Study On The Removal Of Basic Nitrogen And Non Basic Nitrogen By Acid Deep Eutectic Solvent

Nitrogen oxides emitted after the combustion of oil products are the main cause of smog formation.In the face of increasingly strict environmental protection requirements,research and development of green methods for deep denitrification of oil products has become an urgent task.The deep eutectic solvent extraction method used in this paper removes the nitrogen compounds in oil products,which breaks the limitations of other nitrogen removal methods that require high operation,high risk,and large equipment investment and low nitrogen removal rate.The deep eutectic solvents?DESs?as extractant have low toxicity and can be used repeatedly for many times.Compared with other denitrification processes,the deep eutectic solvent denitrification has great application prospects.In this paper,three deep eutectic solvents?DESs?were synthesized,and the basic and non-basic nitrides in the simulated oil were removed by extractive denitrification.?1?PEG-200/p-TsOH deep eutectic was prepared by mixing and dissolving two raw materials of polyethylene glycol 200?PEG-200?and p-toluenesulfonic acid?p-TsOH?in a molar ratio of 1:1.It was characterized by Fourier transform infrared spectroscopy?FT-IR?,1H nuclear magnetic resonance?¹H NMR?and thermogravimetric analysis?TGA?,and its nitrogen removal performance was investigated using quinoline and indole in simulated oil as researching aim.The experimental results show that the removal rate of quinoline is 98.48%and the removal rate of indole is 97.54%under the conditions of extraction time of 30 min,ratio of solvent to oil of1:10 and extraction temperature of 30?.After the deep eutectic solvent was recovered four`times,the nitrogen removal rates of the quinoline and the indole in simulated oil still reached 97.14%and 93.38%,respectively.?2?CH₃COOH/ZnCl₂deep eutectic solvent was prepared by mixing and dissolving two raw materials of glacial acetic acid?CH₃COOH?and zinc chloride?Zn Cl₂?according to a molar ratio of 1:1.It was characterized by Fourier transform infrared spectroscopy and ¹H nuclear magnetic resonance,and its nitrogen removal performance was investigated using quinoline and indole in simulated oil as researching aim.The experimental results show that the removal rate of quinoline is 98.75%and the removal rate of indole is93.73%under the conditions of extraction time of 25 min,ratio of solvent to oil of 1:5 and extraction temperature of 30?.After the deep eutectic solvent is recovered three times,the nitrogen removal rates of the quinoline and the indole in simulated oil can still reach more than 70%,respectively.?3?N-methylimidazole?C₄H₆N₂?and fluoboric acid?BF₄?are mixed and dissolved at a molar ratio of 1:1 to prepare methylimidazole tetrafluoroboric acid?[Hmim]BF₄?.Then the[Hmim]BF₄and lactic acid?C₃H₆O₃?are mixed and heated at a molar ratio of 1:1 to prepared[Hmim]BF₄/C₃H₆O₃deep eutectic solvent.It was characterized by Fourier transform infrared spectroscopy and ¹H nuclear magnetic resonance,and its nitrogen removal performance were investigated using quinoline and indole simulated oil as researching aim.The experimental results show that the removal rate of quinoline is 98.18%,and the removal rate of indole is 91.56%under the conditions of extraction time of 30 min,ratio of solvent to oil of 1:5,and extraction temperature of 20?.After the deep eutectic solvent was recovered four times,the nitrogen removal rates of the quinoline and the indole in simulated oil still reached 97.86%and 76.51%,respectively.