Future Fuels Research Articles

A kinetic modeling study on octane rating and fuel sensitivity in advanced compression ignition engines

With the development of advanced compression ignition (ACI) engines such as the homogeneous charge compression ignition (HCCI) and the reactivity controlled compression ignition (RCCI), the long existing research and motor octane rating for fuels, i.e., RON and MON, might be insufficient to describe fuel reactivity and performance with these new combustion strategies due to their distinctive engine operating conditions. It is also noted that with stringent regulation of CO2 emissions, a detailed knowledge of fuel reactivity is urgently needed for the selection of novel alternative bio-fuels for transportation, and optimization of their engine performance in the future. It is therefore very important to understand the general fuel properties such as reactivity and sensitivity under different ACI operating conditions. In this modeling study, using validated kinetic mechanisms for ignition, different classes of fuels including hydrogen, alkanes (straight and branched) and alcohols have been simulated under typical HCCI engine conditions using detailed chemical kinetics. The crank angle corresponding to 50% total heat release (CA50) was utilized as an indicator of the fuel reactivity, and iso-contours of CA50 were then plotted in engine operating parameter coordinates, such as the intake temperature, and pressure. It is shown that fuels with the same RON/MON could even exhibit both qualitatively and quantitatively different CA50 iso-contours in specific operating regimes, implying the insufficiency of RON/MON as comprehensive metrics of fuel reactivity in ACI strategies. In addition, operating regimes with high and low sensitivity, as well as potential non-monotonic change in fuel reactivity have been identified by the CA50 iso-contour map for all fuels studied. It is also shown that the combustion phasing can increase, decrease, or exhibit non-monotonic changes with equivalence ratio variation, subject to fuel and operating conditions. This study provides useful insights into the control of ACI combustion phasing and the understanding of SI end-gas auto-ignition, as well as implications on the selection of future alternative fuels and the derivation of fuel surrogate models.

Stabilization of diesel–biodiesel–ethanol (DBE) blends: formulation of an additive from renewable sources

Sustainable policies led to partially replace fossil diesel fuel by biodiesel. However, other technologies, such as diesel–biodiesel–ethanol (DBE) blends, are being investigated. The major challenge related to these mixtures is the improvement in the miscibility and the stability of alcohol in diesel fuel. The stabilization effect of ternary additives, composed of biodiesel and vegetal oil from two renewable sources (soybean and castor oil) and n-butanol obtained through Doehlert designs of experiments, was assessed. This article initially investigated blends with commercial Brazilian diesel S10 fuel with 7 vol% of biodiesel, B7, and hydrous ethanol. However, adequacy to potential future fuels was investigated for Brazilian diesel S10 fuel with up to 30 vol% of biodiesel and anhydrous ethanol. The best additive was defined as a mixture of 72.5 vol% of castor oil, 17.5 vol% of soybean biodiesel and 10 vol% of n-butanol in diesel B15 fuel. Diversity on the carbon chain length and moieties in the additive was required to improve the miscibility of ethanol in diesel fuel. Nevertheless, high content of n-butanol did not contribute to stabilization since it acted as an extraction solvent. The results also showed that a minimum addition of 1.0 vol% was required to have a sufficient short-term and long-term stability in diesel B15 blends at temperatures higher than 10 °C and anhydrous ethanol content up to 20 vol%. Using such blends, the displacement of fossil fuel demand by biofuels can be increased from 7 to 33 vol%.

Debunking Ecofundamentalism

Abstract Rögnvaldur Hannesson, an international authority on natural resource management, has written a well-argued book against ecofundamentalism, which, for him, puts nature before man. He cogently discusses the problems of applying notions of sustainability and biodiversity to the human condition and suggests that in the foreseeable future fossil fuels should still be utilized as energy sources. Hannesson regards models of global warming as scientific but as too uncertain for mankind to radically alter its ways of life. But he does not distinguish clearly between reasonable environmentalists and the real ecofundamentalists who disguise conflicts between themselves and others as conflicts between man and nature.

