1477-55-0Relevant articles and documents
Isophthalonitrile (IPN) hydrogenation over K modified Ni-Co supported catalysts: Catalyst characterization and performance evaluation
Liu, Chang,Wang, Tiefeng
, p. 63725 - 63733 (2014)
The hydrogenation of isophthalonitrile (IPN) to meta-xylylenediamine (m-XDA) is usually catalyzed by the Raney or supported Ni based catalysts in the presence of basic additive. Although the supported catalysts are safer than the Raney Ni catalysts, they have lower selectivity to m-XDA. This work revealed that the acid sites of NiCo/Al2O3 were responsible for the condensation reactions between amines and imines, which were the dominant side reactions. Besides the original acid sites on γ-Al2O3, the loading of Ni-Co introduced new acid sites, which had a greater contribution to the condensation reactions. The K modification significantly enhanced the selectivity to m-XDA by reducing the two kinds of acid sites. Due to the formation mechanism of new acid sites and the K modification mechanism on these sites, both the K loading and K impregnation sequence affected the catalytic performance. When 3.0 wt% K was introduced to NiCo/Al2O3 by co-impregnation (3KNiCo/Al2O3), the catalyst acidity decreased by 82%, and the selectivity to m-XDA increased from 45.5% to 99.9%. The superiority of the optimized catalyst 3KNiCo/Al2O3 was also confirmed when no basic additive was used.
Ni-Co-Cu supported on pseudoboehmite-derived Al2O3: Highly efficient catalysts for the hydrogenation of organic functional groups
Shi, Tianbao,Li, Hui,Yao, Lianghong,Ji, Weijie,Au, Chak-Tong
, p. 68 - 73 (2012)
Ni-Co-Cu catalysts supported on pseudoboehmite-derived Al2O 3 were developed for efficient hydrogenation of organic functional groups: CN and NO2 associated with benzene as well as CC in butynediol. Factors such as thermo-treatment of pseudoboehmite, Ni loading, Cu and Co content, and catalyst operating parameters were systematically studied. Among the catalysts, 20%Ni-3%Cu-5%Co/Al2O3 performed the best, showing 100% feed conversion and 84-99.8% selectivity of target products. Techniques such as N2 sorption measurement, scanning electron microscope, hydrogen temperature-programmed reduction and desorption, X-ray photoelectron spectroscopy, and in situ X-ray diffraction were used to characterize the catalysts. The superior performance of the catalyst can be attributed to synergetic interaction among the Ni-Cu-Co constitutes as well as enhancement of Ni2+ reduction and Ni0 dispersion that are resulted due to the co-presence of Cu and Co.
Role of acid sites and surface hydroxyl groups in isophthalonitrile hydrogenation catalyzed by supported Ni-Co catalysts
Liu, Chang,Hou, Ruijun,Wang, Tiefeng
, p. 26465 - 26474 (2015)
meta-Xylylenediamine (m-XDA) is industrially produced by the hydrogenation of isophthalonitrile (IPN) using Raney Ni/Co and basic additives. Compared with Raney Ni/Co, the supported Ni/Co catalysts are safer and have better mechanical strength. This work aimed at studying the catalytic performance of the supported Ni-Co catalysts in hydrogenation of IPN to m-XDA. The active sites for the condensation side reactions were studied using Ni-Co catalysts supported on different oxides and with different loadings. It was found that the acid sites catalyzed the condensation reactions between intermediate imines and amines. Two types of acid sites existed on the supported Ni-Co catalysts, namely, the original acid sites of the support and new acid sites formed by Ni/Co aluminates. In addition to acid sites, the surface hydroxyl groups on the oxide supports also catalyzed the condensation reactions, but were not active for the hydrogenation reaction. By increasing the Ni-Co loading, the selectivity to m-XDA was significantly enhanced, which was attributed to the suppression of both acid sites and hydroxyl groups. Compared to the low-loading catalysts (5Ni-1.25Co/Al2O3 and 5Ni-1.25Co/SiO2), the high-loading catalysts (20Ni-5Co/Al2O3 and 20Ni-5Co/SiO2) increased the m-XDA selectivity from ～45.5 to 99.9%.
Catalytic hydrogenation of isophthalonitrile (IPN) over supported monometallic and bimetallic catalysts
Liu, Chang,Li, Xiaodan,Wang, Tiefeng
, p. 57277 - 57285 (2015)
The hydrogenation of Isophthalonitrile (IPN) to meta-xylylenediamine (m-XDA) is usually catalyzed by RANEY or supported Ni based catalysts in the presence of a basic additive. The supported catalysts have better mechanical strength and are safer than RANEY Ni catalysts. This work aimed to study the catalytic performance of γ-Al2O3 supported Ni and Ni-M (M = Fe, Co, Cu) bimetallic catalysts in IPN hydrogenation. The H2-TPR results revealed that the introduction of a second metal enhanced the reducibility of Ni catalyst. The Ni-M bimetallic catalysts also had different metal dispersion, electronic properties and adsorption strength. Among Fe, Co and Cu, Fe showed the best promoting effect, which was attributed to the strong N-metal bonding and weak H-metal adsorption strength, which enhanced the catalytic activity and m-XDA selectivity. The catalytic performance also strongly depended on the Ni-Fe mass ratio. For the γ-Al2O3 supported Ni and Ni-M catalysts with a low Ni loading of 5 wt%, the rate constant kr increased from 0.024 mol0.2 L-0.2 min-1 over 5Ni/Al2O3 to 0.033 mol0.2 L-0.2 min-1 over 5Ni-1.67Fe/Al2O3, meanwhile the m-XDA selectivity increased from 34.7% to 49.5%. Over the Ni-Fe bimetallic catalyst with high metal loading, 20Ni-5Fe/Al2O3, a very high m-XDA selectivity of 99.9% was obtained.
