Hasil untuk "Fuel"

Jiazhan Li, Mengjie Chen, D. Cullen et al.

Jian Wei, Q. Ge, Ruwei Yao et al.

The direct production of liquid fuels from CO2 hydrogenation has attracted enormous interest for its significant roles in mitigating CO2 emissions and reducing dependence on petrochemicals. Here we report a highly efficient, stable and multifunctional Na–Fe3O4/HZSM-5 catalyst, which can directly convert CO2 to gasoline-range (C5–C11) hydrocarbons with selectivity up to 78% of all hydrocarbons while only 4% methane at a CO2 conversion of 22% under industrial relevant conditions. It is achieved by a multifunctional catalyst providing three types of active sites (Fe3O4, Fe5C2 and acid sites), which cooperatively catalyse a tandem reaction. More significantly, the appropriate proximity of three types of active sites plays a crucial role in the successive and synergetic catalytic conversion of CO2 to gasoline. The multifunctional catalyst, exhibiting a remarkable stability for 1,000 h on stream, definitely has the potential to be a promising industrial catalyst for CO2 utilization to liquid fuels. Direct hydrogenation of CO2 into liquid fuels can mitigate CO2 emissions and reduce the rapid depletion of fossil fuels. Here, the authors show an iron-based multifunctional catalyst that converts CO2to gasoline with high selectivity due to synergistic cooperation of multiple catalytic active sites.

K. Terrani

F. Martins, C. Felgueiras, M. Smitkova et al.

The use of fossil fuels as the main source of energy for most countries has caused several negative environmental impacts, such as global warming and air pollution. Air pollution causes many health problems, causing social and economic negative effects. Worldwide efforts are being made to avoid global warming consequences through the establishment of international agreements that then lead to local policies adapted to the development of each signing nation. In addition, there is a depletion of nonrenewable resources which may be scarce or nonexistent in future generations. The preservation of resources, which is a common goal of the Circular Economy strategy and of sustainable development, is not being accomplished nowadays. In this work, the calculation of indicators and mathematical and statistical analysis were applied to clarify and evidence the trends, provide information for the decision-making process, and increase public awareness. The fact that European countries do not possess abundant reserves of fossil fuels will not change, but the results of this analysis can evolve in the future. In this work, fossil fuel energy consumption, fossil fuel depletion, and their relationship with other variables, such as energy dependence and share of renewable energy in gross final energy consumption, were analyzed for 29 European countries. Furthermore, it was possible to conclude that many European countries still depend heavily on fossil fuels. Significant differences were not found in what concerns gross inland consumption per capita when the Kruskal–Wallis test was applied. It was possible to estimate that by 2050 (considering Jazz scenario) it will only remain approximately 14% of oil proven reserves, 72% of coal proven reserves and 18% of gas proven reserves. Given the small reserves of European countries on fossil fuels, if they need to use them, they will fast disappear.

E. Wachsman, K. Lee

Sihyuk Choi, C. Kucharczyk, Yangang Liang et al.

P. Strasser, S. Koh, T. Anniyev et al.

B. Logan

Liu Yang, Xiaofei Zeng, Wenchuan Wang et al.

R. Borup, J. Meyers, B. Pivovar et al.

Chuancheng Duan, R. Kee, Huayang Zhu et al.

Zongping Shao, S. Haile

W. Vielstich, A. Lamm, H. Gasteiger

G. Knothe

K. Kreuer

K. Rabaey, W. Verstraete

H. Fukuda, A. Kondo, H. Noda

A. Konnov, A. Mohammad, V. Kishore et al.

Abstract Accurate measurement and prediction of laminar burning velocity is important for characterization of premixed combustion properties of a fuel, development and validation of new kinetic models, and calibration of turbulent combustion models. Understanding the variation of laminar burning velocity with thermodynamic conditions is important from the perspective of practical applications in industrial furnaces, gas turbine combustors and rocket engines as operating temperatures and pressures are significantly higher than ambient conditions. With this perspective, a brief review of spherical flame propagation method, counterflow/stagnation burner method, heat-flux method, annular stepwise method, externally heated diverging channel method, and Bunsen method is presented. A direct comparison of power exponents for temperature (α) and pressure (β) obtained from different experiments and derived from various kinetic mechanisms is reported to provide an independent tool for detailed validation of kinetic schemes. Accurate prediction of laminar burning velocities at higher temperatures and pressures for individual fuels will help in closer scrutiny of the existing experimental data for various uncertainties due to inherent challenges in individual measurement techniques. Laminar burning velocity data for hydrogen (H2), gaseous alkane fuels (methane, ethane, propane, n-butane, n-pentane), liquid alkane fuels (n-heptane, isooctane, n-decane), alcohols (CH3OH, C2H5OH, n-propanol, n-butanol, n-pentanol) and di-methyl ether (DME) are obtained from literature of last three decades for a wide range of pressures (1–10 bar), temperatures (300–700 K), equivalence ratios and mixture dilutions. The available experimental and numerical data for H2 and methane fuels compares well for various pressures and temperatures. However, more experimental and kinetic model development studies are required for other fuels. Comparison of laminar burning velocity data obtained from different measurement techniques at higher initial pressures and temperatures showed significant deviations for all fuels. This suggests to conduct focused measurements at elevated pressure and temperature conditions for different fuels to enable the development of accurate kinetic models for wider range of mixtures and thermodynamic conditions.

O. Stoner, Jessica J. Lewis, I. Martínez et al.

Household air pollution generated from the use of polluting cooking fuels and technologies is a major source of disease and environmental degradation in low- and middle-income countries. Using a novel modelling approach, we provide detailed global, regional and country estimates of the percentages and populations mainly using 6 fuel categories (electricity, gaseous fuels, kerosene, biomass, charcoal, coal) and overall polluting/clean fuel use – from 1990-2020 and with urban/rural disaggregation. Here we show that 53% of the global population mainly used polluting cooking fuels in 1990, dropping to 36% in 2020. In urban areas, gaseous fuels currently dominate, with a growing reliance on electricity; in rural populations, high levels of biomass use persist alongside increasing use of gaseous fuels. Future projections of observed trends suggest 31% will still mainly use polluting fuels in 2030, including over 1 billion people in Sub-Saharan African by 2025. Household air pollution derived from cooking fuels is a major source of health and environmental problems. Here, the authors provide detailed global, regional and country estimates of cooking fuel usage from 1990 to 2030 and project that 31% of people will still be mainly using polluting fuels in 2030.

A. Pauline, K. Joseph

Abstract HydroThermal Carbonization (HTC) is a thermochemical process by which biomass is treated in aqueous environment under temperatures of 180–300 °C and self-generated pressure to produce solid fuel as hydrochar from wide range of organic wastes such as garbage, bio solids, agro residues and organic wastes from industrial operations. It is an economically efficient process as it eliminates the need for pre-drying and generates energy rich carbonaceous products. This paper reviews the hydrochar formation mechanisms of hydrolysis, dehydration, decarboxylation, condensation, polymerization and aromatization in terms of the critical hydrothermal parameters such as temperature, residence time, solid load, pressure, pH and aqueous conditions to derive fundamental understanding in the improvements required in HTC process design for waste to energy conversion. The identification of design protocols of HTC for solid fuel production is expected to expedite further research and field level scale up of this technology.