The attitudes of UK tourists to the use of biofuels in civil aviation: An exploratory study

Tourism generates substantial carbon footprint with its air transport sector holding the largest share. Biofuel technology has been repeatedly trialled in aviation to minimise this carbon footprint. While biofuels can become mainstream aviation fuels in the near future, little is known about public knowledge on and perception of its use within the air transport sector. This signifies considerable knowledge gap as the level of public awareness of a new technology determines the speed of its societal acceptance and may affect its market success. This study explores the attitudes of UK tourists to the use of biofuels in aviation. It finds that while the public are generally aware of biofuel technology, public knowledge of its specific application in aviation alongside the carbon benefits this brings is limited. Future policy-making and managerial measures should aim at enhancing public understanding of biofuel technology use in aviation in the UK.

Impact of the Future Fuel Economy Targets on Powertrain, Driveline and Vehicle NVH Development

Impact of the Future Fuel Economy Targets on Powertrain, Driveline and Vehicle NVH Development

Carbon nitride frameworks padded with graphene as efficient metal-free catalyst for HER in acidic and alkali electrolytes

Although hydrogen evolution reaction (HER) is one of the most promising pathways to generate hydrogen in large-scale for future fuels, it is still lacking efficient and low-cost electrocatalysts. Here, carbon nitride frameworks padded with graphene (CNF-G) are explored as efficient metal-free catalysts with low-cost and good durability via a directly annealing commercial melamine sponge with graphene oxide. Owing to the high electrical conductivity of graphene, CNF-G exhibits outstanding catalytic activity during HER process in wide pH ranges. The overpotentials and Tafel slopes of CNF-G were 149 mV and 116 mV dec−1 in 0.5 M H2SO4, as well as 319 mV and 160 mV dec−1 in 1 M KOH, respectively. More importantly, CNF-G shows a high and stable catalytic activity demonstrated by a multiple cyclic voltammetry and long potentiostatic polarization.

Cover Picture: Advanced Biofuels and Beyond: Chemistry Solutions for Propulsion and Production (Angew. Chem. Int. Ed. 20/2017)

Following the “Fuel Design Process” To arrive at molecular structures with promising qualities for advanced future fuels, the quest for efficient catalytic production pathways based on sustainable feedstocks has to be combined with a detailed knowledge of engine combustion and emission performance. Proceeding towards this goal in “reverse” mode from tailored fuel target molecules to promising production processes is exemplified in a Review by W. Leitner, J. Klankermayer, K. Kohse-Höinghaus et al. on page 5412 ff. for selected routes from biomass to biofuels. Following the “Fuel Design Process” To arrive at molecular structures with promising qualities for advanced future fuels, the quest for efficient catalytic production pathways based on sustainable feedstocks has to be combined with a detailed knowledge of engine combustion and emission performance. Proceeding towards this goal in “reverse” mode from tailored fuel target molecules to promising production processes is exemplified in a Review by W. Leitner, J. Klankermayer, K. Kohse-Höinghaus et al. on page 5412 ff. for selected routes from biomass to biofuels. Aqueous Supercapacitors Metal–Organic Frameworks Heterogeneous Catalysis

Investigation of the effects of biodiesel aging on the degradation of common rail fuel injection systems

Subject of this study is the parametric investigation of the effect of biodiesel aging on the formation of deposits inside common rail Fuel Injection Equipment (FIE). The parameters investigated are key fuel properties and their degradation rate, FAME composition as well as FIE component design. Fuel degradation and deposit formation is simulated in a prototype FIE test rig. A market study was initially performed to monitor market diesel fuel quality in Europe. The sensitivity of the FIE to FAME concentration was investigated with market B7 and B20 test fuel. B20 pre-aging and fuel enhancement with anti-oxidant were studied to assess the impact of fuel degradation speed and level relatively to deposit formation. A selection of EU market B7 fuels with different fresh fuel properties and FAME composition, were comparatively evaluated on the rig as regards their impact on injection flow and pump response deterioration together with their tendency to form deposits. Test rig operation with 2 different injector designs was utilized to further investigate deposit sensitivity. Injection flow deterioration and internal deposits were affected by injector design and fuel aging speed and were found to be related to Total Acid Number. A correlation between initial B7 Rancimat IP and FIE failure due to fuel aging was identified. The methodology developed is proposed as reference test for the evaluation of current and future automotive fuels as regards their tendency to form deposits.

