Green diesel production from non-edible biomass oils provides an effective route for developing sustainable liquid fuels. In this work, Styrax confusus fruit oil was converted into diesel-range alkanes through hydrodeoxygenation over RuFe bimetallic catalysts supported on in-situ N-doped carbon. The N-doped carbon support was prepared from oil-pressing residues and fruit shells of Styrax confusus, enabling the utilization of residual biomass as natural carbon and nitrogen precursors without the addition of an external nitrogen source. A series of monometallic and bimetallic catalysts were prepared and evaluated for the hydrodeoxygenation of methyl stearate and Styrax confusus fruit oil. Among them, RuFe/NC exhibited the best catalytic performance. Under the optimized conditions of 240 ℃, 3 MPa H2, and 5 h, complete feedstock conversion was achieved, with a total alkane yield of 94.8 % and a C17–C18 alkane selectivity of 93.6 %. Characterization results from XRD, TEM, XPS, BET, and H2-TPR revealed that Ru and Fe formed closely contacted bimetallic species on the N-doped carbon support, while nitrogen species contributed to metal anchoring and dispersion. The introduction of Fe regulated the electronic structure of Ru. DFT calculations further confirmed that RuFe/NC exhibited modified hydrogen adsorption behavior, which favored hydrodeoxygenation while inhibiting cracking reactions. This study provides a sustainable strategy for the full-component utilization of Styrax confusus fruits and offers mechanistic insight into RuFe/NC-catalyzed green diesel production.

A sustainable strategy was developed to upgrade biodiesel (fatty acid methyl esters) from microbial lipids into green diesel (hydrocarbons) while valorizing waste byproducts. Waste yeast cell walls of Rhodosporidium toruloides were converted into nitrogen-doped activated carbon (NC) using their intrinsic nitrogen content, which served as a support for noble metal hydrodeoxygenation catalysts. Among four catalysts, Ru/NC delivered the best performance, achieving 100% conversion and 84.71% alkane yield in the hydrodeoxygenation of methyl stearate. Structural and theoretical analyses showed that electron transfer (1.03e–) from Ru to pyrrolic nitrogen sites. Additionally, Ru/NC exhibited stronger basicity and enhanced adsorption capacity for intermediate fatty acids. Applied to biodiesel from R. toruloides, Ru/NC reached 100% conversion and a C14–C18 alkane yield of 91.46%. This work presents a promising route for integrating waste utilization into biodiesel upgrading.

Herein, we have achieved successful preparation of atomically dispersed catalytic systems, liquid metal Ptx/Ga catalysts, which eliminate the need for reduction processes. Notably, the 0.5wt% Ptx/Ga catalyst exhibited exceptional stability in hydrogenation performance, achieving 100% conversion of stearic acid with an impressive 98.7% selectivity towards octadecane, especially with unprecedented stability over 19 recycling cycles. X-ray absorption spectra (XPS) and density functional theory (DFT) calculations unequivocally establish that isolated Pt atoms, benefitting from charge transfer from the Ga matrix, synergistically optimize Pt metal atom utilization, thereby efficaciously optimizing the d-band center and augmenting hydrogenation proficiency. Furthermore, isolated Pt configuration's weaker CO adsorption ability effectively mitigates concerns of catalyst poisoning and undesirable agglomeration, thereby engendering superior stability. The stronger adsorption with aldehyde and alcohol intermediates promotes the hydrogenation of stearic acid through hydrodehydration pathway, thereby ensuring a high carbon utilization economy. Overall, our work offers insight into the investigation of hydrogenation conversion of bio-derivatives over atomically dispersed catalytic systems.

