BioEnergy Research最新文献

Fatty acid methyl esters (FAMEs) are extensively utilized as pure biofuels due to their renewable origin, biodegradability, and favorable environmental performance. In this study, a wide range of machine learning techniques including Decision Trees, Lasso Regression, AdaBoost, Ensemble Learning, k-Nearest Neighbors (KNN), Convolutional Neural Networks (CNN), Multilayer Perceptron Artificial Neural Networks (MLP-ANN), Random Forest, and Support Vector Regression (SVR) were employed to develop accurate predictive models for FAME density. The models were trained using a comprehensive dataset comprising 2924 experimental density measurements collected from the literature, covering wide ranges of temperature, pressure, molecular weight, and elemental composition. Model performance was rigorously evaluated using statistical metrics such as the coefficient of determination (R²), mean squared error (MSE), and absolute average relative error (AARE%). Among the investigated approaches, the Ensemble Learning model achieved the highest predictive accuracy, yielding an R² of 0.982, a low MSE of 27.75, and an AARE% below 0.14%. Sensitivity analysis and SHAP (SHapley Additive exPlanations) evaluation consistently identified temperature as the dominant factor influencing FAME density, followed by pressure, while molecular weight and elemental composition exhibited comparatively weaker effects. The reliability of the dataset was further confirmed through leverage-based outlier detection. Overall, the proposed data-driven framework provides a cost-effective and reliable alternative to experimental density measurements, enabling accurate density estimation of FAME-based biofuels over broad operating conditions.

Waste gasification is a promising route for sustainable hydrogen production, yet its deployment remains highly uneven across regions. This review critically analyzes the technological, economic, environmental, and socio-political constraints governing waste gasification in industrialized and emerging economies, with particular emphasis on feedstock heterogeneity, cost competitiveness, and governance challenges. Key research gaps are identified, including the limited availability of experimental studies on unsegregated wastes, the underutilization of process intensification strategies such as high-gravity and membrane-assisted gasifiers, and the lack of integrated environmental and social life cycle assessments under real-world conditions. Based on these insights, a regionalized deployment roadmap is proposed, distinguishing large-scale gasification systems with integrated CO₂ capture in China, the United States, and Europe from decentralized, modular, and digitally assisted configurations tailored to Latin America and Africa. Sustainability benefits differ markedly by region, with emission reduction and circularity gains in industrialized economies and improvements in energy access, waste management, and social inclusion in emerging regions. Pilot-scale evidence further indicates that biomass–plastic co-gasification can enhance hydrogen yields by up to 90–110% under optimized conditions.

Sorghum presents promising prospects as an alternative feedstock for bioethanol production, owing to its high sugar content and superior agronomic properties. This study examines the feasibility of sorghum-based bioethanol in supporting the national energy mix target and reducing greenhouse gas emissions. The distribution of areas across 38 provinces in Indonesia related to potential sorghum cultivation was identified using a remote sensing approach, differentiated into four suitability classifications to estimate bioethanol production capacity. The concept of an integrated sorghum processing plant with a capacity of 4 kL per day is adopted, requiring 300 ha of land for cultivation for each bioethanol plant. The results of the study indicate that utilizing the national sorghum potential can significantly contribute to achieving the national biofuel target and reducing greenhouse gas emissions. This study identified 3.334 million ha of land in Indonesia suitable for sorghum cultivation, with a bioethanol production potential of 13.31 million kL per year, equivalent to 36.95% of the national gasoline demand in 2023, the base year of this study. Under the proposed sorghum bioethanol scenario, this alternative fuel could reduce greenhouse gas emissions by up to 25.8 million tons of CO₂eq by 2045 compared to the business-as-usual scenario. The implementation of sorghum-based bioethanol aligns with the national emission reduction program aimed at achieving the net-zero emissions target by 2060. Thus, sorghum can be one of the solutions to support the national energy and environmental targets. This study provides an important foundation for the development of sorghum-based bioethanol in Indonesia.

The quality attributes of briquettes depend on feedstock characteristics and process conditions. This study aimed at optimizing compressive strength and specific energy requirement using Response Surface Methodology (RSM). An RSM based on Central Composite Design (CCD), comprising four factorial, four axial, and six center points, was used to generate different sets of experimental conditions. Each condition was replicated three times, yielding a total of 42 experimental runs. Briquetting temperature (40–110 °C) and compression pressure (34–204 MPa) were treated as independent variables in the response modeling. The model terms included constant, linear, interaction, and quadratic components. The optimum briquetting temperature and pressure were 110 °C and 123 MPa for raw groundnut shells and 97 °C and 108 MPa for raw maize stalks. The corresponding optimum specific energy requirement and compressive strength were 22.5 kJ/kg and 21.4 MPa for groundnut shells, and 11.0 kJ/kg and 42.4 MPa for maize stalks. Torrefaction increased the specific energy requirement for briquetting by 42.2% for groundnut shells and 31.8% for maize stalks. Conversely, torrefaction reduced the compressive strength by 74.8% for groundnut shell briquettes and 18.6% for maize stalk briquettes.

