied by higher relative abundances of Lachnospiraceae and Eubacteriaceae. Conclusions Ensiled waste biomass is a suitable substrate for MCC production using CE. For an enhanced production of MCC from ensiled sugar beet leaves, the use of an enriched inoculum is recommended for a fast process start and high production performance.

Abstract To increase the production of biomass and astaxanthin from Haematococcus pluvialis to meet the high market demand for astaxanthin, this study recruited two typical and negligible phytohormones (namely resveratrol and catechol) for the stepwise treatments of H. pluvialis. It was found that the hybrid and sequential treatments of resveratrol (200 μmol) and catechol (100 μmol) had achieved the maximum astaxanthin content at 33.96 mg/L and 42.99 mg/L, respectively. Compared with the hybrid treatment, the physiological data of H. pluvialis using the sequential strategy revealed that the enhanced photosynthetic performance via the Calvin cycle by RuBisCO improved the biomass accumulation during the macrozooid stage; meanwhile, the excessive ROS production had occurred to enhance astaxanthin production with the help of NADPH overproduction during the hematocyst stage. Overall, this study provides improved knowledge of the impacts of phytohormones in improving biomass and astaxanthin of H. pluvialis, which shed valuable insights for advancing microalgae-based biorefinery.

The properties of the fuels determine the quality of the combustion process and implicitly the performance of the turbojet engine. The optimal heterogeneous combustion process of an aviation fuel is ensured by a stoichiometric ratio (fuel/fuel), a combustion temperature and a maximum loading degree of the combustion chamber. The article includes a numerical analysis instrumented with Gasturb software that highlights the influence of fuel quality and combustion process characteristics of a Rolls Royce Viper turbojet engine on its performance.

Abstract Background Schizochytrium sp. is commercially used for production of docosahexaenoic acid (DHA). Schizochytrium sp. utilizes the polyketide synthase complex (PKS) and a single type I fatty acid synthase (FAS) to synthesize polyunsaturated fatty acids and saturated fatty acids, respectively. The acyl carrier protein (ACP) domains of FAS or PKS are used to load acyl groups during fatty acids biosynthesis. Phosphopantetheinyl transferase (PPTase) transfers the pantetheine moiety from Coenzyme A to the conserved serine residue of an inactive ACP domain to produce its active form. Results In this study, in order to improve production and content of DHA, we decreased the expression of fas, strengthened the expression of the PKS pathway, and enhanced the supply of active ACP in Schizochytrium sp. ATCC20888. Weakening the expression of fas or disruption of orfA both led to growth defect and reduction of lipid yields in the resulting strains WFAS and DPKSA, indicating that both FAS and PKS were indispensable for growth and lipid accumulation. Although WFAS had a higher DHA content in total fatty acids than the wild-type strain (WT), its growth defect and low DHA yield hinders its use for DHA production. Overexpression of the orfAB, orfC, orfC-DH (truncated orfC), or ppt promoted DHA and lipid production, respectively. The yields and contents of DHA were further increased by combined overexpression of these genes. Highest values of DHA yield (7.2 g/L) and DHA content (40.6%) were achieved in a recombinant OPKSABC-PPT, ⁓56.5% and 15.3% higher than the WT values, respectively. Conclusions This study demonstrates that genetic engineering of the fatty acid biosynthetic pathways provides a new strategy to enhance DHA production in Schizochytrium.

Abstract Background Lignin is a highly abundant but strongly underutilized natural resource that could serve as a sustainable feedstock for producing chemicals by microbial cell factories. Because of the heterogeneous nature of the lignin feedstocks, the biological upgrading of lignin relying on the metabolic routes of aerobic bacteria is currently considered as the most promising approach. However, the limited substrate range and the inefficient catabolism of the production hosts hinder the upgrading of lignin-related aromatics. Particularly, the aerobic O-demethylation of the methoxyl groups in aromatic substrates is energy-limited, inhibits growth, and results in carbon loss in the form of CO2. Results In this study, we present a novel approach for carbon-wise utilization of lignin-related aromatics by the integration of anaerobic and aerobic metabolisms. In practice, we employed an acetogenic bacterium Acetobacterium woodii for anaerobic O-demethylation of aromatic compounds, which distinctively differs from the aerobic O-demethylation; in the process, the carbon from the methoxyl groups is fixed together with CO2 to form acetate, while the aromatic ring remains unchanged. These accessible end-metabolites were then utilized by an aerobic bacterium Acinetobacter baylyi ADP1. By utilizing this cocultivation approach, we demonstrated an upgrading of guaiacol, an abundant but inaccessible substrate to most microbes, into a plastic precursor muconate, with a nearly equimolar yields (0.9 mol/mol in a small-scale cultivation and 1.0 mol/mol in a one-pot bioreactor cultivation). The process required only a minor genetic engineering, namely a single gene knock-out. Noticeably, by employing a metabolic integration of the two bacteria, it was possible to produce biomass and muconate by utilizing only CO2 and guaiacol as carbon sources. Conclusions By the novel approach, we were able to overcome the issues related to aerobic O-demethylation of methoxylated aromatic substrates and demonstrated carbon-wise conversion of lignin-related aromatics to products with yields unattainable by aerobic processes. This study highlights the power of synergistic integration of distinctive metabolic features of bacteria, thus unlocking new opportunities for harnessing microbial cocultures in upgrading challenging feedstocks.

Abstract Background The aim of this study was to increase the accessibility and accelerate the breakdown of lignocellulosic biomass to methane in an anaerobic fermentation system by mechanical cotreatment: milling during fermentation, as an alternative to conventional pretreatment prior to biological deconstruction. Effluent from a mesophilic anaerobic digester running with unpretreated senescent switchgrass as the predominant carbon source was collected and subjected to ball milling for 0.5, 2, 5 and 10 min. Following this, a batch fermentation test was conducted with this material in triplicate for an additional 18 days with unmilled effluent as the ‘status quo’ control. Results The results indicate 0.5 – 10 min of cotreatment increased sugar solubilization by 5– 13% when compared to the unmilled control, with greater solubilization correlated with increased milling duration. Biogas concentrations ranged from 44% to 55.5% methane with the balance carbon dioxide. The total biogas production was statistically higher than the unmilled control for all treatments with 2 or more minutes of milling (α = 0.1). Cotreatment also decreased mean particle size. Energy consumption measurements of a lab-scale mill indicate that longer durations of milling offer diminishing benefits with respect to additional methane production. Conclusions Cotreatment in anaerobic digestion systems, as demonstrated in this study, provides an alternative approach to conventional pretreatments to increase biogas production from lignocellulosic grassy material.

