<?xml version="1.0" encoding="utf-8"?>
    <rss version="2.0">
      <channel xmlns:content="http://purl.org/rss/1.0/modules/content/">
        <title>Frontiers in Fuels | New and Recent Articles</title>
        <link>https://www.frontiersin.org/journals/fuels</link>
        <description>RSS Feed for Frontiers in Fuels | New and Recent Articles</description>
        <language>en-us</language>
        <generator>Frontiers Feed Generator,version:1</generator>
        <pubDate>2026-10-29T05:04:42.846+00:00</pubDate>
        <ttl>60</ttl>
        <item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1954106</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1954106</link>
        <title><![CDATA[Emerging fuel cell technologies: advances in membranes, performance, and energy efficiency]]></title>
        <pubdate>2026-10-27T00:00:00Z</pubdate>
        <category>Review</category>
        <author>José Roberto de Matos Filho</author><author>Layla Mikaely Oliveira Freires</author><author>Lizandra Gadelha Rios</author><author>Silvio Nicholas Cruz de Oliveira</author><author>José Cleiton Sousa dos Santos</author><author>Maria Cristiane Martins de Souza</author>
        <description><![CDATA[Fuel cells convert the chemical energy of a fuel into electricity through separated electrochemical half-reactions. Because they are not heat engines, their efficiency is set by the ratio between the Gibbs free energy and the enthalpy of the cell reaction (ΔG/ΔH ≈ 83% for H2/O2 at 25 °C, higher-heating-value basis) and is not bounded by the Carnot factor of a thermal cycle; this, rather than any exemption from the second law, is the origin of the efficiency advantage of fuel cells, which is pronounced at small scale and part load. Realizing that, in practice, the advantage is limited by the electrolyte. Perfluorosulfonic acid (PFSA) ionomers such as Nafion® remain the benchmark. They are costly to fluorinate, lose conductivity when dehydrated above ∼80 °C or at low relative humidity, are vulnerable to radical-induced degradation and reactant crossover, and belong to the per- and polyfluoroalkyl substances (PFAS) now under regulatory pressure. These four constraints underpin the biopolymer- and nanomaterial-based alternatives examined. This review synthesizes strategies in membrane engineering, catalyst design, and energy conversion efficiency for proton exchange membrane cells and related architectures. Biopolymer membranes derived from chitosan and tamarind seed polysaccharide, combined with crosslinking and hybridization, reach proton conductivities above 0.2 S cm−1 while reducing fuel crossover and improving stability. Functionalized graphene oxide (sulfonation, phosphorylation, and three-dimensional sponge-like architectures) provides continuous, spatially stable ionic channels and acts as a barrier to methanol and hydrogen; the conductivities reported for self-supported graphene oxide films are, however, in-plane values and are not directly comparable with the through-plane conductivity of commercial membranes. Non-noble-metal catalysts and enzymatic bioelectrocatalytic systems, particularly laccase-based oxygen reduction and glucose-oxidizing biofuel cells, eliminate dependence on platinum but remain three to six orders of magnitude below platinum-based systems in power density. Biocatalyst degradation, industrial scalability, experimental reproducibility, and the levelised-cost trade-off between initial material cost and service life remain unresolved. Artificial-intelligence-assisted materials discovery, protein engineering, low-energy routes to graphene oxide, and the expansion of fuel cells into biomedical and portable-electronics niches are likely to convert materials-level gains into deployable technology.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1931909</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1931909</link>
        <title><![CDATA[Sustainable aviation fuels in the United Kingdom: an encouraging start but more to be done]]></title>
        <pubdate>2026-10-21T00:00:00Z</pubdate>
        <category>Perspective</category>
        <author>Duncan McCourt</author>
        <description><![CDATA[Sustainable aviation fuel (SAF) is crucial to decarbonising aviation and will possibly reduce the formation of condensation trails. This article explores the regulatory framework supporting SAF usage and development in the United Kingdom, looking at what more needs to be done in the short and long term to grow the industry and decarbonise aviation at a reasonable cost to consumers. All three generations of SAF are important; their contributions will vary over time. SAF diversifies a proportion of aviation’s energy supply away from globally traded fossil fuels. A domestic SAF industry can support energy security, reducing exposure to price shocks and geopolitical risks, while also supporting thousands of jobs. The United Kingdom has one of the best regulatory frameworks in the world for SAF. The SAF Mandate and other mechanisms incentivise and reward lower carbon intensity. However, the mandated use of SAF alone cannot unlock domestic investment at scale. Alongside such demand-side intervention, it will be necessary to have supply-side intervention. In the United Kingdom, this supply-side support is the Revenue Certainty Mechanism in the 2026 SAF Bill. This provides a legal framework to enable the Department for Transport to offer revenue certainty contracts to SAF producers and raise a levy on fuel suppliers to fund the costs of those contracts. The article advocates that the government should: decarbonise UK aviation in the most cost-effective and sustainable way; ensure aviation has fair access to biomass feedstock to support SAF production; achieve parity between the policy regime for road fuels and SAF; ensure that biomass feedstock provides the greatest lifecycle emission savings; maintain stakeholders’ confidence in the sustainability of SAF; and boost confidence in the investment case for SAF, particularly second-generation SAF made from agricultural, forestry, and municipal waste.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1932327</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1932327</link>
