7786-30-3Relevant articles and documents
NOVEL ORGANO-MAGNESIUM COMPOUNDS AND THEIR USE
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Page/Page column 11; 15, (2021/11/26)
The present invention relates to novel organo-magnesium compounds obtained by reaction of dialkyl-magnesium compounds and carbodiimides and their use as precursors for the preparation of further magnesium compounds and catalysts.
Controlled synthesis of Mg(OH)2 nanorods using basic magnesium chloride as precursor
Chai, Shu-Jing,Luo, Bi-Jun,Wu, Hai-Hong,Wu, Dan,Lu, Shao-Yan,Zhang, Qi
, p. 90 - 101 (2021/07/07)
Mg(OH)2 nanorods were successfully prepared by two-step method. The precursor was obtained by hydrolyzed the MgCl2 in NH3·H2O solution, and then, it transformed into Mg(OH)2 nanorods by a simple solvothermal method without any surfactant or catalyst. The influences of synthesis parameters on the morphological characteristics and sizes of Mg(OH)2 nanoparticles were investigated, such as the proportion of EtOH–H2O solvent, the reaction temperature, and the treatment time. XRD and FESEM were used to characterize the structure, morphology, and composition of the samples. This method is lower costing, simple and environmentally benign, thus, it should be easy to be scaled up for industrial production.
In-situ observation on the magnesiothermic reduction of TiCl4 around 800 °C by microfocus X-ray fluoroscopy
Kishimoto, Akihiro,Uda, Tetsuya
, (2021/05/06)
In the industrial smelting process for titanium metal, liquid TiCl4 is supplied on molten magnesium and reduced to porous titanium in a closed steel or stainless steel container at 800–900 °C. In the present study, in-situ observation on the magnesiothermic reduction of TiCl4 was performed by microfocus X-ray fluoroscopy. We successfully observed that the molten magnesium creeps up on container walls rapidly and that porous titanium is mainly deposited and grows on the walls by reduction of gaseous TiCl4 by the magnesium. This unique behavior of magnesium is attributed to the capillary action of molten magnesium through pores of titanium deposited on the walls.
Kinetically Controlled Low-Temperature Solid-State Metathesis of Manganese Nitride Mn3N2
Rognerud, Erik G.,Rom, Christopher L.,Todd, Paul K.,Singstock, Nicholas Ryan,Bartel, Christopher J.,Holder, Aaron M.,Neilson, James R.
, p. 7248 - 7254 (2019/09/30)
The synthesis of inorganic metal nitrides poses a challenge due to the low reactivity of N2 gas at low temperatures, yet entropy driven formation of N2 gas at high temperatures. In contrast, synthetic approaches using more activated forms of nitrogen can be used to overcome the inertness of N2, but increased exothermicity can also result in diminished stoichiometric control and the activation of deleterious competing pathways. Here, kinetically controlled solid-state metathesis reactions are used to prepare Mn3N2 without the use of experimental conditions that increase the chemical potential of nitrogen and are known to produce phase impurity (e.g., NH3, N2-based plasma, azides, or high pressure). The solid-state metathesis reaction between MnCl2 and Mg2NCl or Mg3N2 is shown to generate Mn3N2, a phase on the border of stability. Highly exothermic control reactions performed with Li3N, Ca3N2, and Ca2NCl yield poorly crystalline, nitrogen-deficient Mn-N phases and N2 gas. The reactions with Mg2NCl and Mg3N2 do not self-propagate and have the lowest predicted free energies of reaction. A series of reactions performed at different times and temperatures, as well as in situ synchrotron X-ray diffraction, illustrate the importance of kinetic competence, and the results implicate the mechanism for this competence: the formation of a solid-solution, MgxMn1-xCl2, between the halide precursor (MnCl2) and the halide product (MgCl2) coupled to a mildly exothermic reaction. Kinetically controlled solid-state metathesis continues to provide an avenue toward the synthesis of materials that cannot be prepared under traditional, high-temperature ceramic methods.
Ionic liquids as an efficient medium for the mechanochemical synthesis of α-AlH3 nano-composites
Duan,Hu,Ma
, p. 6309 - 6318 (2018/04/23)
Aluminum hydride (AlH3) is one of the most promising hydrogen storage materials that has a high theoretical hydrogen storage capacity (10.08 wt%) and relatively low dehydriding temperature (100-200 °C). In this work, we present a cost-effective route to synthesize the α-AlH3 nano-composite by using cheap metal hydrides and aluminum chloride as starting reagents and to achieve liquid state reactive milling. The LiH/AlCl3 and MgH2/AlCl3 reaction systems were systemically explored. The phase identification of the obtained products was carried out by XRD and the morphology observed by TEM characterization. It was found that the α-AlH3 nano-composite can be successfully synthesized by reactive milling of commercial AlCl3 and LiH in a neutral ionic liquid ([2-Eim] OAc). Based on XRD analysis and TEM observation, an average grain size of 56 nm can be obtained by the proposed mechanochemical process. By setting the isothermal dehydrogenation temperature between 80 and 160 °C, the as-synthesized α-AlH3 nano-composite exhibits an advantage in hydrogen desorption capacity and has fast dehydriding kinetics. The hydrogen desorption content of 9.93 wt% was achieved at 160 °C, which indicates the potential utilization of the prepared nanocomposite in hydrogen storage applications.