Abstract Plastic consumption has increased globally, and environmental issues associated with it have only gotten more severe; as a result, the search for environmentally friendly alternatives has intensified. Polyhydroxyalkanoates (PHA), as biopolymers produced by microalgae, might be an excellent option; however, large-scale production is a relevant barrier that hinders their application. Recently, innovative materials such as carbon dots (CDs) have been explored to enhance PHA production sustainably. This study added green synthesized multi-doped CDs to Scenedesmus sp. microalgae cultures to improve PHA production. Prickly pear was selected as the carbon precursor for the hydrothermally synthesized CDs doped with nitrogen, phosphorous, and nitrogen–phosphorous elements. CDs were characterized by different techniques, such as FTIR, SEM, ζ potential, UV–Vis, and XRD. They exhibited a semi-crystalline structure with high concentrations of carboxylic groups on their surface and other elements, such as copper and phosphorus. A medium without nitrogen and phosphorous was used as a control to compare CDs-enriched mediums. Cultures regarding biomass growth, carbohydrates, lipids, proteins, and PHA content were analyzed. The obtained results demonstrated that CDs-enriched cultures produced higher content of biomass and PHA; CDs-enriched cultures presented an increase of 26.9% in PHA concentration and an increase of 32% in terms of cell growth compared to the standard cultures.

Abstract Background Manganese peroxidases (MnPs) are, together with lignin peroxidases and versatile peroxidases, key elements of the enzymatic machineries secreted by white-rot fungi to degrade lignin, thus providing access to cellulose and hemicellulose in plant cell walls. A recent genomic analysis of 52 Agaricomycetes species revealed the existence of novel MnP subfamilies differing in the amino-acid residues that constitute the manganese oxidation site. Following this in silico analysis, a comprehensive structure–function study is needed to understand how these enzymes work and contribute to transform the lignin macromolecule. Results Two MnPs belonging to the subfamilies recently classified as MnP-DGD and MnP-ESD—referred to as Ape-MnP1 and Cst-MnP1, respectively—were identified as the primary peroxidases secreted by the Agaricales species Agrocybe pediades and Cyathus striatus when growing on lignocellulosic substrates. Following heterologous expression and in vitro activation, their biochemical characterization confirmed that these enzymes are active MnPs. However, crystal structure and mutagenesis studies revealed manganese coordination spheres different from those expected after their initial classification. Specifically, a glutamine residue (Gln333) in the C-terminal tail of Ape-MnP1 was found to be involved in manganese binding, along with Asp35 and Asp177, while Cst-MnP1 counts only two amino acids (Glu36 and Asp176), instead of three, to function as a MnP. These findings led to the renaming of these subfamilies as MnP-DDQ and MnP-ED and to re-evaluate their evolutionary origin. Both enzymes were also able to directly oxidize lignin-derived phenolic compounds, as seen for other short MnPs. Importantly, size-exclusion chromatography analyses showed that both enzymes cause changes in polymeric lignin in the presence of manganese, suggesting their relevance in lignocellulose transformation. Conclusions Understanding the mechanisms used by basidiomycetes to degrade lignin is of particular relevance to comprehend carbon cycle in nature and to design biotechnological tools for the industrial use of plant biomass. Here, we provide the first structure–function characterization of two novel MnP subfamilies present in Agaricales mushrooms, elucidating the main residues involved in catalysis and demonstrating their ability to modify the lignin macromolecule.

Creatively integrating synthetic materials (semiconductors and electrodes) and microorganisms, the semi-artificial photosynthetic system (SAPS) couples the advantages of natural photosystems (high catalytic reaction selectivity) and artificial photosystems (excellent light-harvesting performance). This combination effectively overcomes the shortcomings of poor selectivity in artificial photosystems, bringing new opportunities for developing photosynthetic systems. It also provides a promising strategy for addressing the current energy crisis and environmental pollution. The design and selection of synthetic materials play a crucial role in this system, aiming to achieve efficient photon capture and electron transfer. This review begins by exploring the fundamental principles of SAPS, emphasizing the integration of materials and microorganisms and the factors that influence their interactions. It provides a critical analysis of the diverse compositional arrangements and systematically elucidates the foundational research methodologies employed in the investigation of SAPS. Grounded in their distinctive redox characteristics, it comprehensively surveys their recent applications in environmental remediation and sustainable energy production over the past years. Finally, reflections on future research are proposed, beginning with the challenges that limit the application of SAPS. Building on previous studies, the present review identifies the factors that limit SAPS and suggests potential avenues for future research. Additionally, this review delves into the environmental and economic policies and practical implications. In conclusion, by critically assessing the existing research landscape, delineating challenges, and charting future research directions, the present review aims to provide valuable insights for researchers and practitioners, guiding efforts toward advancing SAPS for enhanced environmental sustainability and economic feasibility.

In this study, we reviewed previous information regarding the effect of fossil fuel pricing intervention on the consumption of fossil fuels, air quality, and population health. In a rapid review, we searched and reviewed reports about the effect of fossil fuel pricing interventions on each or some of the following outcomes: fossil fuel consumption, concentrations of air pollutants, and mortalities or morbidities attributable to exposure to air pollutants. As part of our investigation, we also present the findings of an unpublished, original study that specifically estimated the effects of an elevated gasoline price in Iran's ten most populous cities. Pricing interventions were effective in reducing the consumption of fossil fuels, both in developing and developed countries. Price elasticity for transport gasoline was reported to be -0.227 and -0.715 for short- and long-term, respectively. Reductions in concentrations of air pollutants, especially NOx and particulate matter, were reported in several studies. This review study demonstrates the effects of escalating fossil fuel prices on reducing consumption, air pollution, and mortalities and morbidities attributable to air pollution. Considering the external costs of fossil fuels through environmental, climate, traffic congestions and accidents, and population health, the real costs of fossil fuels are much higher than their retail price. Pro-rich policies of subsidizing fossil fuels should be replaced by alternative policies that support clean public transport, which is suitable for population health, environment, and equity.