        <title><![CDATA[Target selection of native yeasts isolated from the industrial process: a strategy to optimize bioethanol production]]></title>
        <pubdate>2026-10-16T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Claudia Steckelberg</author>
        <description><![CDATA[The intensification of climate change demands a transition toward renewable energy matrices, positioning bioethanol as a sustainable alternative capable of reducing greenhouse gas (GHG) emissions by up to 90%. Although Brazil’s bioethanol sector is highly consolidated, optimizing alcoholic fermentation remains a challenge, particularly regarding the selection of robust yeast strains. Industrial fermentation typically begins with commercial Saccharomyces cerevisiae inocula, which are frequently outcompeted and replaced by wild, autochthonous strains throughout the harvest season. While some native strains compromise production efficiency, others exhibit superior adaptation to industrial stress. This study presents an industrial case study based on long-term microbiological monitoring (2018–2024) of an operational unit that integrated the native S. cerevisiae strain DBP-701–isolated in 2017 due to its superior fermentative performance–into a starter blend with commercial strains (PE-2, Angel, and CAT-1). Population dynamics revealed that DBP-701 consistently exhibited high prevalence within the microbial consortium, maintaining strong population persistence during the 2021 and 2022 cycles from the beginning to the end of the harvests. This high prevalence was associated with a reduction in the establishment of invasive wild strains under routine factory conditions. However, the 2024 harvest diverged from historical patterns; we hypothesize that extreme weather events, including intense heatwaves and sugarcane fires, contributed to increased metabolic stress and altered raw material quality, coinciding with a disruption in strain persistence. Overall, deploying selected native yeasts like DBP-701 represents a valuable strategy for enhancing population stability under standard operational conditions, while highlighting potential vulnerabilities under severe environmental perturbations.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1891411</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1891411</link>
        <title><![CDATA[Qualification of sustainable aviation fuels: system constraints and opportunities for scale]]></title>
        <pubdate>2026-09-09T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Matthew Jee</author>
        <description><![CDATA[Sustainable aviation fuels (SAF) are widely recognised as a key component of aviation decarbonisation strategies. However, the introduction of new fuels into a safety-critical aviation system requires robust evaluation to ensure compatibility with existing aircraft, engines and fuel infrastructure. This review examines the qualification of synthetic aviation turbine fuels within established qualification and certification frameworks, with a focus on how the ASTM D4054 evaluation process operates in practice and how it interacts with broader factors influencing SAF deployment. The paper analyses how differences in fuel composition, including bulk properties, trace species and performance characteristics, are translated into proportionate evidence requirements through a structured, risk-based approach. It highlights that qualification is not a prescriptive sequence of tests, but a distributed evidence-generation and governance process involving fuel developers, testing organisations, original equipment manufacturers, standards bodies and other stakeholders. As the diversity and maturity of synthetic blend components increases, the performance of the qualification system is shaped not only by intrinsic technical uncertainty, but also by structural factors including testing infrastructure, representative fuel availability, data quality, OEM review capacity and stakeholder coordination. The review distinguishes clearly between fuel qualification and deployment. For several established pathways, qualification has not generally been the primary constraint on SAF uptake; deployment remains strongly influenced by feedstock availability, production scale, economics, infrastructure and policy certainty. However, the complexity, timescales and cost of evaluation can still influence pathway accessibility, particularly for more novel fuels, highlighting the need to improve qualification efficiency without compromising technical integrity or safety assurance. As policy ambition increases and more chemically diverse candidate fuels seek approval, qualification may become a more material constraint on the pace, predictability and diversity of future SAF deployment. Drawing on developments in pre-screening, distributed testing, Clearing House coordination, qualification-readiness assessment, data standardisation and proportionate evaluation approaches, the review shows that the qualification system is evolving to improve efficiency and scalability while maintaining the requirements of safety, operability and long-term system integrity. Overall, the paper positions fuel qualification as an enabling component of the SAF ecosystem whose future scalability will depend on earlier uncertainty reduction, improved data generation, coordinated testing infrastructure and continued expert review.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1873774</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1873774</link>
