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As the regulations related to greenhouse gases (GHG) emissions from fuel become stricter, fundamental changes are being effectuated to achieve the Paris Agreement agenda. Since the aviation sector contributes to 2.5 % of the global CO 2 emission, it is imperative to tackle this conundrum imminently by reducing the CO 2 emission from commercial flights, which are the main contributors to CO 2 emission in the aviation sector. Sustainable aviation fuel (SAF) has garnered tremendous attention in achieving carbon neutrality in the aviation sector. SAF is a suitable alternative since little to no modification of the aircraft is required for SAF usage. There are many challenges when it comes to implementing the use of SAF, including the large-scale production of SAF and the cost associated with the production of SAF. Therefore, this paper aims to provide an overview of various factors related to the global implementation of SAF, considering the latest supporting policy frameworks and from the perspective of feedstock. It examines how existing SAF pathways contribute to large-scale production and explores the role of emerging technologies—from potential feedstocks to the latest advancements. The paper delves into several emerging technologies, including hydrothermal liquefaction, aqueous phase reforming, pyrolysis, and photofermentation, discussing their potential in SAF production and the challenges they present. Furthermore, this paper analyses the life cycle assessment (LCA) and the techno-economic analysis (TEA) of different feedstocks and processes for SAF production. [Display omitted] • Existing policies associated with SAF growth and their limitations are reviewed. • Emerging technologies and challenges of sustainable aviation are explored. • Various feedstocks and ASTM-certified processes for SAF production are discussed. • Techno-economic and environmental aspects related to SAF are summarised. [ABSTRACT FROM AUTHOR]

In the context of the global response to climate change, methanol is receiving widespread attention as a potentially clean, renewable fuel. In this paper, the effects of injection timing and split injection strategy on the combustion process and emissions were investigated in methanol engines. The effect of mixture control on the ignition delay period was studied in detail. The results showed that when the injection timing was advanced to 95 °CA bTDC, the ignition delay period and combustion duration period were reduced by 28.96 % and 6.14 %, respectively. When the injection timing was delayed, the NO X emissions of the methanol engine were significantly reduced by 6.13 %–20.39 %. The use of split injection strategy enables the formation of a reasonably stratified fuel-air mixture in the cylinder. Under the optimized split injection strategy, the combustion duration was shortened by 0.93 %–14.58 %. The ignition delay period of the IT105S2 was shortened by 28.62 % compared with that of the original engine. In addition, the reasonable split injection strategy can effectively reduce the emission of formaldehyde and unburned methanol. This study provides an optimization direction for the application of methanol in the internal combustion engine for high efficiency and clean combustion. [Display omitted] • Split injection strategies and injection timing are studied on methanol engines. • NO X emission decreased by 6.13 %∼20.39 % as the injection timing is delayed. • Split injection facilitates the formation of a reasonably stratified mixture. • Combustion duration was reduced by 0.93 %∼14.58 % with split injection. • The formaldehyde and unburned methanol were reduced with spilt injection. [ABSTRACT FROM AUTHOR]

The paper presents a techno-economic comparison among five alternative process configurations for bio-methanol production from the gasification of residual forestry biomass. Process design and simulations are performed in Aspen Plus for mass and energy balance calculation, followed by preliminary sizing and economic analysis. Process schemes include a gasification island (state-of-the-art low-pressure gasification compared against a high-pressure gasifier) with syngas conditioning and compression, heat recovery, syngas composition adjustment (by CO 2 capture or addition of hydrogen produced by electrolysis), methanol synthesis and purification and a heat recovery cycle for power generation. CO 2 capture is performed with conventional chemical absorption in the benchmark cases, while low-temperature partial condensation of CO 2 is modeled in the advanced scenario. Methanol output is 14–15 kt/y in the CO 2 capture cases and 36 kt/y in the H 2 addition option. Configurations with a pressurized gasifier and phase-change-based CO 2 separation are the most efficient ones, with a primary energy efficiency of 50 % and a Levelized Cost of Methanol (LCOM) of 700 €/t MeOH. In comparison, LCOM increases to 730 €/t MeOH in the case with conventional capture or between 792 €/t MeOH and 831 €/t MeOH (depending on the CCS technology) if the gasification pressure is conservatively reduced to 2.5 bar. In the H 2 addition scenario, LCOM increases to 821 €/t MeOH due to the significant impact of the electricity consumption for H 2 production, (only partly compensated by the increased methanol production). Scenarios with CO 2 capture feature negative CO 2 emissions, in the range −1.64 to −1.84 t CO2eq /t MeOH , as a result of the capture and storage of biogenic CO 2 (BECCS approach). • Study of 5 bio-methanol configurations with CO 2 Capture and Storage or H 2 addition. • Process design and simulation of high- and low-P biomass gasification to methanol. • Partial liquefaction CO 2 capture and benchmarking against chemical absorption. • Minimum Levelized Cost of MeOH (700 €/t) for high-P gasifier and low-T CO 2 removal. • Negative net fossil CO 2 emissions of biomass-to-MeOH process due to BECCS. [ABSTRACT FROM AUTHOR]

Recently, a novel lightweight cork with enhanced thermal stability has been prepared using a respiratory impregnation method. In this paper, the thermal stability and decomposition of two kinds of cork CS-P (Quercus suber) and CV-P (Quercus variabilis B1) and corks that infused silica aerogel in cells CSS-P (Quer cus suber) and CSV-P (Quercus variabilis B1) were systematically studied, and their decomposition mechanisms were proposed. The results showed that the decomposition was inhibited at 200 °C, and the pyrolysis was significantly inhibited at the main pyrolysis stage (400 °C). Interestingly, the evolved gaseous products and their evolution models have also changed. Specifically, CO 2 and aldehyde emissions were significantly reduced in the main pyrolysis stage, reducing environmental pollution. Silica aerogel filler plays a catalytic role in the pyrolysis process, thus increasing the output of some value-added products (such as aromatics), which is suitable as the appropriate raw material or source of olefins to produce aliphatic rich pyrolysis biofuels. In general, the yield of biochar and bio-oil can be adjusted under low environmental pollution by loading silica aerogel and adjusting pyrolysis temperature. Corks that infused silica aerogel in cells may be a promising raw material for the production of biochar and biofuel through pyrolysis and contribute to the environmental and economic sustainability of the cork production industry. [Display omitted] • The pyrolysis thermal behavior of cork cells filled with silica aerogel was explored. • The emission of CO 2 and aldehydes decreased significantly during the main pyrolysis stage. • Silica aerogel filler plays a role in catalyzing the yield of valuable by-products during pyrolysis. • This work provides a novel and effective method to convert and manage biological waste resources. [ABSTRACT FROM AUTHOR]