As climate change intensifies and the need to reduce human-caused emissions becomes more urgent, transitioning to a bio-based economy is essential. This paper explores the diverse industrial applications of plant oils as sustainable alternatives to petroleum-based products, including their use in food, polymers, lubricants, surfactants, pesticides, emollients, and biofuels. This review delves into biosynthetic pathways, detailing the key enzymes and processes involved in the synthesis of triacylglycerol. It thoroughly discusses how genetic and metabolic engineering can not only increase oil yields but also modify fatty acid compositions to better meet industrial requirements. By understanding genetics and utilizing advanced biotechnologies, the oil content and quality of plant sources can be significantly enhanced, aligning with both sustainability goals and industrial demands. This paper provides a comprehensive overview of the current uses and genetic engineering of plant oil production, proposing innovative strategies such as utilizing oils from biomass or cultivating non-edible oil crops. These approaches aim to establish a sustainable industrial system, reduce reliance on fossil fuels, and promote the growth of an environmentally responsible bio-based economy. Additionally, the review highlights future directions, examining the economic implications and environmental benefits of adopting plant oils across various sectors and positioning them as pivotal to achieving an eco-friendly, bio-based economy.

The escalating global demand for protein and the imperative to meet sustainable development goals have driven the emergence of biotransformation platforms, with methanotrophs showing significant potential in this field. In this paper, the metabolism, nutritional requirements, cultivation strategies, and bioreactors of methanotrophs are reviewed. Integrating upstream and downstream technologies is also advocated to advance the development of methanotroph biotransformation platforms toward a circular economy model. The advancements in utilizing biogas as a viable carbon source and wastewater as a nitrogen source are discussed, emphasizing the need for detailed quality control and safety assessments to ensure the suitability of single-cell protein as animal feed. In general, by integrating advanced nutrient recovery technologies to define new process routes, methanotroph biotransformation platforms can bring better environmental benefits by reducing carbon emissions and saving resources. Shifting to renewable energy is crucial for achieving environmental sustainability. By using renewable energy to power microbial fermentation, biomass dehydration, and waste recycling, the platform can offset high energy consumption and attain significant market competitiveness with traditional protein sources.

This paper presents the findings of a study of the pelleting process of pine sawdust with the addition of waste in the form of potato pulp (as a natural binder), in the context of producing fuel pellets. The process of pelleting was carried out for sawdust and for a mixture of sawdust and potato pulp (10, 15, 20, and 25%). The highest moisture content was obtained in the case of pellets produced from a mixture of straw with a 25% potato pulp content, i.e., 26.54% (with a potato pulp moisture content of 85.08%). Increasing the potato pulp content in a mixture with sawdust from 10 to 25% reduced the power demand of the pelletizer by approx. 20% (from 7.35 to 5.92 kW). The obtained density values for pellets made from a mixture of sawdust and potato pulp (over 1000 kg∙m−3) with a potato pulp content of 10% make it possible to conclude that the obtained pellets meet the requirements of the ISO 17225-2:2021-11 standard. Increasing the potato pulp content from 0 to 25% caused a slight decrease in the heat of combustion, i.e., from 20.45 to 20.32 MJ∙kg−1, as well as in the calorific value, from 19.02 to 18.83 MJ∙kg−1 (both for dry sawdust matter and the mixture). The results of the laboratory tests were used to verify the densification process of mixtures of sawdust and potato pulp under industrial conditions at the PANBAH plant, using pelleting mixtures with a 5%, 10%, and 25% content of potato pulp. Industrial research also confirmed that the use of the addition of potato pulp in a mixture with sawdust significantly reduces the power demand of the pelletizer, and it also increases the kinetic strength of the obtained pellets. [ABSTRACT FROM AUTHOR]

The economy of the Russian Federation is aimed at developing a fuel and energy complex that uses environmentally friendly energy, which corresponds to the global trend of reducing emissions of harmful substances into the atmosphere during the production of various types of products. Decarbonization is one of the biggest challenges of modern society. To solve this problem, renewable energy sources are being actively introduced, as well as various types of fuel, the combustion of which produces a minimum content of emissions. Among them, we can highlight the fuel that has the greatest prospects; this is hydrogen, a fuel with the highest energy content, reaching a value of 120 MJ/kg. Unlike renewable energy sources, the practice of which in a number of countries has caused a crisis in the reliability of the energy system, hydrogen technologies make it possible to achieve the task of decarbonization with minimal impact on the environment at all stages: production, transportation, combustion, without compromising reliability. The main problems of mass introduction of hydrogen technologies are the difficulty in obtaining, transporting and storing hydrogen fuel. Following the signing of hydrogen strategies, most developed countries are considering using hydrogen as a vehicle fuel. Hydrogen transport, unlike electric transport, is not limited by range, but the high cost of hydrogen transport and the lack of refueling infrastructure hinder the development of this type of technology. Currently, the most common fuel cell system is FCV (fuel cell vehicle). The article presents the concept of hydrogen refueling, taking into account different technologies for the production of hydrogen fuel. Hydrogen must be stored at a filling station at a pressure of 300–800 bar, in a gaseous or liquid state. An analysis of the cost of construction and subsequent operation of hydrogen filling stations revealed criteria for the economic efficiency of their implementation depending on the amount of fuel consumed and storage methods. [ABSTRACT FROM AUTHOR]

This paper presents an innovative mathematical model of solid fuel gasification, which is not described in the available literature. The calculation of the components of the heterogeneous phase (including both solid and gaseous phases) as well as the calculation of the homogeneous phase (only gaseous components) is based on the balance of the total amounts of carbon, oxygen, hydrogen, and nitrogen entering the reactor space. Additionally, this paper introduces a new method for calculating the composition of the gaseous phase, based on reducing the heterogeneous mixture (composed of solid and gaseous phases) to a homogeneous gaseous phase. This approach to calculating the gaseous phase composition in the solid fuel gasification process has not been found by the authors in the cited literature. This paper also presents a model for calculating the heterogeneous and gaseous phases using the number of moles that participate in the assumed chemical reactions of the solid fuel gasification process. This approach to calculating the composition of the heterogeneous and gaseous phases of the solid fuel gasification process is also not represented in the cited literature. For comparison with the literature data, municipal solid waste (MSW) and cashew nut shell (Cashew Shell Char (CNSC)) were used as fuels in the calculation of gasification composition. The results of the calculation of the gaseous phase composition using the model presented in the paper show good agreement with the data from the literature. The calculation of the composition of the heterogeneous mixture during the steam gasification of MSW (α = 0.4) shows the presence of a solid phase (carbon) up to approximately 735 °C. At that temperature, the synthetic gas contains only gaseous components: CO = 33.10%, H2 = 52.70%, CH4 = 2.54%, CO2 = 4.97, H2O = 5.93% and N2 = 0.76%. Increasing the temperature above 735 °C eliminates the solid phase from the equilibrium mixture. The literature data on solid fuel gasification generally do not consider the proportion of the solid phase (carbon) in the equilibrium mixture. To satisfy the material balance at the input and output of the gasification reactor, it is necessary to determine the proportion of the solid phase (carbon) in the equilibrium mixture. Since the proportion of the solid phase (carbon) in the heterogeneous equilibrium mixture can only be determined through measurement, the development and application of a mathematical model in engineering practice is of great importance, so this developed model can be considered a useful tool for simulating the influence of process parameters on gas characteristics. [ABSTRACT FROM AUTHOR]