Fundamental knowledge of the active site requirements for the activation of C-O bonds on heterogeneous catalysts is essential for the design of efficient hydrodeoxygenation catalysts. Pt-WOx (x < 3) catalysts have shown activity and selectivity for the C-O bond breaking of various biomass-derived oxygenates. Yet, the nature of the active sites and the structure-performance relationship have not been well understood because of the intimate coupling of multiple sites. Here, we construct a hybrid catalyst with integrated defective tungsten oxide (e.g., WO2.72) and Pt/C to investigate the role of multiple sites (e.g., metal sites, Bronsted acid, and oxygen vacancy) that are active toward the hydrogenolysis of esters to alkanes in Pt-WOx catalysts. Experimental and theoretical results suggest that oxygen vacancies derived from the defective tungsten oxide (WOx) supply coordinatively unsaturated sites to adsorb and activate the oxygen atom of the carbonyl group of esters, while Pt metal provides an active hydrogen atom for this process. More importantly, it is found that the hydroxyl derived from W-OH in WOx, as a typical Bronsted acid site, can contribute to the adsorption and activation of the C-O bond of esters. The synergistic effect of oxygen vacancies and Bronsted acid sites results in a remarkably efficient acyl C-O bond cleavage of esters, which boosts the hydrodeoxygenation of esters under mild conditions (T <= 200 degrees C). These insights into the structure-performance relationships offer rational methods for designing efficient catalysts for low-temperature hydrodeoxygenation of biomass-derived esters.

Herein, we successfully prepared the subnanometric Ni anchored on boron and nitrogen co-doped carbon, featuring vertically aligned molybdenum disulfide (MoSS) for hydrogenation conversion of fatty acid into alkanes. Remarkably, the Ni/MoS2@BNC catalyst with a relatively low Ni loading (approximately 1.0 wt%) exhibited outstanding performance and great stability, achieving complete conversion of fatty acid with octadecane and heptadecane selectivity of 94.6 % and 5.4 % at the condition of 245 degrees C, 3 MPa H2 and 6 h. Based on the density functional theory (DFT) calculations and experimental results, the excellent catalytic properties of Ni/MoS2@BNC catalyst are attributed to the synergistic effect between subnanometric Ni and N, B co-doped carbon material. This synergy creates abundant basic sites, modulates the electronic structure, and shifts the d-band center downward, which promotes a preferential adsorption of H2 and CH3CH2COOH, further enhancing the hydrogenation conversion of fatty acid into alkanes.

Herein, we present a synergistic catalytic approach utilizing Pt nanoparticles anchored on a graphitic carbon nitride (CN) for the selective hydrogenation of stearic acids into alcohols. The catalyst was prepared via a photodeposition method, ensuring the high dispersion of Pt nanoparticles on the surface of CN. Notably, the 0.48 wt% Pt-CN catalyst exhibits the best performance, achieving 100 % conversion of stearic acid into stearic alcohol with a yield of up to 89.6 % under optimized reaction conditions. The interaction between Pt nanoparticles and g-C3N4 support is confirmed experimentally by X-ray photoelectron spectroscopy (XPS) and theoretically by Bader charge analysis and density functional theory (DFT) calculations. Furthermore, in-depth investigations into the adsorption behavior unveil a pronounced synergistic effect between the loaded Pt nanoparticles and CN support, leading to enhanced adsorption capacities for acid molecules and hydrogen. Our findings not only provide insights into the design of novel catalysts for sustainable chemical transformations but also highlight the potential of carbon nitride-based catalysts in converting bio-derived acids into value-added alcohol products.

The efficient hydrogenolysis of esters to alkanes is the key protocol for producing advanced biofuels from renewable plant oils or fats. Due to the low reactivity of the carbonyl group in esters, a high reaction temperature (>250 degrees C) is the prerequisite to ensure high conversion of esters. Here, we report a highly dispersed MoOx-Ru/C bimetallic catalyst for the efficient hydrogenolysis of esters to alkanes under 150 degrees C. The optimal catalyst exhibits >99% conversion of methyl stearate and 99% selectivity to diesel-range alkanes, reaching a high rate of up to 2.0 mmol g(cat)(-1) h(-1), 5 times higher than that of Ru/C catalyst (MoOx/C is inert). Integrated experimental and theoretical investigations attribute the high performance to the abundant MoOx-Ru interfacial sites on the catalyst surface, which offers high activity for the C-O cleavage of esters. Furthermore, the dispersed MoOx species significantly weaken the hydrocracking activity of the metallic Ru for C-C bonds, thus yielding alkane products without carbon loss. This study provides a facile and novel strategy for the design of high-performance heterogeneous catalysts for the hydrodeoxygenation of biomass-derived esters to alkane products. (c) 2025, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

