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As the aviation sector grows and fossil fuels are utilized, the environment and economy depend on biomass-based aviation fuel. This study investigated acid sites in aldol condensation to produce aviation fuel from biomass-derived aldehydes and ketones over the bifunctional catalyst Ni/HZSM-5. Due to its excellent 10-member ring channels structure, HZSM-5 yielded 63.81% of the targeted condensates as aviation fuel precursor. At 200 °C for 9 h, aldehydes and ketones were converted to 90.32% and 69.53% of the required condensates. Sodium ion-exchange HZSM-5 with different Brönsted acid site quantities was tested for condensation. Brönsted acid sites were the active center for aldol condensation of aldehydes and ketones, increasing product yield. In γ-Al 2 O 3 , the overall amount of Brönsted acid and Lewis acid was equivalent to that of HZSM-5, the amount of Lewis acid was much more. The yield of the targeted condensates over γ-Al 2 O 3 was only 46.11%, much lower than that of HZSM-5 (69.53%). Thus, Brönsted acid sites were better than Lewis acid sites for aldol condensation of aldehydes and ketones. The balance of active sites for aldol condensation and hydrogenation increased the intended alkane yield to 62.91% with 20 wt% Ni loading. This study involves improving biomass-based aviation fuel generation. • Aldol condensation of biomass-derives and hydrogenation over Ni/HZSM-5 was studied. • Higher yield of targeted condensates over HZSM-5 were up to 69.53% at 200 °C for 9 h. • Brönsted acid sites contributed more to the aldol condensation. • Ni loading is disadvantageous to aldol condensation but beneficial to hydrogenation. • A suitable Ni loading was determined considering both condensation and hydrogenation. [ABSTRACT FROM AUTHOR]

Selective deep hydrosaturation of polyaromatics has attracted significant attention in reinforcing the utilization of heavy resources and decreasing the emission of harmful particulate matters. Herein, supported Pt catalysts on diverse oxide supports (SiO 2 , TiO 2 , CeO 2) were prepared using an enhanced strong electrostatic adsorption tactics. Strong electronic metal-support interactions (EMSI) in Pt/TiO 2 and Pt/CeO 2 leaded to the well-dispersed electron-deficient Ptδ+ substances and intensified hydrogen spillover capacity, where the most Ptδ+ and spillover hydrogen were acquired on Pt/CeO 2 ascribed to the maximal EMSI and lower oxygen vacancy formation energy heightened the adsorption of metallic Pt. Moreover, the Ptδ+ species displayed promoted H 2 dissociation ability and boosted adsorption energy for aromatic. In phenanthrene hydrogenation, Pt/TiO 2 presented better activity and selectivity to deep hydrosaturation products than Pt/SiO 2 catalyst, indicating the enhancement of EMSI in hydrogenation. Meanwhile, the catalytic properties were further improved over Pt/CeO 2 exhibiting the highest rate of 3.63 × 10−4 mol·kg−1·s−1. It delivered almost 100% conversion and selectivity to deep hydrogenation at 220 °C because of the maximal of Ptδ+ species with superb dispersion and hydrogen spillover. Furthermore, the DFT calculations manifested the enhanced adsorption of aromatic on Ptδ+ species promoting deep hydrogenation. [Display omitted] • Enhanced strong electrostatic adsorption method was employed to prepare Pt catalysts. • Strong electronic metal-support interaction motivated the dispersion of supported metal. • Oxygen vacancies in reducible supports promoted electronic metal-support interaction. • Electron-deficient Ptδ+ and spillover hydrogen could facilitate aromatic deep hydrogenation. • The Pt/CeO 2 catalyst exhibited the best deep hydrosaturation properties for polyaromatic. [ABSTRACT FROM AUTHOR]

The second-generation bio aviation fuel production via Chemical Looping Gasification (CLG) of biomass combined with downstream Fischer-Tropsch (FT) synthesis is a possible way to decarbonize aviation sector. The CLG process has the advantage of producing undiluted syngas without the use of an air-separation unit (ASU) and improved syngas yield compared to the conventional gasification processes. This study is based on modelling the full chain process of biomass to liquid fuel (BtL) with LD-slag and Ilmenite as oxygen carriers using Aspen Plus software, validating the model results with experimental studies and carrying out a techno-economic analysis of the process. For the gasifier load of 80 MW based on LHV of fuel entering the gasifier, the optimal model predicts that the clean syngas has an energy content of 8.68 MJ/Nm3 with a cold-gas efficiency of 77.86%. The optimized model also estimates an aviation fuel production of around 340 bbl/day with 155 k-tonne of CO 2 captured every year and conversion efficiency of biomass to FT-crude of 38.98%. The calculated Levelized Cost of Fuel (LCOF) is 35.19 $ per GJ of FT crude, with an annual plant profit (cash inflow) of 11.09 M$ and a payback period of 11.56 years for the initial investment. • The developed model has been validated with experimental work. • CLG improves tar conversion and cold gas efficiency. • The model predicts better performance with LD slag as oxygen carrier. • Optimum FT reactor temperature for aviation fuel production is 220 °C. [ABSTRACT FROM AUTHOR]

In the present work we have performed a parameter study to maximize the yields of aviation bio-kerosene and renewable diesel range products obtained from the conversion of plant-oil triglycerides over Ni–W/SiO 2 –Al 2 O 3 , hydrocracking catalyst. Specific insights and changes in reaction mechanisms, with C O bond breaking favoured at increased pressures (> 60 bar) leading to depropanation/deoxygenation, as compared to C C bond breaking becoming favoured at reduced pressures (< 60 bar) leading to formation of lower range esters and short chain glycerides, are established for the first time using analytical techniques (GC, NMR and IR). The C C cleavage and low hydrogen partial pressures (< 60 bar) led to formation of unsaturated intermediates, which promoted cyclization, aromatization and coking reactions, which increased deactivation of catalyst. High space time yield with a maximum of 240 ml/(h ⋅ L catalyst ) for < C9 products and 350 ml/(h ⋅ L catalyst ) for C9–C14 products was observed at 420 °C temperatures. Stable catalytic performance was observed until 450 h of continuous operation with 25–30% yield of aviation bio-kerosene which meets all ASTM D 7566 standards. [ABSTRACT FROM AUTHOR]

Bimetallic Pd-Ru/ hydroxyapatite (HAP) catalysts were developed together with Zirconium phosphate (ZrP) to prepare aviation fuel range hydrocarbons by one-pot HDO from lignocellulose-derived C15 oxygenate. The effects of the catalyst composition, reaction time, initial H 2 pressure and reaction temperature on the HDO were explored. 84.24% C8-C15 alkanes could be obtained by Pd 0.6 -Ru 1.8 /HAP at 150 °C, 4 MPa H 2. The HDO pathway and the stability of the catalyst were also investigated. To explore the synergy of bimetals and the efficiency of the catalysts, a series of characterizations were conducted. The results verified that the bimetallic catalyst had a better adsorption capacity for the substrate, and the ruthenium external electron density raised due to the introduction of palladium, thereby enhancing the hydrodeoxygenation activity of the catalyst. [Display omitted] • Pd-Ru/hydroxyapatite were employed with Zirconium phosphate for HDO of C15 oxygenate. • Significant interaction and electron transfer were observed between Pd and Ru. • Bimetallic catalysts enhanced hydrodeoxygenation activity. • 84.24% C8-C15 alkanes were obtained under 150 °C and 4 MPa H 2. [ABSTRACT FROM AUTHOR]