This study presents the results of a combined dendrological, macrobotanical, and dung spherulite analysis of flotation samples collected from Bronze Age, Late Assyrian, and post-Assyrian contexts at the site of Ziyaret Tepe, located on the southern bank of the Tigris River in southeastern Anatolia. The results of this study show shifting fuel resource exploitation between pre-urbanized phases of the site (ca. 3000–1600 BCE), the urbanized Late Assyrian occupation (882–611 BCE), and the ruralized post-Assyrian (ca. 611 BCE–1500 CE) re-occupations of the site. During the Late Assyrian period, Ziyaret Tepe is thought to have been the location of the city of Tušhan, an important provincial capital of the Neo-Assyrian empire. Evidence for local deforestation near the Tigris River and expanding reliance on dung fuel use during this period indicate overexploitation of fuel resources as larger populations and extractive imperial economic policies placed heavier pressure on local land use. Qualitative dendrological data provides evidence for the intensification of fuelwood harvesting during this period, while textual evidence documented an expansive program of timbering to the north of the site intended to fuel imperial construction projects in the Assyrian heartland. Following the abandonment of Tušhan and the collapse of the Neo-Assyrian empire, local fuel resource exploitation during subsequent occupations of the site shifted towards the direct management of wood fuel resources and increasing reliance on rural pastoralism. [ABSTRACT FROM AUTHOR]

This study introduces a simple, cost-effective, and rapid bismuth electrode-square-wave voltammetry method for determining the total sulfur content in automotive gasoline. Optimal conditions for the developed electrode, including various Bi ion concentrations, deposition times, and potentials, were established on a glassy carbon electrode. The results demonstrated that the highest response was achieved when the bismuth electrode was placed in an acetate buffer and a methanol:toluene (1:1 v/v) solvent. The method was validated with and without a 30-second electro-preconcentration step. The voltammetric method in conjunction with the preconcentration step exhibited a sensitivity of 571.81 nA mg L−1, a limit of detection (LOD) of 0.02 mg L−1, and a limit of quantification (LOQ) of 0.08 mg L−1. Without the preconcentration step, the method yielded a sensitivity of 421.89 nA mg L−1, an LOD of 0.03 mg L−1, and an LOQ of 0.11 mg L−1. The developed method was applied to quantify commercial fuel samples. The results showed that the electrochemical technique yielded a similar total sulfur content to that measured by the standard ASTM D2622 method, with an error of less than 7.5%. Moreover, the method proposed in this study had lower LOD and LOQ limits, meeting the EURO5 and EURO6 regulations. [ABSTRACT FROM AUTHOR]

Plastic waste is utilized aggressively for food, product packaging, cosmetics, toys, clothes, and even furniture. As a result, discarded plastic as a waste has grown uncontrollably worldwide, most of it ending up as landfill. With increasing concern, researchers have made efforts to convert this plastic waste into a more useful product. Along these lines, this study focuses on producing 10 tons of diesel per day through fast pyrolysis at 450 °C in the fluidized bed reactor for a feed rate of 3000 kg of plastic waste per hour. The production was simulated in Aspen HYSYS V11 to ensure the desired yield. Further, a detailed economic analysis is carried out to estimate the return on investment and total cost per year, as well as the payback period and the profit for different scenarios. [ABSTRACT FROM AUTHOR]

This paper presents a framework for energy, exergy utilization, and economic analysis of industrial steam boiler system in Nigerian Bottling Company (NBC), Enugu, Nigeria. The study was carried out by an investigative approach in which all other parameters were kept constant, and a particular one was varied, and the desired quantity measured. The results of the effects of burner rotary cup speed and fuel nozzle sizes on emissions show that for boiler having liquid fuel nozzle sizes 3mm, 4mm and 6mm and with constant fuel inlet temperature of 82°C were analysed. Nozzle size of 4mm diameter with burner rotary cup operating at speed of 2920rev/min to 3200rev/min generated minimum emission while burning fuel oil of 82°C with excess air of 12.36%. Similarly, nozzle size of 6mm with rotary cup burner operating between 3950rev/min to 4400rev/min at 12.36 % excess air generated no emission of CO and NOx. It was concluded that the combustor yielded the highest energy efficiency of 99.8% while the heat exchanger gave the lowest energy efficiency of 94% when run on both fuel oil and natural gas. This improved efficiency translates to a savings of approximately 89 million naira annually for a boiler operating at 46% availability yearly. [ABSTRACT FROM AUTHOR]

The use of depressant additives is the most effective and cost-effective way to improve the low-temperature properties of diesel fuels, like the cloud point, cold filter plugging point and pour point. However, the effectiveness of depressant additives depends on the composition of the diesel fuel and the content of certain groups of hydrocarbons in it. In this work, the effect of adding individual hydrocarbons of various groups and structures on the effectiveness of depressant additives is studied. This study is carried out on model aromatic (toluene, tetralin) and n-paraffin hydrocarbons (cetane, heptadecane, heneicosane, docosane) in various concentrations. It is shown that the most negative effect on the depressant additives' effectiveness is due to the content of the most polar aromatic hydrocarbons and light n-paraffins in the composition of diesel fuel, and the most positive effect is exerted by the content of heavy n-paraffins in small quantities. It is proposed to involve small concentrations (1–3% vol.) of heavy n-paraffin hydrocarbons (heneicosane, docosane) to increase the effectiveness of the depressant additive. It has been established that for the more effective action of the depressant, it is necessary to take into account the content and structure of individual hydrocarbons in the diesel fuel's composition. [ABSTRACT FROM AUTHOR]