The hydrogenation of bio-based oil into biodiesel is a key strategy in reducing reliance on fossil fuels. However, efficient catalysts are needed to enable low-temperature hydrogenation reactions due to the current high-temperature requirement for bio-based oil hydrogenation. Here, bimetallic catalysts Rex-Ru/C for low-temperature hydrogenation of bio-based oils were prepared. The presence of Re oxides (ReOx) in the catalyst enhances the abundance of weak and medium acid sites, thereby facilitating the adsorption of H2. The DFT calculation shows the introduction of Re also improved the adsorption capacity of the catalyst for fatty acid methyl ester and H2. The Re0.25-Ru/C catalyst exhibits superior conversion, selectivity, and recyclability at low temperatures compared to the previously reported catalysts, achieving 100% conversion of methyl stearate with 100% selectivity toward n-heptadecane (C17) and n-octadecane (C18) (reaction conditions: 150 degrees C, 4 h, 2.5 MPa H2). Moreover, the catalyst also shows excellent hydrogenation activity toward various fatty acids or esters, including methyl palmitate, stearic acid, and palmitate at low temperatures. The Re0.25-Ru/C catalyst showed consistent recycling performance over 9 cycles. The decline in catalytic performance of the catalyst was primarily caused by a reduction in ReOx content, resulting in a decrease in acid site concentration. Consequently, there was reduced adsorption of H2 and oil on the catalyst.

To mitigate global carbon emissions, utilizing bio-based oils instead of petroleum for biodiesel production has emerged as a viable strategy. However, the development of efficient catalysts for the mild conversion of fatty acid esters (the mainly compounds of oils or fats) into diesel-range alkanes remains challenging due to the low reactivity of carbonyl group in esters. Herein, we report an efficient catalyst system for the hydrodeoxygenation of fatty acid esters into diesel-range alkanes under mild conditions over the RemNin@SiO2 catalyst. The catalyst containing a Re/Ni molar ratio of 1.0 showed the best catalytic performance, a 100

Al2O3-supported Ni-Mo as a low-cost and efficient bimetallic catalyst has been applied in the hydrodeoxygenation of plant oils or fats for production of high-quality hydrocarbon fuels, but it is still challenge to avoid the serious cleavage of C-C bonds caused by isolated single-metal Ni sites. Herein, we report a novel Al2O3-supported Mo-Ni catalyst (Mo-Ni@Al2O3) with Ni and Mo sites in close proximity to enhance the hydrodeoxygenation (HDO) selectivity of fatty acid esters. Compared with the conventional Mo-Ni/γ-Al2O3 catalyst showing high hydrogenolysis activity for C−C bonds, the Mo-Ni@Al2O3 catalyst exhibited higher HDO selectivity towards the diesel-range alkanes. Detailed characterizations reveal that during the synthesis of Mo-Ni@Al2O3 catalyst, the loaded Ni species were present in two forms after reduction in a H2 flow, one is the closely contact of Ni and Mo bimetallic sites and the other is NiAl2O4, which enhances the synergistic promoting effect between Ni and Mo sites and inhibits the presence of isolated metallic Ni active sites, thereby exhibiting the enhanced remarkably HDO selectivity towards target products.

Ruthenium -based catalysts have been widely used in the lignin depolymerization and polystyrene hydrogenolysis reactions due to its superior hydrogenolysis activity for C -O and C -C bonds. However, serious cleavage of C -C bonds at high temperatures greatly limits its application in the production of green biodiesel from the conversion of natural oils and bio-derived fatty esters. In this work, we found that introducing a suitable second less -reactive metal (e.g., Fe, Zn) can effectively suppress the hydrogenolysis activity of ruthenium (Ru) metal for C -C bonds and exhibit a high selectivity (>90 %) to diesel -range alkanes (C-15 -C-18 alkanes) in the conversion of fatty acid methyl esters (FAMEs) even at high reaction temperature (250 C-degrees) over the Ru1Fe0.5 catalyst, while an obvious cracking reaction was observed from 210 C over the monometallic Ru catalyst. Detailed characterization and theoretical calculation results reveal that the introduction of Fe species in the RuFe catalysts weakens the interaction between catalyst and the resulting alkanes, which inhibits the cracking of alkanes. Specifically, adding Fe species breaks the ensemble of Ru atoms and decreases the binding affinity of metallic Ru for H-2, which suppresses the activity of Ru metal for the hydrogenolysis of C -C bonds and exhibits a high selectivity to diesel -range alkanes. This research provides valuable information for improving the hydrodeoxygenation (HDO) selectivity of Ru-based catalysts while inhibiting its high hydrogenolysis activity for C -C bonds.