An overview of the effects of fuel molecular structure on the combustion and emissions characteristics of compression ignition engines

Future fuels for compression ignition engines will be required both to reduce the anthropogenic carbon dioxide emissions from fossil sources and to contribute to the reductions in the exhaust levels of pollutants, such as nitrogen oxides and particulate matter. Via various processes of biological, chemical and physical conversion, feedstocks such as lignocellulosic biomass and photosynthetic micro-organisms will yield a wide variety of potential fuel molecules. Furthermore, modification of the production processes may allow the targeted manufacture of fuels of specific molecular structure. This paper therefore presents an overview of the effects of fuel molecular structure on the combustion and emissions characteristics of compression ignition engines, highlighting in particular the submolecular features common to a variety of potential fuels. An increase in the straight-chain length of the alkyl moiety reduces the duration of ignition delay, and the introduction of double bonds or branching to an alkyl moiety both increase ignition delay. The movement of a double bond towards the centre of an alkyl chain, or the addition of oxygen to a molecule, can both increase and decrease the duration of ignition delay dependent on the overall fuel structure. Nitrogen oxide emissions are primarily influenced by the duration of fuel ignition delay, but in the case of hydrogen and methane pilot-ignited premixed combustion arise only at flame temperatures sufficiently high for thermal production. An increase in aromatic ring number and physical properties such as the fuel boiling point increase particulate matter emissions at constant combustion phasing.

Cellulose Elementary Fibrils Assemble into Helical Bundles in S1 Layer of Spruce Tracheid Wall.

The ultrastructural organization of cellulose elementary fibrils (EFs) in wood cell wall is considered to be the prime factor regulating the material characteristics of wood in micro to macro levels and the conversion of delignified wood fibers into various products. Specifically, the complex assembly of EFs in wood cell wall limits its swellability, solubility, and reactivity, for example, in dissolution of cellulose for regeneration of textile fibers, fibril separation for the manufacture of nanocellulose, and enzymatic hydrolysis of cellulose into sugars for their subsequent fermentation to various products, like ethanol for future fossil fuels replacement. Here cryo-transmission electron tomography was applied on ultrathin spruce wood sections to reveal the EF assembly in S1 layer of the native cell wall. The resolution of these tomograms was then further enhanced by computational means. For the first time, cellulose in the intact cell wall was visualized to be assembled into helical bundles of several EFs, a structural feature that must have a significant impact on the swelling, accessibility, and solubility of woody biomass for its conversion into the aforementioned value added products.

Artificial photosynthesis: closing remarks.

This paper derives from my closing remarks lecture at the 198th Faraday Discussion meeting on Artificial Photosynthesis, Kyoto, Japan, February 28-March 2. The meeting had sessions on biological approaches and fundamental processes, molecular catalysts, inorganic assembly catalysts, and integration of systems for demonstrating realistic devices. The field has had much progress since the previous Faraday Discussion on Artificial Photosynthesis in Edinburgh, UK, in 2011. This paper is a personal account of recent discussions and developments in the field, as reflected in and discussed during the meeting. First it discusses the general directions of artificial photosynthesis and some considerations for a future solar fuels technology. Then it comments on some scientific directions in the area of the meeting.