Waste to energy conversion routes can contribute to solving energy poverty and waste disposal problems while improving farmers' incomes by creating tradable value-added products. This study explored compositing waste paper and biogas digestate-derived char to produce fuel briquettes as a waste to energy conversion route. The objective was to optimize fuel and mechanical properties of derived briquettes. Response surface methodology was employed with independent variables of waste-paper mass, compression force, and drying time while ash content, higher heating value (HHV), density, compressive strength, and moisture content were the response variables. Linear models best fit the responses of HHV, compressive strength, and moisture content. Quadratic models best fit ash content and bulk density responses. Waste-paper mass had the most significant influence on briquettes' ash content, HHV, moisture content, and bulk density. Waste paper to digestate mass ratio of 0.3, compression force 1531 N, and drying time 11 days were found to be the optimum production conditions resulting into ash content of 22.7% db, HHV 14.7 MJ/kg, bulk density 562.7 kgm−3, compressive strength 9.9 N mm−2, and moisture content 5.5% wet basis (wb). Briquettes developed at optimum conditions exhibited drop test strength of 93%. Formulated briquettes had thermal efficiency of 52% compared to eucalyptus wood 31% and eucalyptus charcoal 36%, as well as a lower specific fuel consumption of 47 g/l compared to digestate char briquette and eucalyptus wood with 162 and 80 g/l respectively. If these briquettes replaced wood and its derived charcoal, cost savings of US$328.5 and US$216.23 would be realized per ton of the respective fuel foregone. [ABSTRACT FROM AUTHOR]

The aim of this research is to determine the design of a solar cell power generation system for utilizing fuel on ships at PT. Universal Manunggal Chakra. In this research, the type of research used is Research and Development. Seeing these things, researchers are interested in developing a solar cell power generation system to supply electricity on ships and applying a solar cell power generation system to supply electricity on ships. The results of the research state that the results of the manufacture and development of a prototype solar cell power generator can be concluded that the product is suitable, so it can be applied on ships. This can be proven from the test results by having a percentage of 96.25% in the appropriate category, so that the power generator prototype can supply electricity to the diesel generator on the MT.Hendropriyono III ship. [ABSTRACT FROM AUTHOR]

Multicropping can solve energy use and GHG balance problems, but the emergence, development, and productivity of such mixed crops are at risk due to the uneven distribution of precipitation. For this reason, investigations were performed at the Experimental Station of Vytautas Magnus University, Lithuania. Single maize crops were compared with Crimson/red clover, Persian clover, and alfalfa intercropped maize. The objective of this study was to evaluate the main energy indices and GHG balance of legume intercropped maize cultivated in humid and arid vegetative conditions. The results showed that, under arid conditions, the quantity of intercrop biomass was about four times lower than that under humid conditions. Humid conditions were less suitable for maize and resulted in about 3–5 t ha−1 less dried biomass from intercrops and about 6 t ha−1 less biomass in single crops than in arid conditions. Due to the higher yield of maize biomass in the arid season, better energy indicators of crops were obtained in arid than humid conditions. The difference between net energy was about 122–123 MJ ha−1 in all treatments, except for the maize crop with intercropped alfalfa, where the difference was 62 MJ ha−1. All tested technologies were environmentally friendly; the CO2 equivalent varied between treatments from 804 to 884 kg ha−1. The uneven distribution of precipitation during the vegetative season provides insight into the improvement of intercropping technologies. Sowing intercrops at the same time as maize could improve their germination but increase the problem of weed spread. [ABSTRACT FROM AUTHOR]

The maritime industry needs sustainable, low-emission fuels to reduce the environmental impact. Ammonia is one of the most promising alternative fuels because it can be produced from renewable energy, such as wind and solar. Furthermore, ammonia combustion does not emit carbon. This review article covers the advantages and disadvantages of using ammonia as a sustainable marine fuel. We start by discussing the regulations and environmental concerns of the shipping sector, which is responsible for around 2% to 3% of global energy-related CO2 emissions. These emissions may increase as the maritime industry grows at a compound annual growth rate of 4.33%. Next, we analyze the use of ammonia as a fuel in detail, which presents several challenges. These challenges include the high price of ammonia compared to other fossil fuels, the low reactivity and high toxicity of ammonia, NOx, and N2O emissions resulting from incomplete combustion, an inefficient process, and NH3 slipping. However, we emphasize how to overcome these challenges. We discuss techniques to reduce NOx and N2O emissions, co-combustion to improve reactivity, waste heat recovery strategies, the regulatory framework, and safety conditions. Finally, we address the market trends and challenges of using ammonia as a sustainable marine fuel. [ABSTRACT FROM AUTHOR]

The use of agroforestry biomass provides several advantages, both from an environmental point of view, in terms of the mitigation of global warming, and in terms of a circular economy for agricultural or agroforestry companies that reuse pruning residues as a source of energy. However, even if the use of energy pellets resulting from the pruning residues of various agroforestry species has excellent potential for the valorization of agricultural by-products, the physicochemical characteristics of these pellets have been scarcely studied by the scientific community. In this context, this study aims to assess the valorization potential of various lignocellulosic material residues produced during agroforestry activities. The objectives of the study include evaluating the chemical and physical characteristics of pellets produced with different mixtures of agroforestry biomass (olive, citrus, black locust, poplar, paulownia, etc.) in order to determine the optimal pellet blend from an energy and physicochemical perspective. The results of this study demonstrate that this comprehensive analysis provides valuable information on the optimization of biomass mixtures for better energy valorization, addressing both compositional and combustion-related challenges. In fact, it is observed that the addition of citrus and olive biomass to the various mixtures increases their energy potential. Furthermore, all of the pellets analyzed are found to possess an adequate and useful durability index (PDI) for their handling during storage and transport operations. This study demonstrates that olive and citrus pruning residues can be used to improve biomasses that have poor suitability in energetic, physical, and chemical terms. Further studies could be useful to understand which specific interaction mechanisms have an influence on emissions in order to optimize mixtures using different biomass sources for sustainable energy production. [ABSTRACT FROM AUTHOR]

In the present research, the open-source WRF-SFIRE model has been used to carry out surface forest fire spread forecasting in the North Sikkim region of the Indian Himalayas. Global forecast system (GFS)-based hourly forecasted weather model data obtained through the National Centers for Environmental Prediction (NCEP) at 0.25 degree resolution were used to provide the initial conditions for running WRF-SFIRE. A landuse–landcover map at 1:10,000 scale was used to define fuel parameters for different vegetation types. The fuel parameters, i.e., fuel depth and fuel load, were collected from 23 sample plots (0.1 ha each) laid down in the study area. Samples of different categories of forest fuels were measured for their wet and dry weights to obtain the fuel load. The vegetation specific surface area-to-volume ratio was referenced from the literature. The atmospheric data were downscaled using nested domains in the WRF model to capture fire–atmosphere interactions at a finer resolution (40 m). VIIRS satellite sensor-based fire alert (375 m spatial resolution) was used as ignition initiation point for the fire spread forecasting, whereas the forecasted hourly weather data (time synchronized with the fire alert) were used for dynamic forest-fire spread forecasting. The forecasted burnt area (1.72 km2) was validated against the satellite-based burnt area (1.07 km2) obtained through Sentinel 2 satellite data. The shapes of the original and forecasted burnt areas matched well. Based on the various simulation studies conducted, an operational fire spread forecasting system, i.e., Sikkim Wildfire Forecasting and Monitoring System (SWFMS), has been developed to facilitate firefighting agencies to issue early warnings and carry out strategic firefighting. [ABSTRACT FROM AUTHOR]