        <title><![CDATA[Thermogravimetric kinetic analysis of mallow (Urena lobata Linn.) stem residues to evaluate their potential in energy applications]]></title>
        <pubdate>2026-09-03T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Jardson dos Santos Reis</author><author>Maria Fernanda S. Vieira</author><author>Florencia João Macamo</author><author>Jorge A. S. Tenório</author><author>Walter Ricardo Brito</author><author>Luiz Kleber C. De Souza</author>
        <description><![CDATA[The growing demand for renewable energy has increased interest in the use of lignocellulosic residues for energy applications. Mallow (Urena lobata Linn.) stem residue is an underutilized Amazonian byproduct generated after fiber extraction, whose thermal degradation behavior remains poorly explored. This study evaluated the energy-related potential of mallow stem residue through thermogravimetric analysis, TG-MS, isoconversional kinetic modeling, thermodynamic assessment, and reaction mechanism analysis. The biomass was characterized by proximate and lignocellulosic analyses and subjected to non-isothermal thermogravimetric experiments under N2 atmosphere at heating rates of 2.5, 5, 10, 15, and 20 °C min-1. The use of FWO, Kissinger-Akahira-Sunose, Starink, and Vyazovkin methods allowed the consistency of activation energy estimates to be evaluated and enabled the conversion-dependent reactivity of the biomass to be described without assuming a single reaction model. TG/DTG results revealed a multistage degradation process, with the main devolatilization occurring between 200°C and 400 °C. TG-MS indicated the release of H2O, CO2, and light organic fragments, while minor m/z assignments were treated as tentative due to possible fragment overlap. The apparent activation energy decreased with conversion, ranging from approximately 133 to 104 kJ mol-1, with average values between 122.95 and 126.39 kJ mol-1. Thermodynamic parameters indicated a thermally activated and energy-demanding decomposition process, while reaction mechanism analysis suggested changes in the dominant mechanism throughout conversion. Overall, mallow stem residue showed thermal and kinetic characteristics comparable to other lignocellulosic feedstocks, indicating potential for energy-related applications. However, further product characterization, ash composition analysis, and reactor-scale studies are required to confirm its practical applicability in bioenergy conversion systems.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1920446</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1920446</link>
        <title><![CDATA[Recent advances in modelling and experimental studies of SCR catalysts in ammonia-fuelled engine applications]]></title>
        <pubdate>2026-08-26T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Madhumitha Rajendran</author>
        <description><![CDATA[Ammonia (NH3) has emerged as a promising carbon-free fuel for decarbonising internal combustion engines and power systems. However, its combustion produces elevated nitrogen oxide (NOx) emissions and ammonia slip, requiring effective exhaust aftertreatment. Selective catalytic reduction (SCR) is the leading technology for NOx control, but its application to ammonia-fuelled engines presents unique challenges, including NH3-rich exhaust, variable NO2:NOx ratios, low exhaust gas temperatures (EGT), high water-vapour concentrations, and increased potential for nitrous oxide (N2O) formation. This review critically examines recent advances in SCR catalyst development and modelling for ammonia-combustion exhaust treatment. The performance of vanadia-based catalysts, transition metal oxides, and Cu- and Fe-exchanged zeolites (CuZ and FeZ) is evaluated in terms of activity, selectivity, durability, and resistance to deactivation under ammonia-rich conditions. Current understanding of NH3-SCR reaction mechanisms, catalyst ageing, and N2O formation is discussed alongside advances in microkinetic, reactor-scale, and computational fluid dynamics (CFD) modelling. Particular emphasis is placed on the strong coupling between combustion and aftertreatment, arising from the dual role of NH3 as both fuel and reductant, and the need to integrate experimental observations with predictive modelling. Finally, key research priorities are identified, including catalyst development for NH3-rich exhaust, realistic experimental validation, improved prediction of N2O emissions, and integrated combustion–aftertreatment optimisation to enable efficient, low-emission NH3-fuelled power and propulsion systems.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1885872</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1885872</link>
        <title><![CDATA[Investigation of fermentable sugar production through microwave-assisted alkali pretreatment and subsequent acid hydrolysis on Prosopis juliflora biomass]]></title>
        <pubdate>2026-08-18T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Vijayasri Mohandoss</author><author>Prem Kumar Muthhurasu</author><author>Akshaya Gayathri Senthil Kumar</author><author>Thirupathi Kumara Raja Selvaraj</author><author>Varadarajan Gunasekar</author><author>Govindarajan Ramadoss</author>
