| Hydrogen as one of the main object of study in the field of new energy, it is widespread concern and attention all around the world. Hydrogen storage technology is an important area of research. Solid hydrogen storage materials due to their high quality and density hydrogen storage, hydrogen storage stable performance, and can be repeatedly used, etc. has become the focus of research in Hydrogen Storage Materials, aluminum hydride compound is one of them. In the conventional production method, there generally require high pressure at high temperature, high purity of raw materials and equipment requirements, this brings some difficulties for its widely application.In this paper, proposed a method with aluminum powder, halogenated hydrocarbons, hydrogen, etc. as raw materials, using different initiators activation reaction of aluminum powder at atmospheric pressure. It is explore the effect of solvent for preparation of organic aluminum at different temperatures, reaction time, material ratio and other conditions. Preparation of an organic solution of aluminum in toluene as a dispersing agent under conditions of reaction at 39 ℃, using iodine and aluminum chloride as an initiator, the reaction time is about 40 min, and mole ratio of 1: 4. And the actual effect is explored by IR and activity tests, it indicates a high activity of aluminum organic solution. Then study the AlH3 prepared by organic solution of aluminum and sodium hydride in liquid phase conditions. The effect prepared AlH3 is better under molar ratio of 1: 1, ether as a solvent, moderately elevated of temperature to 45 ℃, the time is between 2h-4h, 3h for crystal conversion. Intermediate product is characterized by IR and XRD diffraction, the results show that the AlH3 can be detected presence in the product, but is more difficult to separate Preparation AlH3 experimental conditions studied using NaAlH4 instead of LiAlH4 by composite and sulfuric acid, etc. By comparison found that the same problem is difficult to separate.During the study preparation AlH3, it is found NaAlH4 in the product by increasing the amount of sodium hydride, and have launched a study. By changing the amount of sodium hydride, the reaction temperature and time, select a different solvent conditions. It found that the temperature at 85℃, the organic aluminum and sodium hydride molar ratio of about 1: 2, react for about 3h, tetrahydrofuran or ethylene glycol dimethyl ether as solvent repeatedly after purification, it can get a very good purity and crystal structure of the sample NaAlH4. Its performance has been characterized by IR, XRD, SEM, MS, DSC and elemental analysis and melting point apparatus and other means. The solution was subjected to solid-liquid separation after the activation of organic aluminum, respectively, to react with sodium hydride. The reaction mechanism was studied in detail. The results showed that NaAlH4 has a good stability obtained by this method. Its performance and commercial products as well, or better than, its amount of hydrogen exploded put up 3.2wt%. Mechanistic studies suggest that this method also has characteristics of the composite method and direct method. A variety of reaction is carried out at the same time in liquid phase. It has a high utilization of raw materials, and the yield can up to 95%. |
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