2-methylfuran is a significant organic chemical raw material which can be produced by hydrolysis, dehydration, and selective hydrogenation of biomass hemicellulose. 2-methylfuran can be converted into value-added chemicals and liquid fuels. This article reviews the latest progress in the synthesis of liquid fuel precursors through hydroxyalkylation/alkylation reactions of 2-methylfuran and biomass-derived carbonyl compounds in recent years. 2-methylfuran reacts with olefins through Diels-Alder reactions to produce chemicals, and 2-methylfuran reacts with anhydrides (or carboxylic acids) to produce acylated products. In the future application of 2-methylfuran, developing high value-added chemicals and high-density liquid fuels are two good research directions. [ABSTRACT FROM AUTHOR]

One of the most important energy sources is non-renewable sources, including fossil fuels, the release of which causes many harmful consequences, including respiratory diseases, growth disorders, etc. On the other hand, renewable energies, including water, wind, sun, etc., are sustainable energy sources and compared to traditional fossil fuels, they have less adverse environmental effects due to the minimal emission of greenhouse gases. Due to the need to use renewable energy to reduce greenhouse gas emissions and combat climate change, the widespread use of these resources will bring about sustainable development. Therefore, creating the necessary infrastructure to use renewable energy as an important solution plays a key role in preserving natural resources. The purpose of this study is to review green and renewable fuels; Their sources, applications, advantages, and limitations. In this narrative review study, review articles, research articles, and cross-sectional descriptions were published until the beginning of February 2023 in English and Persian related to green and renewable fuels; Sources, applications, advantages, and limitations were investigated. These articles were searched in ScienceDirect, PubMed, Google Scholar, Web of Science, Scopus, and SID databases, using keywords such as renewable energy, fossil fuel, green fuel, and nonrenewable energy with the aim of better understanding green fuels; Their sources, application, advantages, and limitations were obtained. After searching the databases with the mentioned keywords, 78 articles were included in the study. After removing duplicate articles, studying the abstract, and finally the full text of the articles, 35 related articles were included in the study. Endnote X7 resource management software was also used to organize, study titles and abstracts, and identify duplicate articles. Green fuel is a non-toxic fuel that is essentially free of sulfur and aromatic compounds and is produced through various technologies such as biological and thermochemical processes. All the reviewed articles in the direction of producing green fuels such as biodiesel, natural gas, and hydrogen have pointed to the reduction of greenhouse gas emissions, improvement of air quality, stability of combustion in engines with dual fuel performance, and reduction of the negative effects of air pollution on health. Green fuel production is promising, but it faces limitations and challenges such as the need for land, water, and other resources, which can lead to changes in land use patterns, deforestation, and biodiversity loss. Also, the costs of producing biofuels depend on important factors such as raw materials, land, agricultural inputs, subsidies, and production technology. Biofuels are usually more expensive than fossil fuels and their production requires initial investment and maintenance costs. Considering the limitations and challenges of producing or using green fuel, using these renewable energy sources requires environmental planning and policy. Green fuels and renewable energy sources have emerged as promising solutions to deal with the environmental challenges caused by traditional fossil fuels. In general, green fuels offer a glimpse of a more sustainable future. However, their environmental effects need to be carefully investigated. Hence, a comprehensive understanding of diverse green fuel production methods and renewable energy technologies, along with their potential ecological impacts, is necessary to ensure the alignment of these alternative energy sources to achieve sustainable development. [ABSTRACT FROM AUTHOR]

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In this study we synthesized and characterized Ni/AC (Activated Carbon) systems. AC was obtained through pyrolysis of golden rod's dried biomass. Ni nanoparticles were deposited on AC's surface using a wet impregnation method from a nickel nitrate solution. SEM, MP-AES and DSC-TGA techniques were used for surficial and structural characterization, while ash content was made to check mineral ingredients input. The DSC-TGA study revealed that all carbons show good thermal stability up to 900 °C, which is far above operating temperatures in the methanation process. For all three carbons the BET isotherms were made as well. They show that in most cases the carbon's surface is well developed and can adsorb decent amounts of metal. MP-AES helped to evaluate the efficiency of the impregnation process, which reached 76 mg of Ni per 1 g of carbon. The SEM-EDS study showed good distribution of Ni nanoparticles across AC's surface. We also made a comparison of our systems to similar materials from other works. [ABSTRACT FROM AUTHOR]

The present study aims to assess the contribution of Indian households to the increase in carbon footprint. Hence, this cross-sectional study was conducted in the Kalyani subdivision of Nadia district, West Bengal, India. Data were collected from 610 households, comprising 299 rural and 311 urban households, to analyse energy consumption patterns for various purposes. To summarize the dependent and continuous data, descriptive statistics were employed, while for inferences, independent sample t-test, Pearson correlation and regression were used. A significant difference was observed in total annual household carbon footprint between the urban and rural households due to varied energy consumption (t = 15.60, p < 0.05). The urban households were emitting twice (2325.20 kgCO2e) as much as the rural ones (1125.77 kgCO2e). It can also be inferred that emission was determined by the increase in household size, income, and improvement in the standard of living. Thus, in addition to several determinants, a complex cultural system, social practices, and awareness of green consumerism should also be incorporated and studied through an interdisciplinary approach to reduce the overall household carbon footprint. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glass fiber wind turbine blades (WTBs) can provide raw material to produce cement. • Glass fiber WTBs can serve as fuel and replace coal to produce cement. • High boron in some glass fiber WTBs might limit replacement rates. • Combustion of fossil-fuel polymer in WTBs can slightly reduce plant CO 2 emissions. • Glass fiber wind turbine blades are compatible with the cement production process. The objective of this paper is to evaluate the feasibility of co-processing wind turbine blade (WTB) material in cement manufacturing to provide an end-of-life means to divert the solid waste of decommissioned WTBs from landfills. Many WTBs consist primarily of glass fiber reinforced thermoset polymers that are difficult to recover or recycle. Portland cement is produced world-wide in large quantities, requiring immense quantities of raw materials (mostly calcium oxide and silicon oxide) and kiln temperatures approaching 1,450 °C. This work contributes analyses of WTB material composition, and predicts the energy provided through the combustible components of the WTBs and raw material contributions provided by incorporating the incombustible components of the WTBs to produce cement. Approximately 40 to 50 % of the WTB material will contribute as fuel to cement production, and approximately 50 to 60 % of the WTB material is expected to be incombustible. One tonne of WTB material can displace approximately 0.4 to 0.5 tonne of coal, while also contributing approximately 0.1 tonne of calcium oxide and 0.3 tonne of silicon oxide as raw material to the cement production process. The glass fiber WTB tested had an average boron content of 4.5 % in the ash. The effects of this high boron content on the cement and its production process should be evaluated. Co-processing WTBs in cement plants will slightly reduce combustion-related CO 2 emissions due to avoided calcination. It seems feasible to co-process glass-fiber reinforced WTBs in cement production as WTBs provide suitable raw materials and compatible fuel for this process. [ABSTRACT FROM AUTHOR]

