| It is quite important to remove the sulfur compounds in the liquid fuels, not only for the current environmental protection but also for future development. Adsorptive desulfurization technology has attracted intense interest of researchers for its advantages such as it can be conducted under milder conditions and it is environmental protection. And the key point of adsorptive desulfurization technology is the adsorbents used. Metal-organic frameworks (MOFs) are crystalline materials comprising by metal sites and organic ligands via coordinative bonds. They have exhibit bright prospect in many fields such as gas adsorption, gas storage, catalysis, asymmetric separation, fluorescence, and so on, for their large specific surface area, high porosity, adjustable pore size and shape and easy modification of the organic ligands. However, the traditional syntheses of metal-organic frameworks exist some disadvantages, such as high energy consumption, long reaction time, complex equipments and so on. Thus it is particularly important to find a facile and environmental protection method which also shows well desulfurization effect. The works in this paper were carried out under this background.The paper mainly includes the following parts:1. Cu-BTC is successfully synthesized via stirring chemical method. The effects of the reaction temperature, reaction time during the reaction process are studied. And the materials synthesized are used for the removal of DBT in the liquid oil to explore their adsorptive property. By using Cu-BTC for the adsorption of different concentrations of DBT and 100 ppm four kinds of sulfides (DBT, Th, BT,4,6-DMDBT) with different structure, the maximum adsorption capacity and mechanism of adsorption are studied. The regeneration performance of the Cu-BTC is also studied. The experimental results show that the optimal reaction conditions are 80 ? and 2 hour. Using Langmuir adsorption curve fitting, the maximum adsorption capacity of Cu-BTC is 28.6 mgS/gMOF. It is advantaged for sulfide with large heat enthalpy of absolute value because that the adsorption is an exothermic process. Cu-BTC can be renewable use many times via methanol soxhlet extraction.2. Four kinds of metal-organic frameworks (Cu-BTC, Cu-BDC, Zn-BTC and Zn-BDC) were synthesized via acid-alkali method. And they were used for removal of DBT in liquid oil to explore their desulfurization performance. Water and ethanol were also used as the solvent in the synthesis of the MOFs to study the impact of solvent in this method. The experimental results show that MOFs can be successfully synthesized. In addition, when changing the molar ratio of metal sites and organic ligands (namely M/L) in the Zn-BDC, other materials with different phase were produced. Among the four kinds of MOFs, Cu-BTC shows the best effect of sulfur removal (8 mgS/gMOF). The XRD patterns of Cu-BTC, Cu-BDC, Zn-BTC and Zn-BDC synthesized in water under ultrasound for an hour show low crystallinity or unidentified peaks. When taking ethanol as the solvent, only Cu-BTC is synthesized successfully in an hour. We deem that both the solubility of ligands in the solvent and the kinds of metal sites have important influence for the successful synthesis of MOFs via acid-alkali method. |
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