The utilization of retired wind turbine blades (RWTB) is important for the sustainable development of wind energy. Although pyrolysis enables efficient separation of organic polymers and fibers, the valorization of complex pyrolysis oil remains challenging. In this study, pyrolysis oil derived from RWTB was upgraded to high-energy-density cycloalkane fuels via catalytic hydrodeoxygenation (HDO) over a bifunctional Ru-NbOPO4 catalyst. Catalyst preparation and reaction conditions were systematically optimized, and the catalyst was characterized by SEM, XRD, N2 adsorption–desorption, NH3-TPD, Py-FTIR, and XPS. Under optimal conditions, the cycloalkane content in the HDO products reached 95.8%. The catalyst maintained high activity over five consecutive cycles, demonstrating excellent recyclability. Structural characterization revealed a sheet-like mesoporous NbOPO4 support with suitable Brønsted and Lewis acid sites. The mesoporous structure facilitated mass transfer, while Ru nanoparticles activated hydrogen for aromatic hydrogenation. Lewis acid sites associated with coordinatively unsaturated Nb species may promote the adsorption and activation of oxygen-containing intermediates and C–O bonds, whereas Brønsted acid sites originating from surface hydroxyl groups may facilitate proton-assisted dehydration. Overall, Ru-NbOPO4 effectively promoted the HDO of RWTB pyrolysis oil, reduced oxygen-containing compounds, and improved fuel quality, providing a promising pathway for the high-value utilization of retired wind turbine blades.
A series of ruthenium meso-aryl dipyrrinato complexes namely, [(p-R-C6H4)C(C4H3N)2Ru(p-cymene)Cl] [where, R = t-Bu (1a), C6H5 (1b), Br (1c), OMe (1d)] provide an efficient atom-economical single step access route to bioactive pyrimidines (2−20) (19 examples) from primary and secondary alcohols and amidines proceeding via dehydrogenative coupling of alcohols followed by selective C−C bond formation. The mass spectrometric and 1H NMR evidences corroborated the presence of ketone and aldehyde bound ruthenium hydride species, [(p-R-C6H4)C(C4H3N)2]Ru(p-cymene)(PhCOCH3)(H) (B)−1(a−d) and [(p-R-C6H4)C(C4H3N)2]Ru(p-cymene)(PhCHO)(H) (F)−1(a−d), in a proposed catalytic cycle. To rationalize the experimental findings and advance the understanding of ruthenium-catalyzed dehydrogenation, density functional theory (DFT) calculations were performed on the ruthenium meso-aryl dipyrrinato (1d) complex to elucidate the catalytic pathway. Mechanistic studies reveal that the orientation of carbonyl oxygen and the hydride-transfer pathway govern alcohol dehydrogenation, while Non-covalent interaction (NCI) analysis elucidates the interactions responsible for this behavior. β-hydride elimination from alcohol represents the key kinetic bottleneck in the reaction pathway.
Developing a green and efficient process for the catalytic amination of ethylene glycol (EG) to high-value-added ethyleneamines is of great significance for the chemical industry. In this work, an efficient hydrotalcite-derived Co-based catalyst was successfully prepared for the catalytic amination of EG to monoethanolamine, ethylenediamine, piperazine, aminoethylpiperazine, and hydroxyethylpiperazine, collectively referred to as the total amines. Balancing the conversion–selectivity trade-off, the optimized reaction at 180 °C delivered 25.8% EG conversion, 31.5% EDA selectivity, and 99.1% selectivity to the total amines. Characterization results indicated that La and P co-doping significantly enhanced the stability of the Co-based catalyst. DFT calculation results further confirmed that the dehydrogenation of the alcohols tends to follow the "alkoxyl" pathway, the dehydration elimination of the hydroxylamine-type intermediates tends to follow the "hydroxyl‑dehydration" pathway, and the hydrogenation of imine intermediates clearly prefer the "alkyl-imine" pathway on the Co(111) facet. This work provides a new approach for preparing high-value-added ethyleneamines using low-cost, readily available EG as the feedstock via catalytic amination, and holds great promise for industrial application.
FeNi/MoS2 heterostructure electrocatalysts are prepared using a two-step hydrothermal method, and the correlation between their structure and catalytic performance is systematically investigated. The successful compositing of FeNi and MoS2 has enabled the surface atoms of the catalyst to be exposed as much as possible. In addition, most previously reported FeNi/MoS₂ composites exhibited granular or stacked sheet-like morphologies. In comparison, the as-synthesized catalyst possessed a porous, nano-scale cauliflower-like morphology with abundant accessible active sites. This porous structure facilitated the exposure of electrochemically available active sites and further favored the enhancement of catalytic performance. The introduction of MoS2 effectively modulated the electronic structure of Fe and Ni, promoting interfacial charge transfer, which is speculated to optimize intermediate adsorption and thus improve the reaction kinetics. In electrochemical testing, FeNi/MoS2 exhibited an oxygen evolution reaction (OER) overpotential of only 175.4 mV (Tafel slope 34.69 mV·dec−1) at 10 mA·cm−2, and an hydrogen evolution reaction (HER) overpotential of 179.6 mV (Tafel slope 53.46 mV·dec−1), both significantly superior to those of the FeNi and NF control groups, this catalyst delivered competitive bifunctional performance metrics. Moreover, this catalyst exhibits high double-layer capacitance and low charge transfer resistance, indicating a larger electroactive surface area and faster electron transport. After 12 h of continuous electrolysis, the current density showed no significant decay, demonstrating excellent durability. Therefore, the synergistic interaction between FeNi and MoS2, the electronic regulation at the heterointerface, and the mass transfer advantages of the porous structure collectively enhance the catalytic activity, providing the new insights for the design of high-performance non-precious metal bifunctional electrocatalysts.