Plastics have become integral to modern life, playing crucial roles in diverse industries such as agriculture, electronics, automotive, packaging, and construction. However, their excessive use and inadequate management have had adverse environmental impacts, posing threats to terrestrial and marine ecosystems. Consequently, researchers are increasingly searching for more sustainable ways of managing plastic wastes. Pyrolysis, a chemical recycling method, holds promise for producing valuable fuel sustainably. This study explores the process of the pyrolysis of plastic and incorporates recent advancements. Additionally, the study investigates the integration of reforming into the pyrolysis process to improve hydrogen production. Hydrogen, a clean and eco-friendly fuel, holds significance in transport engines, power generation, fuel cells, and as a major commodity chemical. Key process parameters influencing the final products for pyrolysis and in-line reforming are evaluated. In light of fossil fuel depletion and climate change, the pyrolysis and in-line reforming strategy for hydrogen production is anticipated to gain prominence in the future. Amongst the various strategies studied, the pyrolysis and in-line steam reforming process is identified as the most effective method for optimising hydrogen production from plastic wastes. [ABSTRACT FROM AUTHOR]

Solar energy is an attractive alternative to fossil fuels (electricity and coke) for petroleum products generation. A solar-integrated binary chemical cracking of heavy oil system integrates solar energy into oil processing for carbon neutrality，in which pyrolysis and electrolysis benefit heavy oil conversion and hydrogen storage. This system has been studied in terms of solar chemical engineering, electrolyte engineering and electrode engineering. The results show improved hydrogen yield and cracking rate of heavy oil and a significant reduction in the operating temperature compared to catalytic cracking. The performance of molten salt electrolytes is as follows: binary NaOH–KOH > ternary KCl–LiCl + NaOH > ternary KCl–LiCl + NaHCO 3. In electrode engineering, the electro-catalytic electrodes are in an order of Inconel 718> Ni > Incoloy 825 electrodes in the cracking rate, Ni > Inconel 718>Incoloy 825 electrodes in the hydrogen yield, and Incoloy 825>Inconel 718>Ni electrodes in the ability, for sustainable and stable efficient production. [Display omitted] • Solar binary chemical cracking can efficiently upgrade fuel and abundantly generate hydrogen. • Solar binary energy is integrated into oil processing to replace fossil energy. • The starting reaction temperature is 230 °C, lower than the catalytic cracking. [ABSTRACT FROM AUTHOR]

General interest in the deployment of molten salt reactors (MSRs) is growing, while the available data on uranium-containing fuel salt candidates remains scarce. Thermophysical data are one of the key parameters for reactor design and understanding reactor operability. Hence, filling in the gap of the missing data is crucial to allow for the advancement of MSRs. This study provides novel data for two eutectic compositions within the NaF-KF-UF4 ternary system which serve as potential fuel candidates for MSRs. Experimental measurements include their melting point, density, fusion enthalpy, and vapor pressure. Additionally, their boiling point was extrapolated from the vapor pressure data, which were, at the same time, used to determine the enthalpy of vaporization. The obtained thermodynamic values were compared with available data from the literature but also with results from thermochemical equilibrium calculations using the JRCMSD database, finding a good correlation, which thus contributed to database validation. Preliminary thoughts on fluoride salt reactor operability based on the obtained results are discussed in this study. [ABSTRACT FROM AUTHOR]

The Non-thermal plasma has a wide range of applications in different areas. In this study, the oxidation of a model fuel containing organo-sulfur compounds (benzothiophene and dibenzothiophene) was investigated using plasma. The process involved ozone generation through dielectric barrier discharge, followed by extraction using acetonitrile. The results demonstrated the efficient oxidation and removal of dibenzothiophene and benzothiophene by non-thermal plasma. The desulfurization efficiency reached 93.78% under the optimum conditions, including a voltage of 11Kv, temperature of 50ºC, duration of 4 hours, and a flow rate of 75 ml/min. [ABSTRACT FROM AUTHOR]

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell (SOFC) technology is the insufficient stack lifespan caused by a variety of degradation mechanisms, which are associated with cell components and chemical feedstocks. Cell components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions, whereas the latter regards impurities in feedstocks of oxidant (air) and reductant (fuel). This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in SOFCs. The discussion focuses on using thermodynamic analysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr, CO2, H2O, and SO2 and in the anode by species such as S (or H2S), SiO2, and P2 (or PH3). The author hopes the presented fundamental insights can provide a theoretical foundation for searching for better technical solutions to address the critical degradation challenges. [ABSTRACT FROM AUTHOR]

This paper provides a detailed literature review of the environmental implications of vehicle platooning, a topic gaining significant attention in transportation. While previous reviews have focused on the safety, planning, fuel economy, and microsimulation aspects of platooning, this paper delves into environmental aspects. It identifies a lack of research adopting a holistic approach to transport and environmental benefits and emphasizes the need for further research to enhance vehicle efficiency and improve air quality and health conditions. This study traces the historical evolution of platooning, highlighting the shift in research focus over the decades. It advocates for more research on platooning's environmental aspects, particularly pollutant emissions and air quality. The primary contributions of this work are threefold and include the following: firstly, it delineates simulation methodologies for platooning and the associated pollutant emissions; secondly, it offers a critical assessment of the existing literature on vehicle emissions, fuel consumption, and energy savings; and thirdly, it illuminates the prospective research challenges within the specialized domain of vehicle platooning. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic and the ongoing Russia-Ukraine war had severe implications for global food security and nutrition. It was feared that food systems would be impacted negatively, especially food, seed, fertilizer, and fuel quantities required for agricultural production. The study aimed to ascertain the extent to which calls to action by AU policy organs, as well as recommendations by experts, to mitigate possible effects of the COVID-19 pandemic, were implemented at the national level across three of the five regional economic communities and whether they yielded any tangible impacts. The study conducted a desk review of literature and key informant interviews in 18 African countries. We found a wide range of varia­tions in terms of country responses to the pan­demic. Countries in the East African Community focused more on expanding targeted social protec­tion programs, Economic Community of West African States countries focused more on support­ing smallholder farmers and digital agriculture, and the Southern African Development Community focused on budgetary stimulus packages. We found a lack of coherence in responding to the crisis within each region to improve the supply and dis­tribution of food, seed, fertilizer, and fuel; thus, necessitating an immediate and aggressive imple­mentation of strategies aligned with continental and regional policy resolutions and recommenda­tions.