METHOD FOR PRODUCING m-XYLYLENE DIAMINE
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Paragraph 0061-0072; 0074; 0079, (2021/08/13)
PROBLEM TO BE SOLVED: To provide a method for producing m-xylylene diamine that makes it possible to efficiently produce m-xylylene diamine by reducing the formation of by-products even when a reaction temperature is lowered in a hydrogenation reaction step. SOLUTION: In the presence of a catalyst with palladium carried on carbon and in the absence of ammonia and an amine compound (excluding a reaction product), 1,3-dicyanobenzene and hydrogen are reacted at 0°C or higher and 50°C or lower, and hydrogen is added to the 1,3-dicyanobenzene, producing m-xylylene diamine. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
Modulating: Trans -imination and hydrogenation towards the highly selective production of primary diamines from dialdehydes
Hao, Rui,Li, Lin,Liu, Fei,Qi, Haifeng,Su, Yang,Wang, Aiqin,Yang, Jingyi,Zhang, Leilei,Zhang, Tao
, p. 6897 - 6901 (2020/11/09)
Bio-based primary diamines are important building blocks for sustainable bio-polymers, but their synthesis remains challenging due to the high susceptibility to polymerization. Herein, we have developed a new strategy to suppress the polymerization by employing a more nucleophilic alkylamine to scavenge the dialdehyde and a Co/ZrO2 catalyst to regulate the trans-imination and hydrogenation activity. With this strategy, 2,5-bis(aminomethyl)furan (BAMF), a promising monomer for the production of new polyamides and polyureas, is successfully synthesized via the reductive amination of biomass-derived 2,5-diformylfuran (DFF) under a H2 and NH3 atmosphere with an unprecedentedly high selectivity up to 95%. This strategy is applicable to the reductive amination of other biomass-derived dialdehydes, thus paving a new way to bio-based diamine monomers. This journal is
Cobalt pincer complexes for catalytic reduction of nitriles to primary amines
Schneek?nig, Jacob,Tannert, Bianca,Hornke, Helen,Beller, Matthias,Junge, Kathrin
, p. 1779 - 1783 (2019/04/27)
Various cobalt pincer type complexes 1-6 were applied for the catalytic hydrogenation of nitriles to amines. Among these, catalyst 4 is the most efficient, allowing the reduction of aromatic as well as aliphatic nitriles in moderate to excellent yields.
Green and convenient protocols for the efficient reduction of nitriles and nitro compounds to corresponding amines with NaBH4 in water catalyzed by magnetically retrievable CuFe2O4 nanoparticles
Zeynizadeh, Behzad,Mohammad Aminzadeh, Farkhondeh,Mousavi, Hossein
, (2019/03/23)
Abstract: In this study, firstly, CuFe2O4 nanoparticles were prepared by a simple operation. The structure of the mentioned nanoparticles was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma-optical emission spectrometry, vibrating sample magnetometer and also Brunauer–Emmett–Teller and Barrett–Joyner–Halenda analyses. The prepared magnetically copper ferrite nanocomposite was successfully applied as a simple, cost-effective, practicable, and recoverable catalyst on the green, highly efficient, fast, base-free, and ligand-free reduction of nitriles and also on the affordable and eco-friendly reduction of nitro compounds with the broad substrate scope to the corresponding amines with NaBH4 in water at reflux in high to excellent yields. Graphical abstract: [Figure not available: see fulltext.].
Facile synthesis of supported Ru-Triphos catalysts for continuous flow application in selective nitrile reduction
Konrath, Robert,Heutz, Frank J.L.,Steinfeldt, Norbert,Rockstroh, Nils,Kamer, Paul C.J.
, p. 8195 - 8201 (2019/09/19)
The selective catalytic hydrogenation of nitriles represents an important but challenging transformation for many homogeneous and heterogeneous catalysts. Herein, we report the efficient and modular solid-phase synthesis of immobilized Triphos-type ligands in very high yields, involving only minimal work-up procedures. The corresponding supported ruthenium-Triphos catalysts are tested in the hydrogenation of various nitriles. Under mild conditions and without the requirement of additives, the tunable supported catalyst library provides selective access to both primary amines and secondary imines. Moreover, the first application of a Triphos-type catalyst in a continuous flow process is presented demonstrating high catalyst life-time over at least 195 hours without significant activity loss.
NICKEL DIATOMACEOUS EARTH CATALYST AND METHOD FOR PRODUCING THE SAME
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Paragraph 0072, (2018/11/21)
A nickel diatomaceous earth catalyst having a weight loss rate measured by hydrogen-TG at 400 to 600° C. of 0.05 to 2.0%.