高知県における木質バイオマス発電の現状と課題

高知県における木質バイオマス発電の現状と課題

PERFORMANCE EVALUATION OF FOUR-STROKE SI (SPARK IGNITION) ENGINE USING ETHANOL-GASOLINE BLEND E50 AT VARIABLE LOAD AND COMPRESSION RATIO

Due to combination of factors, such as environmental concerns, high oil prices and the potential for peak oil, development of cleaner alternative fuels and advanced power systems for vehicles has become a high priority for many governments and vehicle manufacturers around the world. Use of Gasoline as an alternative fuel in Gasoline engine is becoming a need, looking at the scarcity of petroleum fuels in near future. This paper investigates the influence of compression ratio and ethanol-gasoline blending to find the effects on four-stroke SI engine performance. In this research, air cooled engine having compression ratio of 9.1 & 9.7 is used. Fuel blend E50 is used in the study and engine operated at a speed range of 600-1100 rpm. Maximum power was obtained for E50 fuel at a compression ratio of 9.1, while, a minimum fuel consumption rate was obtained at a compression ratio of 9.7. This clearly depicts that as compression ratio increases, fuel consumption rate decreases considerably. Further, experimental results showed that comparing several blends, 50% ethanol is cost and power effective for the four-stroke SI engine.

Original Experimental Approach for Assessing Transport Fuel Stability.

The study of fuel oxidation stability is an important issue for the development of future fuels. Diesel and kerosene fuel systems have undergone several technological changes to fulfill environmental and economic requirements. These developments have resulted in increasingly severe operating conditions whose suitability for conventional and alternative fuels needs to be addressed. For example, fatty acid methyl esters (FAMEs) introduced as biodiesel are more prone to oxidation and may lead to deposit formation. Although several methods exist to evaluate fuel stability (induction period, peroxides, acids, and insolubles), no technique allows one to monitor the real-time oxidation mechanism and to measure the formation of oxidation intermediates that may lead to deposit formation. In this article, we developed an advanced oxidation procedure (AOP) based on two existing reactors. This procedure allows the simulation of different oxidation conditions and the monitoring of the oxidation progress by the means of macroscopic parameters, such as total acid number (TAN) and advanced analytical methods like gas chromatography coupled to mass spectrometry (GC-MS) and Fourier Transform Infrared - Attenuated Total Reflection (FTIR-ATR). We successfully applied AOP to gain an in-depth understanding of the oxidation kinetics of a model molecule (methyl oleate) and commercial diesel and biodiesel fuels. These developments represent a key strategy for fuel quality monitoring during logistics and on-board utilization.

Original Experimental Approach for Assessing Transport Fuel Stability

The study of fuel oxidation stability is an important issue for the development of future fuels. Diesel and kerosene fuel systems have undergone several technological changes to fulfill environmental and economic requirements. These developments have resulted in increasingly severe operating conditions whose suitability for conventional and alternative fuels needs to be addressed. For example, fatty acid methyl esters (FAMEs) introduced as biodiesel are more prone to oxidation and may lead to deposit formation. Although several methods exist to evaluate fuel stability (induction period, peroxides, acids, and insolubles), no technique allows one to monitor the real-time oxidation mechanism and to measure the formation of oxidation intermediates that may lead to deposit formation. In this article, we developed an advanced oxidation procedure (AOP) based on two existing reactors. This procedure allows the simulation of different oxidation conditions and the monitoring of the oxidation progress by the means of macroscopic parameters, such as total acid number (TAN) and advanced analytical methods like gas chromatography coupled to mass spectrometry (GC-MS) and Fourier Transform Infrared - Attenuated Total Reflection (FTIR-ATR). We successfully applied AOP to gain an in-depth understanding of the oxidation kinetics of a model molecule (methyl oleate) and commercial diesel and biodiesel fuels. These developments represent a key strategy for fuel quality monitoring during logistics and on-board utilization.

