Mo 2 FeB 2 -based cermets exhibit promising industrial manufacturing applications due to their excellent mechanical properties, higher oxidation resistance, and thermal stability. In this study, ternary boride solid solution powders of Mo 2 (Fe x , Ni 1– x )B 2 were successfully prepared with a unique technique via employing B 4 C powder as a boron source, Mo, Fe, and Ni powders as metal sources as well as Ca powder as the decarburization agent. The effect of the Fe/Ni ratio on the phase composition, morphological evolution and average grain size of powders was studied. The shift of diffraction peak in the XRD results and the homogeneous distributions of Mo, Fe, Ni, and B by the EDS energy spectrum validated the successful synthesis of ternary boride solid solution powders. The morphology of solid solution powders varied depending on the Fe/Ni ratio. For compositions with Fe/Ni ratios of 10 : 0, 7 : 3, and 5 : 5, the ternary solid solution powders exhibited pronounced spherical grains with average grain sizes of approximately 3, 1, and 1 μm, respectively. Conversely, when the Fe/Ni ratios were 3 : 7 and 0 : 10, the solid solution powders exhibited mixed morphologies of spherical (with diameters of approximately 1 μm) and prismatic grains (with lengths of about 8 μm and diameters of around 3 μm), corresponding respectively to the tetragonal and orthorhombic crystal structures of Mo 2 NiB 2 . Using ultrafine Mo powder as a raw material to boost reaction kinetics resulted in the product's stable phase being orthorhombic Mo 2 NiB 2 . Nonetheless, at a Fe/Ni ratio of 3 : 7, the product still consisted of orthorhombic and tetragonal Mo 2 NiB 2 phases.
Shiqing Wang,Xiaocheng Lan,Boyang Liu,Babar Ali,Tiefeng Wang
Graphical Octylamine synthesis : Ni x Fe 1 /Al 2 O 3 was used as catalyst for 1-octanol amination and provided the highest yield among the reported nonprecious metal catalysts. The generation of Ni−FeO x interactions provided sufficient Fe 2+ /Fe 3+ −O 2− sites for the activation of 1-octanol. Meanwhile, the cooperation between Ni site and Lewis acid-base pairs significantly enhanced the amination of 1-octanol to 1-octylamine. The synthesis of 1-octylamine, a primary platform molecule, remained a great challenge in catalysis. In this work, Ni x Fe 1 /Al 2 O 3 was used for direct amination of 1-octanol to 1-octylamine. Catalyst evaluation indicated that the promotion effect of Fe/Ni ratio on the catalytic amination activity followed a volcano curve while the selectivity to 1-octylamine was positively correlated with the Fe loading. Compared with the Ni/Al 2 O 3 catalyst, the amination activity was increased by 2.8 times by optimizing the Fe/Ni ratio to 0.33, and the selectivity to 1-octylamine was increased from 84.0 % to 96.3 % when increasing the Fe/Ni ratio from 0 to 1. Based on catalyst characterizations, the good performance of Ni x Fe 1 /Al 2 O 3 was ascribed to the combined modification effect of the NiFe alloy and Ni−FeO x interface. The FeO x species enriched on the Ni particle surface provided sufficient Fe 2+ /Fe 3+ −O 2− sites for the activation of 1-octanol, and the cooperation between Ni sites and Lewis acid-base pairs enhanced the amination of 1-octanol to 1-octylamine. This work sheds new light on the design of Ni-based catalysts without using a noble metal for primary amine preparation.
危险品化学品经营许可证（带存储）