Synthesis and properties of tetra-(4-tert-butyl-5-nitro)phthalocyanines
Rodionov,Maizlish,Shaposhnikov
, p. 96 - 101 (2016/03/12)
The interaction of 4-tert-butyl-5-nitrophthalonitrile with a series of metal acetates has yielded the corresponding metal phthalocyaninates. The treatment of magnesium tetra(4-tert-butyl-5-nitro)phthalocyaninate with hydrochloric acid has afforded tetra(4-tert-butyl-5-nitro)phthalocyanine. Spectral properties of the prepared macrocycles have been studied. The nature of the organic solvent and the complex forming metal marginally affect the position of the Q band in the electron absorption spectra of the studied compounds. It has been demonstrated that the prepared phthalocyanines can dye polymer materials and are catalytically active towards oxidation of a model sulfur-containing compound.
Polyethers as potential electron donors for Ziegler-Natta ethylene polymerization catalysts
Pirinen, Sami,Pakkanen, Tuula T.
, p. 177 - 183 (2015/02/19)
Poly(ethylene glycol) (PEG) and poly(tetrahydrofuran) (PTHF) were studied as possible electron donors for heterogeneous Ziegler-Natta catalysts employed for ethylene polymerization. Two synthetic routes were applied for the preparation of the catalysts by mixing the polyether and TiCl4 with δ-MgCl2 support in the same step or at different stages of the catalyst synthesis. The Fourier transform infrared spectroscopy (FT-IR) studies revealed a clear interaction between PEG and δ-MgCl2 inducing changes in the chain conformation of the polyether. If PEG was added at the same stage with TiCl4, a yellow PEG/TiCl4 complex was formed and the activity of the catalyst was decreased. A partial decomposition of PTHF to tetrahydrofuran (THF) in contact with δ-MgCl2 was evidenced from the FT-IR and nuclear magnetic resonance spectroscopy data. The decomposition could be induced by the Lewis acid sites or by possible organomagnesium compounds present in the synthesized δ-MgCl2. However, the decomposition did not have a negative effect on the polymerization behavior of the prepared catalysts, when compared to the reference catalysts where THF was initially used as a donor. The catalysts prepared with polyethers as electron donor showed good activity in ethylene (around 1000 kgP/molTi h) and in ethylene/1-hexene (around 1600 kgP/molTi h) polymerizations.
Silicon nanoparticles obtained via a low temperature chemical "metathesis" synthesis route and their lithium-ion battery properties
Wang, Liangbiao,Lin, Ning,Zhou, Jianbing,Zhu, Yongchun,Qian, Yitai
, p. 2345 - 2348 (2015/02/05)
Silicon (Si) nanoparticles have been prepared by a "metathesis" reaction of magnesium silicide (Mg2Si) and zinc chloride (ZnCl2) in an autoclave at 300°C. The as-prepared Si nanoparticles exhibit a reversible capacity of 795 mA h g-1 at a current density of 3.6 A g-1 over 250 cycles.
Effect of Zn and Zr addition on the synthesis of an AlH3/MgCl2 nanocomposite and its de-hydriding properties
Congwen, Duan,Lianxi, Hu,Yu, Sun
, p. 17104 - 17108 (2015/03/30)
This paper presents the preliminary findings of the effects of 3d transition metals on the synthesis of an AlH3/MgCl2 nanocomposite and its de-hydriding properties. The average grain size of as-milled AlH3 is 4-6 nm with a desirable hydrogen desorption content of 9.69 wt%, indicating that AlH3 is a promising hydrogen-storage material. This journal is
Solid state synthesis of nano-sized AlH3 and its dehydriding behaviour
Duan,Hu,Xue
, p. 3466 - 3474 (2015/06/25)
Aluminum hydride (AlH3) has a high gravimetric hydrogen capacity (10.1 wt%) and has attracted considerable attention due to its potential application for hydrogen storage. Up to now, almost all the routes developed for the synthesis of AlH3 are energy-consuming and economically impractical for mass production. In this study, a cost effective route of solid state reactive milling was proposed to synthesize AlH3 using aluminum chloride and cheap metal hydrides as starting reagents, with the LiH/AlCl3, MgH2/AlCl3, and CaH2/AlCl3 reaction systems being experimentally investigated. The reaction progress and products during reactive milling were characterized by XRD and 27Al NMR, and the morphology as well as the microstructure of the as-milled samples by SEM and TEM, respectively. It was found that nano-sized γ-AlH3 could be synthesized by reactive milling with commercial AlCl3 and nanocrystalline MgH2 as reagents. Based on the XRD and NMR analyses as well as the TEM observation, the average size of the γ-AlH3 phase in the as-synthesized γ-AlH3/MgCl2 nanocomposite was estimated to be about 8.5 nm. By an isothermal dehydrogenation test, the as-synthesized γ-AlH3 was found to have a quite high hydrogen desorption capacity and fast kinetics, with a hydrogen desorption amount of about 9.71 wt% within 9080 s at 220 °C.