Book Review: Biofuels from Algae: A Promising Future Fuel

Book Review: Biofuels from Algae: A Promising Future Fuel

Involving service users in training in the management of aggression

Involving service users in the education of current & future mental health practitioners is seen as important. It provides the opportunity for developing greater awareness and understanding through the unique insights of people’s lived experience of mental health conditions and of their contact with mental health services. The growing understanding of the contribution this makes to the improvement of services and in developing the mental health practitioners of the future fuels the increase in its practice. In particular, the pre-registration training of mental health professionals such as: social workers, nurses and psychologists. This workshop describes the involvement of service user trainers in the development and delivery of a short training course on physical restraint for mental health practitioners. It considers the impact of including service users who themselves have experience of being restrained in acute mental health settings, from the perspective of course participants, tutors and the service user trainers themselves. A key element of this involvement is the creation of a forum where service users’ contributions are intently listened to and valued by practitioners. Both parties put heads together to critically analyse the good and bad experiences of restraint practices and, the lessons learnt are powerful as evidenced in course participants’ feedback: “Service user involvement makes it real. I appreciate this very much”. “Service user involvement is very relevant and thought provoking – a good way to see how our work affects/impacts patients” In sharing this experience, it is hoped that the physical restraint trainers who are considering involving service users would feel reassured, and that those yet to do so would be encouraged to try.

Layered Perovskite Electrodes with High Performance and Durability for Solid Oxide Electrolysis

In recently years, there has been a robust attention in clean and renewable energy sources due to heavy dependence on finite fossil fuels as our major source of energy, causing serious energy and environmental crisis such as emission of CO2 and NO x on the world. Hydrogen is attracted as a leading candidate for alternative future fuels because it has the potential to address the environmental and energy security issues associated with fossil hydrocarbon fuels. Solid oxide electrolysis cells (SOECs) are one of the promising technology for the efficient production of H2 from electricity because electrolysis at elevated temperatures is beneficial for both thermodynamic and kinetic reasons. Recent significant interest in steam electrolysis has been mainly concerned with performance, durability and degradation issues. In conventional SOE used for steam electrolysis, the most commonly used cathode and anode materials for oxide ion-conducting SOECs are Ni-YSZ (yttria-stabilized zirconia) and LSM (strontium-doped lanthanum manganites)-YSZ, respectively. But, these electrode materials suffer from several problems such as an intrinsic redox instability, agglomeration and coarsening of nickel particles for Ni-YSZ and a delamination and insufficient durability of LSM-YSZ during steam electrolysis. In this study, the layered perovskite oxides employed as potential ceramic cathode and anode for SOEC with dense LaGaO3 based electrolyte, showing a high performance and durability over 600 hours with no degradation in electrolysis mode.

A Novel Versatile Methodology for the Assessment of the Effects of Alternative Fuels on Engine Durability

Since the introduction of first generation biodiesel (Fatty Acid Methyl Esters, FAME) at blending rates in diesel of up to 7% vol., concerns were raised regarding engine component durability. The deposition rate on engine components appears to be related to specific biodiesel characteristics, not included in the EN14214 standard. This paper describes a test method developed that is able to predict the effects of specific fuels on engine components that are not possible to be revealed by initial fuel properties as tested according to fuel standards EN590 and EN14214. The method is able to simulate long engine operation within a feasible test duration with controllable acceleration of involved phenomena and in a cost effective manner including the use of limited amount of fuel and only engine components affected by the fuel degradation. The paper presents the developed method, the experimental setup configuration, fuel treatment, key operating conditions and operating protocol of the main test. Test results are being presented for both current market fuels of different characteristics as regards FAME content and presence of detergent additives as well as for experimental and reference fuel blends developed for the assessment of possible future fuels and fuel injection system configurations. The paper concludes that the specific method is able to provide information on the applicability and possible durability issues associated with the use of alternative fuels and advanced fuel injection system technologies under consideration and is a candidate to be implemented as a future fuel standard.

Nowoczesne materiały do przechowywania wodoru jako paliwa przyszłości

Nowoczesne materiały do przechowywania wodoru jako paliwa przyszłości