Subnanometric Cu Clusters on Atomically Fe-doped MoO2 for Furfural Upgrading to Aviation Biofuels

Single cluster catalysts (SCCs) are considered as versatile boosters in heterogeneous catalysis due to their modifiable single cluster sites and supports. In this work, we report subnanometric Cu clusters dispersed on Fe-doped MoO2 support for biomass-derived furfural upgrading. Systematical characterizations suggest uniform Cu clusters (composing four Cu atoms in average) are homogeneously immobilized on the atomically Fe-doped ultrafine MoO2 nanocrystals (Cu4/Fe0.3Mo0.7O2@C). The atomic doping of Fe into MoO2 leads to significantly modified electronic structure and consequently charge redistribution inside the supported Cu clusters. The as-prepared Cu4/Fe0.3Mo0.7O2@C shows superior catalytic performance in the oxidative coupling of furfural with C3~C10 primary/secondary alcohols to produce C8~C15 aldehydes/ketones (aviation biofuel intermediates), outperforming the conventionally prepared counterparts. DFT calculations and control experiments are further carried out to interpret the structural and compositional merits of Cu4/Fe0.3Mo0.7O2@C in the oxidative coupling reaction, and elucidate the reaction pathway and related intermediates.

Performance and Emissions of Drop-In Aviation Biofuels in a Lab-Scale Gas Turbine Combustor

There is a growing need for drop-in biofuels for gas turbines for enhanced energy security and sustainability. Several fuels are currently being developed and tested to reduce dependency on fossil fuels while maintaining performance, particularly in the aviation industry. The transition from traditional fossil fuels to sustainable biofuels is much desired for reducing the rapidly rising CO2 levels in the environment. This requires biofuels to be drop-in ready, where there are no adverse effects on performance and emissions upon replacement. In this study, the performance and emissions of four different aviation drop-in biofuels were evaluated. They include UOP HEFA-SPK, Gevo ATJ, Amyris Farnesane, and SB-JP-8. These aviation biofuels are currently being produced and tested to be ready for full or partial drop-in fuels as the replacement of traditional jet fuels. The characteristic performance of each fuel from the prevaporized liquid fuels was performed in a high-intensity (20 MW/m3-atm) reverse flow combustor. The NO emissions showed near unity ppm levels for each of the fuels examined with a minimum at an equivalence ratio of ∼0.6, while CO levels were in the range of 1000–1300 ppm depending on the fuel at an equivalence ratio between 0.75 and 0.8. For an equivalence ratio range between 0.4 and 0.6, NO and CO emissions remained very low (between 1–2 ppm NO and 2400–2900 ppm CO) depending on the fuel. The examined biofuels did not show any instability over a wide range of equivalence ratios from lean to near stoichiometric condition. These results provide promising results on the behavior of these drop-in aviation biofuels for use in high-intensity gas turbine combustors providing stability and cleaner performance without any modification to the combustor design.

Performance and Emissions of Drop-in Aviation Biofuels in a Lab Scale Gas Turbine Combustor

There is a growing need for drop-in biofuels for gas turbines for enhanced energy security and sustainability. Several fuels are currently being developed and tested to reduce dependency on fossil fuels while maintaining performance, particularly in the aviation industry. The transition from traditional fossil fuels to sustainable biofuels is much desired for reducing the rapidly rising CO2 levels in the environment. This requires biofuels to be drop-in ready, where there are no adverse effects on performance and emissions upon replacement. In this study the performance and emissions of four different aviation drop-in biofuels was evaluated. They include: UOP HEFA-SPK, Gevo ATJ, Amyris Farnesane, and SB-JP-8. These aviation biofuels are currently being produced and tested to be ready for full or partial drop-in fuels as the replacement of traditional jet fuels. The characteristic performance of each fuel from the prevaporized liquid fuels was performed in a high intensity (20 MW/m3-atm) reverse flow combustor. The NO emissions showed near unity ppm levels for each of the fuels examined with a minimum at an equivalence ratio of ∼0.6, while CO levels were in the range of 1000–1300 ppm depending on the fuel at an equivalence ratio between 0.75–0.8. For an equivalence ratio range between 0.4 and 0.6, NO and CO emissions remained very low (between 1–2ppm NO and 2400–2900ppm CO) depending on the fuel. The examined biofuels did not show any instability over a wide range of equivalence ratios from lean to near stoichiometric condition. These results provide promising results on the behavior of these drop-in aviation biofuels for use in high intensity gas turbine combustors providing stability and cleaner performance without any modification to the combustor design.

The Use of Aviation Biofuels as an Airport Environmental Sustainability Measure: The Case of Oslo Gardermoen Airport

<p>In recent times, there has been a growing trend by airports and airlines to use aviation biofuel as an environment sustainability measure. Using an instrumental qualitative case study research design, this paper examines the evolution of sustainable aviation fuels at Oslo Airport Gardermoen. Oslo Airport Gardermoen was the first airport in the world to offer the first airport in the world to offer aviation biofuels to all airlines in 2016. The qualitative data were examined by document analysis. The study found that the use of sustainable aviation biofuels has delivered tangible environmental benefits to Oslo Gardermoen Airport. The usage of aviation biofuels has enabled the airport, and the airlines using sustainable aviation biofuels, to reduce their greenhouse gases by 10-15%. Also, as part of Norway’s efforts to reduce greenhouse gas emissions, the Norwegian Government have mandated that the aviation fuel industry must mix 0.5% advanced biofuel into jet fuel from 2020 onwards. Norway’s Ministry of Climate and Environment’s goal is that by 2030, 30% of the airline fuel will be sustainable in nature and will have a positive climate effect. Avinor, the operator of Norway’s airports, has a goal that by 2030, 30 % of aviation fuel supplied in Norway should be sustainable biofuel – this follows the Norwegian government’s mandate.</p>

Human Health Impacts of Aviation Biofuel Production: Exploring the Application of Different Life Cycle Impact Assessment (LCIA) Methods for Biofuel Supply Chains

The life cycle human health (HH) impacts related to aviation biofuels have been understood in a limited way. Life cycle impact assessment (LCIA) methods for assessing HH are often associated with a high level of uncertainty and a low level of consensus. As a result, it remains challenging to perform a robust assessment of HH impacts with a suitable LCIA method. This study aims to systematically compare six commonly used LCIA methods for quantifying HH impacts, in order to empirically understand the potential impacts of aviation biofuel production on HH and how the results are affected by the choice of methods. Three aviation biofuel production pathways based on different feedstocks (sugarcane, eucalyptus, and macauba) were analyzed and compared to fossil aviation biofuels, on the basis of a functional unit of 1 MJ aviation fuel. The majority of the LCIA methods suggest that, in respect to midpoint impacts, macauba-based biofuel is associated with the lowest impacts and eucalyptus-based biofuel the highest; whereas at endpoint level, the results are more scattered. The LCIA methods agree that biomass conversion into aviation biofuel, H2 production, and feedstock cultivation are major contributors to life cycle HH impacts. Additionally, we provide a guideline for determining an appropriate method for assessing HH impacts.