Selective hydrodeoxygenation is the central challenge in converting bio-derived fatty acids into fatty alcohols under mild conditions. Herein, an effective and highly selective carbon-supported NiMo catalyst (NiMo@C) was developed by the thermolysis Ni-based metal-organic frameworks (MOF) impregnated Mo species. At a low temperature of 160 degrees C, the stearic acid can be efficiently converted into corresponding stearic alcohols over the NiMo@C with about 97% selectivity at 100% reactant conversion, which is superior to the most reported catalysts containing noble catalysts. The excellent catalytic performance of NiMo@C catalyst was mainly attributed to the ordered arrangement of Ni in the MOF and the uniform loading of molybdenum salt, which leads to an ideal distribution of Ni and Mo after pyrolysis of the MOF. The carbon support also prevents the aggregation of metal particles, which promotes the dissociation of hydrogen and enhances the synergy between Ni and Mo sites. More importantly, the synthesized NiMo@C catalyst showed excellent reusability with no loss of activity after 15 consecutive runs due to the stability of the catalyst structure. This provides a useful and simple method for synthesizing highly efficiency and stable NiMo@C bimetallic catalysts, which can facilely and selectively hydrogenate the bio-derived fatty acids to corresponding alcohols under mild conditions.

Enhancing both the reactivity and durability of catalysts for the hydrogenation of bio-derived fatty acids is a formidable challenge.

The need to use hydrogen (H2) gas has increasingly become important due to the growing demand for carbon-free energy sources. However, the explosive nature of H2 gas has raised significant safety concerns, driving the development of efficient and reliable detection. Although 2D materials have emerged as promising materials for hydrogen gas sensing applications due to their relatively high sensitivity, the incorporation of other nanomaterials into 2D materials can drastically improve both the selectivity and the sensitivity of sensors. In this work, high-entropy alloy nanoparticles using non-noble metals were used to develop a sensor for H2 gas detection. This chemical sensor was realized by decorating 2D MoS2 surfaces with multicomponent body-centered cubic (BCC) equiatomic Ti-Zr-V-Nb-Hf high-entropy alloy (HEA) nanoparticles. It was selective towards H2, over NH3, H2S, CH4, and C4H10, demonstrating widespread applications of this sensor. To understand the mechanisms behind the abnormal selectivity and sensitivity, density functional theory (DFT) calculations were performed, showing that the HEA nanoparticles can act as a chemical hub for H2 adsorption and dissociation, ultimately improving the performance of 2D material-based gas sensors.

Imidazolium ionic liquid is a novel and efficient catalyst for biodiesel production from oleaginous yeast. However, the catalytic mechanism of how imidazolium ionic liquid works in the reaction is not clear. Herein, Density functional theory (DFT) was employed to investigate the catalytic mechanism of three imidazolium ionic liquids in esterification and transesterification reactions. Pathways containing three intermediates and two transition states were proposed for the two reactions. In the subsequent DFT calculation, PBE0-D3BJ functional and 6-31G* basis set were used to optimize the intermediates and transition states. Then the Gibbs free energy of the intermediates and transition states in each reaction step was calculated to obtain the energy barrier for each reaction. The calculation results showed that 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim][HSO4]) had the minimum energy barrier of 37.77 kcal/mol in esterification, and 1-sulfobutyl-3-methylimidazolium hydrosulfate ([HSO3-Bmim][HSO4]) had the minimum energy barrier of 20.80 kcal/mol in transesterification, which were consistent with previous experimental results. The catalytic mechanism validated in this study provides a new idea for subsequent optimization of imidazolium ionic liquid structure to improve their catalytic efficiency in biodiesel production from oleaginous yeast.