The initiation of the first crack mainly determines the criteria for glass failure. However, the extended consequences of cracking, with the formation of multiple cracks merging, result in fallout conditions under varying thermal loads that become more critical. Point-supported glass arrangements are globally used in high-rise and energy-efficient buildings for architectural ingenuity aimed at a low budget. However, the formation of cracks due to thermal load resulting in glass breakage could infuriate the overall fire dynamics of the enclosed area. Therefore, experimental study and prediction of glass failure become very crucial. The present experimental study focuses on finding the most critical parameter that may quantify the cause of glass failure and further breakage in fallout conditions under varying thermal loads. 45 experiments were carried out on float glass of 300 × 300 mm2 with 4 mm, 6 mm, 8 mm, 10 mm, and 12 mm with continuous fuel supply arrangements. Critical parameters analysed were the time of crack initiation, glass temperature at the time of cracking, maximum temperature difference at glass failure, and thermal strain caused by the temperature difference on the glass surface. The range of minimum and maximum temperature difference recorded on the glass surface for the present study was between 30–35°C and 55–60°C at the breakage time for all the experiments. The Maximum temperature difference measured was 56.99°C on the 12 mm glass surface, and the corresponding maximum thermal strain found was 482 × 10−6 mm/mm. The maximum heat release rate was found to be approximately 200 kW. Maximum heat flux was found in the range of 10.33 kW/m2 to 21.14 kW/m2. A correlation was also developed using the least square method for all the thicknesses, which is well correlated with the glass thickness per unit length.

The direct utilization of heavy and extra-heavy crude oils presents a formidable challenge due to their inherent physical and chemical properties such as high C/H ratio, extremely high viscosity and density, low APIo, super low mobility, high asphaltene and impurity (Fe, Ni, Co, S, N, etc.) contents. To tackle these problems cost-effectively, we have proposed and established a novel technique, distinct from conventional hydrotreating, for catalytic partial upgrading of extra heavy crudes with co-fed methane and a multi-functional catalyst. This technique has been further optimized using lab-scale batch reactors (100 mL, 300 mL), bench-scale and pilot-scale fixed bed reactors with their processing capacity of 250 mL/day and 20 L/day, respectively. The feasibility, stability, and profitability of this technique have been successfully verified using all these facilities and a wide variety of feedstock. Yet, further scale-up is necessary to advance this technique towards commercialization in industry. In this study, a pilot-scale prototype unit (processing capacity of 1 barrel/day) was designed and manufactured based upon the previous achievements, and a bitumen sample recovered from the Steam Assisted Gravity Drainage (SAGD) process was chosen as a typical extra heavy crude for the upgrading. A 30-day upgrading has been conducted smoothly without clogging and a liquid yield of 96.7 % was observed with remarkable enhancements in product quality. The notable decreases in density, viscosity, TAN, asphaltene content, and sulfur content were confirmed and consistent with previous results. A low olefin content implies excellent stability and compatibility of the liquid product. Additionally, a preliminary TEA (Techno-Economic Assessment) and LCA (Life-Cycle Analysis) have been conducted and the beneficial features of this novel technique have been confirmed with higher profitability, lower cost, and lower carbon footprint. This study further consolidates the advantages of this promising technique as a cost-effective and environmentally friendly alternative to hydrotreating for processing extra heavy crudes.

Pd nanocatalyst supported on amine-functionalized mesoporous graphitic carbon nitride (Pd/NH2-mpg-C3N4) was investigated for dehydrogenation of formic acid. The catalyst was analyzed and tested to investigate the effect of amine functionalization on hydrogen generation from formic acid. Pd nanocatalyst was dispersed uniformly on NH2-mpg-C3N4 without agglomeration. The turnover frequency value of Pd/NH2-mpg-C3N4 was 1870 h−1, which was higher than that of Pd/mpg-C3N4 because of the amine functionalization. The Pd/NH2-mpg-C3N4 was also tested to investigate the effect of various reaction conditions (formic acid concentration, sodium formate concentration, and reaction temperature) on hydrogen generation from formic acid. Formic acid concentration negatively affected the catalytic activity, whereas sodium formate concentration positively affected it. Reaction temperature significantly affected the catalytic activity. The apparent activation energy of the Pd/NH2-mpg-C3N4 catalyst was 60.7 kJ mol−1, and a hydrogen generator with the catalyst exhibited high conversion efficiency at an elevated temperature. Consequently, a hydrogen generator with Pd/NH2-mpg-C3N4 is suitable for polymer electrolyte membrane fuel cell systems.

Mordenite-ZSM-22 composite zeolite is prepared by the physical mixing. The structure, pore properties, acid properties and diffusion properties of samples are characterized by the means of XRD, N2 physical adsorption-desorption, SEM, TEM, NH3-TPD, Py-IR, and ZLC. The pore properties and acid properties of mordenite-ZSM-22 composite zeolite can be efficiently modulated by changing mass ratio of mordenite and ZSM-22. In n-C12 hydroisomerization reaction, Pt/HMZ-x displays great capacity in modulate n-dodecane isomers distribution (mono-branched i-C12, multi-branched i-C12, terminal branched i-C12 and central branched i-C12), these results are ascribed to that these composite zeolite catalysts combined the topology structure advantage of mordenite and ZSM-22. When reaction temperature is 280 °C, the ratio of mono-branched i-C12 selectivity to multi-branched i-C12 selectivity (SMB/SMTB) of Pt/HZSM-22, Pt/HMZ-1, Pt/HMZ-3, Pt/HMZ-5 and Pt/HMOR were 37.64, 15.04, 5.48, 5.20 and 1.47, respectively. The ZLC diffusion experiment results indicate that low isomer selectivity of Pt/HMOR is due to its poor diffusivity. On the contrary, Pt/HZSM-22 favors the diffusion of reactants and has better catalytic performance.