| With the increasing emphasis on environmental protection in China's environmental regulations,the nitrogen content of oil products is increasingly limited.How to remove nitrides from oil products and reduce pollution at the source has become a hot spot in the field of chemical and environmental research.In this thesis,1,2-dimethylimidazole,1-benzyl-2-methylimidazole and1-vinylimidazole were used as raw materials to synthesize three types of imidazole-type ionic liquids?ILs?:monocationic,dicationic and polyionic liquids.The ILs structures were characterized by means of Proton nuclear magnetic resonance?1H-NMR?spectra and Fourier-transform-infrared?FTIR?spectra?KBr compression?.The effects of reaction time,ratio,temperature,and recycle times on the denitrification efficiency were investigated by liquid-liquid extraction and solid phase extraction.The research results are described as follows:1.Nine kinds of mono-cationic imidazole bisulfates were synthesized and their removal efficiencies of quinolines and quinones in simulated oils were investigated,while three of them namely as[C6MMIM]HSO4,[C6BzMIM]HSO4 and[C6VIM]HSO4 were chosen for deep research.The removal performance of the three ionic liquids to the denitrification to quinoline and quinone in simulated oils was investigated under different conditions,such as reaction ratios,temperatures,reaction times,and cycle times.The results shown that the three imidazolium ionic liquids have a promising effect on the removal of quinoline and hydrazine,and indicate consistency in the removal of quinoline and hydrazine.The best denitrification conditions are undertaken near room temperature in 30 min with 1:5?w/w?ratio of ionic liquid to oil,and the denitrification efficiency can reach more than 80%.At the same time,the ionic liquid can still keep good efficiency in its five recycle processing.2.Nine double cationic liquids were synthesized.It has shown that the denitrification capacity of the vinyl imidazole double cationic liquid series was higher than that of the series of1,2-dimethylimidazolium double cationic liquids and 1-benzyl-2-methylimidazolium double cationic liquids.The effects of vinylimidazole double cationic liquids on the denitrification efficiency under different reaction temperatures,reaction times,reaction ratios and cycle times were investigated.It was found that the denitrification efficiency of the double cationic liquid was higher than that of the mono cationic liquid,while the reaction temperature and the reaction ratio had a great influence on the denitrification efficiency.With the increase of the recycle times,the denitrification efficiency also decreased rapidly.The optimum denitrification conditions preferred at 35°C for 40 min with 1:5 ratio of ionic liquid to oil,and the denitrification efficiency of C6-?VIM?2-HSO4 was 96%.3.Three kinds of magnetic poly?ionic liquids?were synthesized by using bisvinylimidazolium ionic liquid as monomer.The magnetic poly?ionic liquids?showed good morphology,stability,magnetic properties and high efficiency of denitrification.The study showed that the influence of reaction time and reaction temperature was particularly small,and it was important that the denitrification efficiency drop was very low after 5 recycle times.The denitrification efficiency is as high as 75%when the ratio of magnetic polyionic liquid to oil is 1:20.A denitrogenation of real diesel is performed for 30 min at room temperature.The nitrogen removal method has the advantages of simple operation,convenient recovery of ionic liquid,and repeated use of the ionic liquid.The method is suitable for industrial production,which have broad application prospects for denitrification of oil products. |
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