The effect of thermal and electrohydrolysis pretreatment on methane yield from lignocellulosic pulp and paper mill sludge was studied in batch assay at mesophilic (37 ± 2°C) conditions. Both pretreatments showed an enhanced methane production rates and shortened the lag phase, with thermal and electrohydrolysis methods yielding increases of 33.73% and 39.20%, respectively. Electrohydrolysis also demonstrated superior energy recovery, achieving a net energy gain of 12,259 kJ which was 57% higher than the 7,040 kJ obtained from thermal pretreatment. In addition, three kinetic model were evaluated. All the models fit the experimental data with greater R²> 0.970. The modified Gompertz model showed the best fit in both pretreatment with greater R²> 0.998. Improved methane production couples with high net energy gain and reduced retention time could make the electrohydrolysis pretreatment more attractive for future installation of the full-scale industrial anaerobic reactor level.

This study presents the first comprehensive optical characterization of drop-casted Zea mays pigment-protein complex (PPC) films for bio-based optoelectronic applications. Absorbance spectroscopy revealed the retention of strong chlorophyll a and b peaks, essential for efficient light harvesting. Photoluminescence analysis via Voigt fitting showed asymmetric emission with an 8–10 nm red-shifted primary chlorophyll a peak and a secondary far-red peak at 733–743 nm, indicating pigment aggregation and reorganized excitonic states after low-temperature storage. Fourier-transform infrared (FTIR) spectroscopy confirmed preservation of key molecular structures and functional groups, supporting the films’ stability and integrity. Qualitative adhesion and stability tests demonstrated robust film formation with promising durability. These results demonstrate that Zea mays PPC films retain functional photoactivity and structural stability in solid form, advancing their potential use in sustainable bio-optoelectronic materials and devices.

The increasing need for decentralized and sustainable energy sources has fueled interest in biochar, a high-carbon-content material obtained from biomass pyrolysis or gasification, as a viable option for bioelectricity production. Considering its tunable porosity, high carbon content, and natural electrical conductivity, biochar presents an unprecedented platform for transforming biomass waste into useful energy. Biochar to bioelectricity conversion contributes not only to renewable energy targets but also to carbon sequestration and waste valorization. The review presents a bibliometric analysis of biochar to bioelectricity, as well as its applications. The study systematically examines biochar conversion technologies such as pyrolysis, gasification, torrefaction, and their applications in electrical energy systems. Further, it discusses a performance-enhancing modification, techno-economic evaluation, technology readiness level (TRL), future perspectives, and challenges. The present study emphasizes the revolutionary contribution of biochar to a sustainable energy future through the rapid implementation of biochar-driven energy solutions, which significantly support sustainable development goals (SDGs) 7 and 13.

Graphical Abstract

To promote agricultural waste resource utilization and carbon neutrality goals, this study adopted the Life Cycle Assessment (LCA) method to construct a full-chain evaluation model covering “bagasse collection, pyrolysis carbonization, adsorption, soil disposal”, quantitatively analyzing the resource consumption and environmental impacts of each stage. The results indicate that the biochar obtained from processing 1 ton of bagasse achieves a net greenhouse gas emission reduction of 1.2 × 10³ kg CO₂-eq, demonstrating significant carbon-negative potential. Sensitivity analysis indicates that soil carbon sequestration and by-product energy substitution are the main drivers of emission reduction, while Monte Carlo simulation analysis further verified the robustness of the results. Furthermore, the system can effectively reduce acidification potential (–1.5 × 10⁻¹ kg SO₂-eq) and human toxicity potential (–3.95 × 10² kg 1,4-DCB-eq); however, attention must be paid to its negative impacts on photochemical ozone formation (8.2 × 10⁻¹ kg C₂H₄-eq), abiotic resource consumption (1.73 × 10⁻⁴ kg Sb-eq), and eutrophication potential (6.00 × 10⁻² kg PO₄³⁻-eq). The study demonstrates that bagasse-derived biochar production yields net positive environmental benefits, primarily driven by its carbon-negative effect, while also identifying specific impact categories requiring further optimization, thereby providing a scientific basis for advancing sustainable biomass utilization strategies.

Industrial operations and the burning of fossil fuels discharge greenhouse gases (GHGs), including COx, NOx, and SOx. The emission of GHGs has increased by 51% (2021) in comparison to 1990, which is mainly coming from the energy sector (> 75%), followed by agriculture (> 11%), industrial processes (> 6.5%), waste and landfill (6–7%). An algal carbon capture system can sequester COx along with NOx and SOx from the environment to biomass and other valuable products. Algae can be cultivated in open ponds as well as closed reactor systems supplied with CO₂ rich gaseous stream as algal feed. Algae can contribute to biofuel generation via direct metabolisms (fuel is produced directly during growth, e.g., hydrogen) and via fermentation of algal biomass and metabolites. During growth, algae accumulated significant amounts of carbohydrate and lipids, which can be considered as feed for the production of fuels like ethanol, butanol, and biodiesel, and aviation fuels, etc. The approach seems sustainable for capturing inorganic carbon, but economic feasibility is a major obstacle due to tedious biomass recovery, compound extraction, and conversion to fuel. The current review represents the application of algal cultivation for CO₂ mitigation from the environment for the production of biomass and other commercial products.

The production of bioplastics has been extensively investigated in recent decades, with the purpose of reducing the global dependence on fossil resources. In this review, the main routes to produce bioplastics and a critical discussion of these technologies are presented. The synthesis routes to produce biodegradable and non-biodegradable bioplastics are discussed. Additionally, approaches to improve the environmental footprint of some conventional plastics that have no immediate solutions of substitution are also addressed. A comparison of the main properties of the bioplastics considered and a general perspective of the bioplastics market are also provided. Because these themes have often been reviewed separately, this article aims to provide a unified general perspective of bioplastics in the context of a biobased economy, as well as pointing out some of the hurdles in such way.