        <description><![CDATA[This study investigates the potential for producing fermentable sugars from Prosopis juliflora stem biomass using an unique approach using microwave-assisted KOH pretreatment. Various operating parameters in the microwave-assisted KOH pretreatment involves KOH conc (1, 2% and 3%), biomass loading (1, 3 and 5 g), microwave power (150, 300 and 450 W) and irradiation time (3, 4 and 5 min) were optimized by response surface methodology (RSM) using Box-Behnken Design (BBD). Hydrolysis was also optimized using various concentrations of sulphuric acid (1, 3, 5, 7% and 9%) for 60 min at 120 °C to produce fermentable sugars which was compared with the liquid obtained after the pretreatment. The native and the pretreated P. juliflora stem biomass was characterized by scanning electron microscope (SEM). Under the optimized conditions (2% KOH, 5 g biomass loading, 150 W, 4 min, followed by 5% H2SO4 hydrolysis at 121 °C for 60 min), a maximum reducing sugar concentration of 2.25 mg/mL (225 mg g-1 biomass) was achieved. The integrated microwave-assisted alkaline pretreatment significantly enhanced biomass deconstruction and fermentable sugar recovery while employing low chemical concentration and short processing time. These findings demonstrate that P. juliflora stem biomass is a promising lignocellulosic feedstock and that the proposed low-severity, scalable pretreatment strategy has considerable potential for sustainable and economically viable bioethanol production.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1840089</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1840089</link>
        <title><![CDATA[Utilization of Madhuca indica ash as a green catalyst for transesterification of Madhuca indica oil: process optimization and engine analysis]]></title>
        <pubdate>2026-07-03T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>S. Aparna</author><author>S. Rahul</author><author>D. Dhanuprabha</author><author>S. Raaghavi</author><author>A. Arumugam</author>
        <description><![CDATA[This study investigates a heterogeneous catalyst derived from calcined and NaOH-treated Madhuca indica (M. indica) shell ash for the transesterification of M. indica seed oil. Process parameters were optimized using a central composite design (CCD) within response surface methodology (RSM), resulting in a maximum biodiesel yield of 92.3% (GC-MS area-based ester content). The optimal conditions were a methanol:crude oil molar ratio of 22.5:1, a reaction temperature of 70 °C, a catalyst loading of 2.5 wt%, and a reaction time fixed at 6 h. Engine performance was evaluated on a single-cylinder diesel engine operating at 1,500 rpm, utilizing B10 and B20 biodiesel blends. Under full load conditions, B10 reduced hydrocarbon (HC), carbon monoxide (CO), and smoke emissions by 21.43%, 12.78%, and 5.97%, respectively. B20 reduced HC, CO, and smoke emissions by 27.55%, 20.3%, and 12.23%, respectively, relative to diesel. Nitrogen oxides (NOx) emissions increased by 8.37% for B10% and 17.1% for B20 relative to conventional diesel. A techno-economic analysis (TEA) was performed using an Aspen Plus economic analysis process model; results and underlying assumptions are detailed in the TEA section.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1871799</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1871799</link>
        <title><![CDATA[Municipal solid waste gasification with alcohol-to-jet upgrading produces low-carbon aviation fuel at fossil-competitive costs]]></title>
        <pubdate>2026-07-01T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Joseph Amponsah</author><author>Pallavi Dubey</author><author>Jian Shi</author><author>Mark Mba Wright</author>
        <description><![CDATA[IntroductionMunicipal solid waste is an abundant feedstock with established collection infrastructure and negative or near-zero acquisition costs. This study quantifies the techno-economic and environmental performance of a gasification and alcohol-to-jet pathway that converts 2,000 tonnes per day of municipal solid waste into sustainable aviation fuel.MethodsProcess modeling was conducted in BioSTEAM v2.44.3. Techno-economic analysis and life cycle assessment were performed, including Monte Carlo uncertainty analysis incorporating syngas H2/CO variability, catalyst lifetime, MSW moisture, plastic fraction, and financial parameters.ResultsThe process yields 9.3 gallons of fuel per tonne of incoming waste, with aluminum, iron, and propanol recovered as co-products. The minimum fuel-selling price (MFSP) ranges from $1.25 to $3.68 per gallon depending on tipping-fee credits and co-product revenues, with the lower bound within the 2019–2024 petroleum jet fuel range of $2.00–$3.50 per gallon. Cradle-to-gate global warming potential is 33.67 g CO2-eq/MJ, representing a 63% reduction relative to conventional jet fuel. Natural gas and electricity account for 54% of total emissions, while avoided landfill methane and metal recovery provide 5.8 g CO2-eq/MJ in credits. Monte Carlo analysis yields a 90% confidence interval of –$0.12 to $2.61/gal for MFSP and 28.4–42.8 g CO2-eq/MJ for GWP.ImplicationsEconomic performance is most sensitive to internal rate of return and aluminum price, while environmental performance is primarily driven by electricity sourcing and plastic composition. Overall, the pathway demonstrates robust climate benefits and competitive cost potential across uncertainty ranges.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1860328</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1860328</link>
        <title><![CDATA[Inducible two-step cultivation of microalgae: engineering the growth and lipid biosynthesis for biofuel production]]></title>
        <pubdate>2026-06-25T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Krishnakumar Mohan</author><author>Arathi Sreenikethanam</author><author>Subhisha Raj</author><author>Niharika Mondru</author><author>Amit K. Bajhaiya</author>