Ni3Fe clusters anchored on rutile (R-TiO2) were synthesized by hydrothermal (HT), coprecipitation (CP) and impregnation (IM) methods, and the catalytic performance of different NiFe/R-TiO2 catalysts were investigated for hydrogenation of fatty acid into alcohol. Notably, HT-NiFe/R-TiO2 catalyst, with the highest specific surface area and Ni3Fe nanoparticles dispersion, exhibited the best hydrogenation activity towards alcohol production, with complete conversion and yield reach of 92.5 % at 4 MPa H2, 210 celcius and 6 h. The structure-reactivity relationship was investigated by a series of catalysts characterization, DFT calculation and corroborated through hydrogenation performance evaluations. Anchoring Ni3Fe clusters onto highly dispersed basic site surfaces with different Ov concentrations can change the electron distribution and strength of the metal-support interaction, causing more stable adsorption of the H and acids molecular toward fatty alcohol production. This work provides further insight into the structure-activity of NiFe/TiO2 catalysts synthesized through different methods.

Catalytic transformation of fatty acids into fatty alcohols is the essential step to produce renewable energy and high-valuable chemicals from waste fatty acids. In this research, a series of Ni3Fe catalysts were synthesized to improve this transformation, specifically that the Ni3Fe anchored on TiO2 surface has performed excellent ac-tivity with a high alcohol yield reaching 91.2%. The structure-reactivity relationship between the Ni3Fe nano -particles on different crystal types of TiO2 (anatase: A-TiO2, rutile: R-TiO2) was investigated. It was found that the as-prepared Ni3Fe/R-TiO2 catalyst showed better catalytic performance than that of Ni3Fe/A-TiO2. Both experimental and density functional theory (DFT) computational results indicated that the interactions between Ni3Fe nanoparticles and R-TiO2 support have highly promoted the formation of oxygen vacancy (Ov), which plays an essential role in C-O and H-H cleavage, thus promoting the hydrogenation towards fatty alcohols. Furthermore, the catalyst reusability tests showed that Ni3Fe/TiO2 catalyst exhibited good stability over four times recycled and excellent suitability for industrial crude fatty acid conversion.

Waste oil, like waste cooking and acidic oil, are two promising carboxylic acids feedstocks that can be converted into hydrocarbons by the pyrolytic method, usually through DCO2 and DCO processes. DFT is employed to investigate the deoxygenation mechanism using octanoic acid as a model compound in this work. Additionally, pyrolysis of the above samples was carried out at atmospheric pressure, temperature below 773.15K. GC-MS, GC and TG-FTIR-MS test measures were used to analyze pyrolytic products. The DFT results reveal that pyrolysis conversion of waste oil was a direct and effective deoxygenation method. And high alkene content endowing pyrolytic oil greatly potential to upgrade for high-quality biofuel production. Finally, pyrolytic oil was upgraded by SAPO-11-Pd/C can increase the components of iso-hydrocarbons, further can faction cut to obtain three biofuel fractions. Fraction blending with fuels could decrease the cold filter plugging point of final fuels, dramatically improving the commercial value of pyrolytic oil and effectively solving the waste oil disposal problem.

Efficient deoxygenation for the bio-derived fatty acid is paramount to producing diesel-like alkane and usually requires harsh reaction conditions. Here, we reported an efficient conversion system for the photocatalytic conversion of fatty acid over Pt/TiO2 catalysts and acid conversion higher than 99.0% (yield nearly 84.5%) under the mild conditions 30 degrees C, 0.1 MPa H2, and 365 nm light. X-ray photoelectron spectroscopy (XPS) and Density Functional Theory (DFT) calculations suggest that the oxygen vacancies TiO2 can achieve the charge transfer from TiO2 support to Pt clusters. The electron-rich Pt cluster can promote hydrogen spillover to form a hydrogenrich surface. Thus, it leads to the photo-decarboxylation Cn-1 alkyl radical being amenable to proton hydrogenation to produce Cn-1 alkane. Detailed characterization demonstrates that 0.50 wt% Pt/TiO2 has superior photocatalytic performance. Introducing the Pt atoms can promote the formation the oxygen vacancies and reverse charge transfer, which determines the acid adsorption and conversion mechanism.