| Magnesium resources are rich in salt lakes in our country, but the development and utilization of them are very poor. How to transfer the abundant salt lake resources into products in order to bring up economic benefit is the problem that people pay attention to extremely. MgCl2·6H2O-C2H4(OH)2 system is a kind of mixed solution system, has an important value on preparation of anhydrous MgCl2 for electrolysis manufacturing of metal magnesium, magnesium ion rechargeable battery, ionic liquids based on magnesium and electrolyte. In this paper, we mainly focus on the research of Mg Cl2·6H2O-C2H4(OH)2 system, present the investigation of phase equilibrium of the system, it provides a theory foundation to comprehensive utilization magnesium resource in salt lakes. The content of the investigations in the paper and the results are as follows:1. In this paper, two kinds of novel single crystals were synthesized using the equilibrium liquid phase of MgCl2·6H2O-C2H4(OH)2 system, [Mg(EG)2(H2O)2]Cl2(1) and [Mg(EG)(H2O)6]Cl2(2), these complexes have been characterized by single-crystal X-ray diffraction. The analysis reveals that the central ion of these complexes have adopted the six-coordinated, the center magnesium cation of complex 1 is covalently bonded by four carboxyl oxygen atoms from four different C2H4(OH)2 molecules and two hydroxyl oxygen atoms from two coordinated water molecules, the center magnesium cation of complex 2 is covalently bonded by six hydroxyl oxygen atoms from six water molecules. The coordination geometry around the magnesium ion of the two complexes can be described as a slightly distorted octahedral configuration. These complexes have been characterized by IR analyses, elementary analyses, XRD, thermogravi-metric analyses.2. In this paper, dissolution and crystallization behavior of MgCl2·6H2O in C2H4(OH)2 were studied, the solubility curve of Mg Cl2·6H2O in C2H4(OH)2 was measured. Chemical analysis was used to determine the composition of the equilibrium liquid phase, XRD and chemical analysis were used to determine the composition of the equilibrium solid phase, to research and summarize some experience and basic laws from it. The physico-chemical properties such as density, refractive index, viscosity, and conductivity value of the equilibrium liquid phase under 30℃ in the system were determined, and the physico-chemical property vs composition /temperature diagrams of the equilibrium liquid phase were plotted. |
