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The second-generation biodiesel is a clean, green and renewable energy. Herein, NiMo/γ-Al 2 O 3 catalysts were prepared by different methods and used for hydrodeoxygenation of fatty acid methyl ester (FAME) to produce C 15 –C 18 alkanes. The Al–Ni spinel (NiAl 2 O 4) and NiMoO 4 species can be formed during the impregnation method, while NiAl 2 O 4 and NiMoO 4 can be inhibited by co-precipitation method. The Ni3+ species on the catalyst surface from impregnation and co-precipitation method was assigned to NiMoO 4. Ni15Mo5/γ-Al 2 O 3 -CP (co-precipitation method) with smaller particle size of active metal oxides, large pore size, and more contents of low chemical valence states from active metal species (Ni2+ and Mo4+) shows a higher hydrodeoxygenation performance than Ni15Mo5/γ-Al 2 O 3 -IM (impregnation method). The liquid yield, conversion, oxygen removal efficiency, and selectivity of C 15-18 alkanes over Ni5Mo5/γ-Al 2 O 3 -CP are 76%, 100%, 99.05%, and 92.45%, respectively. It also shows a stable catalytic performance during 200 h test. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Al from SAPO-11 is substituted by in-situ substitution of transition metals. • Fe3SAPO-11 shows a unique morphology and suitable pore structure properties. • A small particle of Pt x Sn y alloy with high dispersion was prepared by using PVP. • Pt 1 Sn 1 alloy shows a strong adsorption energy of H and PA by DFT calculation. • Pt 1 Sn 1 /Fe3SAPO-11 can run as long as 1300 h with a stable catalytic ability. Green biodiesel, a clean and renewable fuel, is often encouraged to use as the substitute for fossil fuel. Herein, a new strategy of in-situ isomorphic substitution of Al from SAPO-11 was reported to synthesize a series of M−SAPO−11 molecular sieves by the way of well controlling the substitution amount of transition metals, e.g. , Fe, Co, Ni, Cu, and Zn. Owing to the unique morphology of spherical particles stacked layer by layer as well as the suitable pore structure properties, Pt/Fe3SAPO-11 showed a remarkable catalytic performance containing efficiency of deoxygenation with 100 %, selectivity of C 15 -C 18 alkanes with 99.6 %, and selectivity of iso -C 15 -C 18 alkanes with 34.8 % in one-step hydrotreatment process of fatty acid methyl ester. Through adding Sn and optimizing the atomic ratio of Sn/Pt alloy, the selectivity of iso -C 15 -C 18 alkanes over Pt 1 Sn 1 /Fe3SAPO-11 catalyst increased from 34.8 % to 62.7 %. Pt 1 Sn 1 and Pt 2 Sn 3 alloy catalysts prepared by hydrothermal method using polyvinylpyrrolidone displayed a small particle size of 2 nm, and more contents of low chemical states on Pt and Sn species. Pt 1 Sn 1 alloy exhibited a stronger adsorption energy of H and carbonyl oxygen (propionic acid) than Pt 2 Sn 3 alloy by DFT calculation. Besides, Pt 1 Sn 1 /Fe3SAPO-11 with a stable catalytic ability can run as long as 1300 h in a mild reaction condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method one-step reduction method without H 2 for catalyst preparation was proposed. • The AC-15 catalyst showed the high selectivity of bio-jet fuel and green diesel of 48.35 % and 51.05 %. • Co-effect of ZSM-5 and AC-15 enhanced isomerization and aromatization to produce bio-jet fuel. • After 4th cycle, the selectivity of bio-jet fuel and green diesel remains relatively high. The conversion of non-edible oils such as fatty acid methyl esters (FAME) into green and renewable liquid fuels align with the current trend of sustainable development. However, traditional processes often involve multi-step process to prepare catalyst and require high-pressure hydrogen. This study reports a strategy for the in-situ preparation of MnFeCoNiCu/C catalyst, enabling the one-step conversion of FAME into bio-jet fuels and hydrocarbon-based diesel under solvent-free and low-pressure conditions. The effect of active metal loading, reaction temperature, hydrogen pressure, and ZSM-5 zeolite addition on the catalytic performance was investigated. Under the conditions of reaction temperature 350 ℃ and hydrogen pressure 2 MPa, the conversion rate of FAME reaches 100 %, and the selectivity of bio-jet fuel and green diesel is 48.35 % and 51.05 %, respectively. A small number of olefins, cycloalkanes, and aromatics can also be detected in the products. After the 4 cycles of AC-15 catalyst, the selectivity of bio-jet fuel and diesel are 40.09 % and 39.81 %, respectively. The above research work provides a mild and efficient method for the preparation of renewable bio-jet fuel and green diesel. [ABSTRACT FROM AUTHOR]

One-step hydrotreatment of fatty acid methyl ester (FAME) was conducted to produce the green biodiesel over Pt/SAPO-11. Four key operating parameters including temperature, pressure, hydrogen-ester volume ratio (H/E) and liquid hourly space velocity (LHSV), based on the response surface methodology (RSM)-central composite design (CCD), were selected to optimize with five levels, which improved the production of the green biodiesel. The analysis of variance (ANOVA) explained the reliability of the optimization model well. A mathematical model with a second order quadratic equation was built to predict the production of the green biodiesel. The liquid yield, deoxygenation rate, and selectivity of C 15-18 alkanes are 72 wt%, 100%, and 98.87%, respectively, under the optimization conditions of temperature at 380 °C, pressure at 4 MPa, H/E ratio at 800 NmL·mL−1 and LHSV at 1.0 h−1. It is also shown that Pt/SAPO-11 remains a stable catalytic performance during 120 h test. Finally, a reaction pathway revealed that the decarbonylation is a key pathway during one-step hydrotreatment process. [Display omitted] • The green biodiesel was prepared by one-step process over Pt/SAPO-11. • Key operating parameters of one-step process were optimized by using RSM-CCD. • A second order quadratic equation was set to predict selectivity of C 15-18 alkanes. • Under the optimal conditions, Pt/SAPO-11 showed a good stability of 120 h. [ABSTRACT FROM AUTHOR]