        <description><![CDATA[Microalgae have significant economic importance due to their fast growth and diverse biomass composition. However, achieving cost-effective large-scale production while maintaining the high yields of the desired metabolite remains a major challenge. Conventional cultivation strategies face an inherent trade-off: conditions that promote microalgae development often suppress metabolite synthesis, whereas stress conditions that induce the desired metabolite synthesis inhibit growth and overall biomass production. In recent years, there has been increasing interest in a two-step cultivation, in which microalgae are first grown under optimal conditions for maximal biomass, followed by exposure to stress to trigger targeted metabolite synthesis. Despite its advantages, this approach also faces limitations in precisely controlling metabolite induction and in avoiding undesirable stress responses. To overcome this issue, integrating inducible genetic switches in the second cultivation phase, particularly stress-responsive promoters linked to the gene of interest, offers a promising strategy to enhance metabolite production in a controlled manner. However, until now, there are no published studies on the utilization of inducible promoters along with a two-stage cultivation system for microalgae. The inducible systems are activated by specific stress factors or substrates, enabling targeted activation of desired pathways while limiting off-target effects. This review provides an overview of the mechanistic framework of the two-step cultivation system, types and mechanisms of inducible promoters, and switch-based metabolic regulation in microalgae. Finally, we will highlight the challenges and opportunities for integrating synthetic biology tools with cultivation engineering to enhance and sustain targeted metabolite production in microalgal biorefineries.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1825931</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1825931</link>
        <title><![CDATA[Laminar flame speeds of dimethyl ether-propane/butane/propylene air mixtures]]></title>
        <pubdate>2026-06-23T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Jordan Walsh</author><author>Dezheng Li</author><author>Yanming Chen</author><author>Yang Zhang</author><author>Ruoyang Yuan</author>
        <description><![CDATA[IntroductionDimethyl ether (DME) has potential to be used both blended with or as an alternative to Liquefied Petroleum Gas (LPG) to reduce the carbon emissions of a fuel used globally for cooking and heating. Standards to enable the adoption of this require flame speed measurements of the blends of these fuels.MethodsMeasurements of counterflow premixed flame speeds for blends of DME, propane, butane, and propylene at fuel-air equivalence ratios (φ) from 0.75 to 1.6 have been made. These measurements were taken to fill a gap in the current published datasets that primarily have focussed on pure fuels and blends of LPGs constituent gases. These measurements have been produced through a mixture of empirical and simulation work.ResultsWe found the flame speeds of the blends overall increase from 0.25 m/s at φ = 0.75 to between 0.4 m/s and 0.45 m/s at φ = 1.0 peaking around φ = 1.0 to 1.1 before decreasing as φ increases further.DiscussionThese data will be useful to support the production of industrial standards that allow for greater adoption of renewable DME as an alternative low carbon fuel to fossil LPG.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1756561</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1756561</link>
        <title><![CDATA[Pilot scale demonstration of potential for decarbonisation of industrial heating processes using hydrogen cofiring]]></title>
        <pubdate>2026-06-01T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Andrew D. Heeley</author><author>Karen N. N. Finney</author><author>János Szuhánszki</author><author>Abdulaziz Gheit</author><author>Jee Loong Hee</author><author>Mohamed Pourkashanian</author>
        <description><![CDATA[This paper aims to evaluate whether cofiring hydrogen and natural gas mixtures are suitable as industrial furnace fuels and to identify further characteristics that need more detailed understanding to enable successful implementation of fuel switching. The outcome of this research and further investigations will ensure that the full capability of fuel switching becomes available to energy-intensive process operators. Co-firing natural gas and hydrogen leading to dedicated hydrogen combustion are pathways to decarbonise industrial processes and can enable future hydrogen utilisation and interoperability with fossil fuels. The key observations from pilot-scale industrial furnace trials at the University of Sheffield Energy Innovation Centre included: (1) Radiant heat flux depended primarily upon furnace temperature with no relationship measured with varying fuel composition. (2) The chamber geometry, radiant heat flux from solid surfaces and control temperature achieved were more significant to the furnace heat exchange than the fuel mixture. (3) Firing with natural gas and hydrogen mixtures did not affect furnace temperature or uniformity beyond variations attributable to other process conditions. (4) Gas temperatures and species were distributed uniformly within the fully mixed atmosphere, which represented 2/3 of the chamber volume. (5) Gas temperature and species distributions were not affected by fuel composition, therefore measurements from the centre of the chamber were representative of the mean conditions in the fully mixed atmosphere. (6) CFD modelling of the gas and temperature distributions within the furnace enabled thermodynamic and fluid dynamic characteristics to be understood and afforded confidence in experimental and model outcomes. Co-firing hydrogen with natural gas and dedicated hydrogen firing as an interoperable fuel to substitute for natural gas could be a key means to decarbonise hard to abate foundation industries, whilst making continued use of existing capital assets. This investigation demonstrated that understanding hydrogen firing and co-firing will enable the mitigation of perceived risks arising from decarbonisation of energy-intensive industries with low and zero carbon fuels.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1805792</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1805792</link>
