| Hydrate technology has potential applications in water resources, environmental protection, gas storage and transportation, petrochemical industry, biochemical pharmaceutics and many other areas. However, due to the slow formation rate of hydrate, the long induction time , the low gas fraction in gas hydrate and other factors; the application of hydrate technology was restricted. So more and more researchers try to use various additives to improve the formation rate of hydrate. To find a suitable additive to promote hydrate nucleation has become the focus of hydrate technology. In recent years, a new type of porous crystalline materials have been studied and synthesized, zeolite imidazole framework (ZIF), which has the similar topology of zeolite. Researchers have found that the powder of 5A molecular sieves can promote the formation of THF hydrate and improve the temperature of hydrate crystallization.Whether ZIF also can promote hydrate formation is worthy to study.Zeolite imidazole framework (ZIF) is mainly prepared by solvent-thermal method. Despite the long reaction time, single crystal can be obtained for structural analysis. In order to shorten the synthesis time, we prepared ZIF by using microwave synthesis technology. Comparing to the traditional microwave synthesis, there was some modification, such as the addition of aging process of reaction solution and microwave heating for two times. Owing to this modification the yield and crystallinity of the product. had been improved. M-ZIF prepared by using advanced microwave synthesis method was in the form of rod shape. According to the results of elemental analysis and XRD, it can be confirmed that M-ZIF had the same structure as that of ZIF-61 which was synthesized by Yaghi. Under certain conditions of the total material concentration and reaction time, the structures of the products were the same when the material ratio was changed, but the crystallinity, the yield and particle size were different. When the molar ratio of Zinc nitrate to Imidazole was 1:7, the yield of the product after second microwave was the highest(45%). When the molar ratio of Zinc nitrate to Imidazole was 1:12, the crystallinity of the product after second microwave was the highest and the particle size was the biggest(44um). The Langmuir specific surface area of M-ZIF was 15m2/g. The adsorption amount of nitrogen by M-ZIF at 78k and 1 bar was 6.6mg/g. The adsorption amount of methane at 300k and 1 bar was 9.85mg/g. The adsorption amount of carbon dioxide at 300k and 1 bar was 25mg/g. The adsorption amount of gases by M-ZIF showed that the diameter of M-ZIF is much smaller than nitrogen molecules. So it's consistent with the XRD results.M-ZIF was applied to the process of hydrate formation. The promotion effect of M-ZIF on hydrate nucleation was studied. Since hydrate nucleation process is strongly exothermic process, the thermal conductivity of M-ZIF will directly affect hydrate formation. So the thermal conductivity of the solution containing M-ZIF was studied. The result showed that the thermal conductivity of glycol was increased by 10% due to the addition of 0.05% M-ZIF. By magnetic stirring and ultrasonic dispersion together 0.01%M-ZIF was added to THF (tetrahydrofuran) solution. The induction time of THF hydrate with 0.01% M-ZIF was 0.5-1h which was 0.5h shorter compared with pure THF hydrate. The results by means of the direct observation showed that: when the drive force of hydration was small (such as low cooling rate, low subcooling ), THF hydrate without M-ZIF was formed after several hours and its induction time is stochastic; while THF hydrate with M-ZIF was formed after several minutes and there is a certain reproducibility. Therefore, the addition of M-ZIF not only promoted the hydrate formation, but also solved the stochastic problem of hydrate formation...
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