        <title><![CDATA[Bioethanol and biobutanol production using algal biomass: pathways and industrial applications]]></title>
        <pubdate>2026-05-22T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Ruchi Pathania</author><author>Pallavi Saxena</author><author>Subhasini Sahoo</author><author>Anupam Kundu</author>
        <description><![CDATA[The increase in global demand for sustainable and eco-friendly energy has intensified research on biofuels derived from renewable biomass. Among various feedstocks, algal biomass has attracted more attention due to its high photosynthetic efficiency, rapid growth rate, and ability to grow on non-arable land using saline or wastewater, thus avoiding competition with food crops. Bioethanol and biobutanol, in particular, have emerged as promising alternatives to fossil fuels because of their cleaner combustion, higher energy content, and compatibility with existing fuel infrastructure. This review provides a comprehensive overview of converting algal carbohydrates into fermentable sugars and then fermentation using microbial or genetically engineered organisms for bioethanol and biobutanol production. Various pretreatment and hydrolysis methods, including mechanical disruption, chemical treatments, thermal and biological processes, are discussed for their effectiveness in breaking down the complex algal cell walls and releasing fermentable sugars. Bioethanol is mainly synthesized through the glycolytic pathway and subsequent alcoholic fermentation, whereas biobutanol is produced through the Acetone-Butanol-Ethanol fermentation process. The review also discusses a comparative analysis of algal bioethanol and biobutanol in terms of their industrial applications and market potential. It addresses key challenges, including feedstock availability, process scalability, and production costs, while evaluating opportunities for integration within biorefinery frameworks to enhance overall economic feasibility. Overall, algal biomass represents a sustainable, versatile, and scalable resource for bioethanol and biobutanol production, offering significant potential to support the global transition toward renewable energy. Advancements in research, technological optimization, and supportive policy frameworks will be essential for utilizing the full industrial potential of algal-based biofuels.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1831924</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1831924</link>
        <title><![CDATA[Cyclic acetals as next-generation oxygenated diesel additives from lignocellulosic biomass and plastic waste]]></title>
        <pubdate>2026-05-22T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Anh Ngoc Dao</author><author>Malinee Sriariyanun</author><author>Punyanuch Kunmanee</author><author>Atthasit Tawai</author><author>Suksun Amornraksa</author>
        <description><![CDATA[The decarbonization of heavy-duty transport, marine shipping, and aviation require sustainable liquid fuels that are compatible with existing infrastructure and derived from renewable carbon sources without competing with food or land resources. Cyclic acetals, particularly 1,3-dioxolane and 1,3-dioxane derivatives, have recently emerged as promising oxygenated fuel candidates capable of integrating multiple bio-hybrid carbon streams. These compounds can be synthesized from lignocellulose biomass-derived diols and higher aldehydes, captured CO2 valorized with green hydrogen, and C1 intermediates obtained from plastic waste. Compared with traditional formaldehyde-based routes, the use of higher aldehydes and catalytic CO2/H2 conversion pathways helps overcome thermodynamic limitations and phase-separation challenges in acetal synthesis. Process intensification strategies, such as reactive extraction and reactive distillation in integrated catalytic columns, further enable simultaneous synthesis and purification, simplifying process design and improving scalability. Cyclic acetals exhibit favorable fuel properties, including full miscibility with conventional diesel and jet fuels, high cetane numbers, excellent cold-flow characteristics, and stable oxygenated structures resistant to corrosion and degradation during storage and combustion. These attributes make them attractive molecular platforms for advanced bio-hybrid fuels, enabling pathways toward carbon-neutral and potentially carbon-negative diesel and aviation fuels derived from biomass, CO2, and recycled plastics. Remaining challenges include catalyst durability, impurity tolerance, pilot-scale validation, and techno-economic feasibility.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2026.1748966</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2026.1748966</link>
        <title><![CDATA[The role of combustion (and fuels) in a decarbonizing world]]></title>
        <pubdate>2026-03-02T00:00:00Z</pubdate>
        <category>Review</category>
        <author>Jörg Leicher</author><author>Anne Giese</author><author>Christoph Wieland</author>
        <description><![CDATA[Access to energy is essential for the modern world, yet at the same time, anthropogenic greenhouse gas emissions are caused by energy-related activities across all sectors due to the predominance of fossil fuels. Today, most of the primary energy is still being provided by fossil fuels, with combustion being a key technology. In order to combat climate change, energy has to be decoupled from greenhouse gas emissions, with electricity and electrification being important pathways towards a net-zero energy system. However, electricity also has drawbacks as an energy carrier, especially in the context of large-scale energy storage, but also for applications requiring high energy densities. This, in addition to providing dispatchable power generation capacities for grid balancing and covering longer periods of reduced renewable power generation, is expected to result in significant contributions of synthetic and biogenic fuels to the energy landscape. The main purpose of combustion-based technologies will change from providing most of the primary energy to the energy system to complementing variable renewable energies when and where needed. This change of purpose has consequences for the directions of combustion research and development: while traditional topics such as equipment efficiency and pollutant emissions such as NOX will still be important, other topics such as more flexible and dynamic operation modes, hybrid applications and system integration will play a much bigger role in the future, along with the use of new fuels such as hydrogen or ammonia.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2025.1670642</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2025.1670642</link>
        <title><![CDATA[Brown algae-functionalized clays as a novel biosupports for lead-free bismuth halide perovskites in the CO2 reduction]]></title>
        <pubdate>2026-01-16T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Emireth A. Mellado-Lira</author><author>Edith Luévano-Hipólito</author><author>Luis F. Garay-Rodríguez</author><author>Leticia M. Torres-Martínez</author>
        <description><![CDATA[IntroductionOne of the main environmental problems is air pollution due to high CO2 emissions, a greenhouse gas that contributes to climate change because of the excessive use of fossil fuels. For this reason, CO2 reduction emerges as a promising solution by converting it into renewable fuels using sunlight and advanced semiconductor materials. Recently, hybrid systems based on artificial leaves composed of lead-free halide perovskites and porous support materials have been demonstrated to be highly efficient for CO2 reduction. In addition, the recycling and utilization of natural sources such as the brown algae, considered a plague in the Caribbean, represents an additional advantage for the pollution reduction, carbon sequestration, and social and economic impacts.MethodsThis research proposes an innovative solution to address this environmental problem by demonstrating that hybrid systems based on bismuth halide perovskites (K3Bi2I9) and brown algae-functionalized clay biosupports are promising for the reduction of CO2 with high efficiencies for formic acid production (2.5 mmol h-1) under visible light. The content of the brown algae was investigated to find the best load that promotes higher and stable CO2 reduction efficiencies.ResultsThe presence of the brown algae enhanced light absorption by its chlorophyll, provided free electrons to the semiconductor and highly reactive species (•OH), that favored the formation of C1-C3 products, e.g., HCOOH, CH3COOH, and CH3(CH2)2OH, with efficiencies in the order of >1 mmol. In addition, the stability of the hybrid systems was demonstrated after five hours of continuous visible light irradiation in liquid phase, which analysis of the medium showed a minimal leaching of potassium.DiscussionThe addition of 5 wt.% brown algae in the clays promoted both high efficiency and stability of the hybrid system by preventing cracking, while promoting a porous framework that maintained effective CO2 adsorption. This enhanced effect was attributed to efficient perovskite encapsulation and the presence of chlorophyll (from algae) acting as an electron donor, enhancing light absorption and charge transfer. This synergistic effect enabled efficient CO2 conversions to C1–C3 value-added products. In conclusion, this work demonstrated that the utilization of abundant natural materials such as clays and sargassum supports an ecological and scalable approach while addressing global and local environmental problems.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2025.1716359</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2025.1716359</link>
        <title><![CDATA[Tailored porosity from waste biomass: mesoporous bio-adsorbents for targeted treatment of complex industrial wastewaters]]></title>
        <pubdate>2026-01-14T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Saqib Sohail Toor</author><author>Kamaldeep Sharma</author><author>Rebekka Klemmt</author><author>Mohammad Aref Hasen Mamakhel</author><author>Abdenour Achour</author>
        <description><![CDATA[The valorization of waste biomass into tailored adsorbents presents a sustainable strategy for combating industrial water pollution. This study highlights the critical role of precursor morphology in determining the textural properties and function of bio-adsorbents derived from wheat straw (WS) and the organic fraction of municipal solid waste known as biopulp (BP). Through carbonization and KOH activation, the fibrous WS was transformed into a microporous, high-surface-area activated wheat straw (AWS) bio-adsorbent, while the compact BP yielded a mesoporous network in activated biopulp (ABP). This structural difference affects adsorption performance: AWS demonstrated superior efficacy in batch removal of phenols (93.2%) and total organic carbon (85%) from the complex hydrothermal liquefaction aqueous phase (HTL-AP), whereas ABP excelled in treating produced water (PW), achieving >95% removal of organic pollutants. Continuous fixed-bed column studies confirmed the scalability of AWS for HTL-AP treatment, revealing distinct breakthrough dynamics between bulk parameters and specific contaminants. This work provides evidence supporting precursor-dependent tailoring of pore structure for targeted wastewater treatment, providing a possibility for a circular and sustainable solution for the treatment of complex industrial wastewaters.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2025.1722932</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2025.1722932</link>
        <title><![CDATA[Composition-centered prediction of kenaf core saccharification for next-generation bioethanol via machine learning]]></title>
        <pubdate>2025-11-21T00:00:00Z</pubdate>
        <category>Original Research</category>
        <author>Yitong Niu</author><author>Ying Ying Tye</author><author>Chee Keong Lee</author><author>Mardiana Idayu Ahmad</author><author>Cheu Peng Leh</author>
        <description><![CDATA[IntroductionBiomass pretreatment outcomes are heterogeneous across routes and severities, and condition-centered empirical models often fail to generalize beyond the settings on which they were trained, limiting early-stage decisions about where to focus costly wet-lab effort. This study evaluates a composition-centered surrogate that treats the post-pretreatment solid composition—cellulose, hemicellulose, lignin—as the input space and predicts enzymatic glucose yield as the response for kenaf core.MethodsKenaf core solids subjected to water, dilute-acid, and alkaline pretreatments were characterized for post-pretreatment cellulose, hemicellulose, and lignin contents and hydrolyzed under a fixed enzymatic protocol to obtain glucose yield at 24 h. The curated dataset (n = 35) was used to train Random-Forest regressors tuned by six hyperparameter optimizers (grid search, random search, Bayesian optimization, genetic algorithm, particle swarm optimization, and simulated annealing). Generalization performance was assessed using nested cross-validation and a held-out test split, with feature contributions examined via permutation importance and accumulated local effects.ResultsAcross optimizers, held-out performance clustered tightly (test R2 ≈ 0.49–0.55; RMSE 4.42–4.69 GY%), indicating that attainable accuracy is governed more by model capacity and data coverage than by optimizer choice. Feature diagnostics converged on a cellulose-led mechanism, with cellulose showing a positive monotonic effect on yield, lignin a negative effect, and hemicellulose a weaker, context-dependent influence. Iso-yield maps in the cellulose–lignin plane delineated feasible composition windows that prioritize high-cellulose/low-lignin regions under different hemicellulose levels.DiscussionWithin this accuracy band, the composition-centered surrogate is best suited for uncertainty-aware screening to prune unproductive regions of composition space before targeted design-of-experiments, rather than replacing detailed process optimization. The workflow provides a transferable template for small-sample, composition-based modeling of lignocellulosic feedstocks and can be extended to other varieties and integrated with mechanistic descriptors as data accumulate.]]></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2025.1674030</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2025.1674030</link>
        <title><![CDATA[Italy’s biomethane investment under the national recovery and resilience plan: a flagship initiative for Europe’s sustainable fuel transition]]></title>
        <pubdate>2025-10-15T00:00:00Z</pubdate>
        <category>Opinion</category>
        <author>Giorgio Centurelli</author>
        <description></description>
      </item><item>
        <guid isPermaLink="true">https://www.frontiersin.org/articles/10.3389/ffuel.2025.1643675</guid>
        <link>https://www.frontiersin.org/articles/10.3389/ffuel.2025.1643675</link>
        <title><![CDATA[Microalgae: Promising solutions paving the way toward a greener and more sustainable future]]></title>
        <pubdate>2025-08-18T00:00:00Z</pubdate>
        <category>Mini Review</category>
        <author>Yunhan Qin</author><author>Tingfu Li</author><author>Changliang Nie</author><author>Xueyun Geng</author><author>Xiaomin Sun</author>
        <description><![CDATA[Microalgae represent a promising solution for achieving greener and more sustainable applications, owing to their rapid growth rates, high photosynthetic efficiency, and capacity to produce valuable compounds such as lipids. Biofuels based on microalgae have emerged as a promising alternative to fossil fuels due to their sustainable and renewable nature. Moreover, the use of microalgae cultivated in wastewater not only contributes to biofuel production but also provides additional benefits such as wastewater treatment and CO2 sequestration to realize the carbon neutrality. However, the commercial viability of microalgae-based biofuels remains uncertain. This article reviews advancements in microalgae-based sustainable production while exploring its multi-objective applications beyond energy generation. Multi-objective applications, including multi-algal systems, species development, process optimization, and dust suppressant are necessary to improve cost-effectiveness and enhance overall feasibility.]]></description>
      </item>
      </channel>
    </rss>