[C4mim]HSO4离子液体脱除页岩油柴油馏分中氮化物的研究

合成了1-丁基-3-甲基咪唑硫酸氢盐离子液体,并以氮含量高的抚顺页岩油柴油为原料考察其脱氮性能。分别研究了温度、油/IL质量比、水/IL、反应时间、沉降时间等因素对总氮和碱性氮脱除效率的影响。试验结果表明：该离子液体具有较好的脱氮性能,在抽提温度30℃、油剂质量比7:1、水剂质量比2:1、抽提时间20min、沉降时间2h的条件下,碱氮和总氮脱除率分别为90%、71%,且离子液体回用5次,其碱氮脱除率仍可达到74%。     

Removal of nitrogen compounds from fuel oils using imidazolium-based ionic liquids

Several imidazolium-based ionic liquids (ILs) with different anionic characteristics were investigated to determine their denitrogenation performances from the model oil containing indole or quinoline. Experiment results showed that [C₄mim]HSO₄ exhibited an excellent denitrogenation performance, obtaining about 99% N-removal efficiency from the model oils. In addition, removal efficiency of quinoline and indole after five cycles of ionic liquid can reach 98.4% and 96.3%, respectively. The effects of the extraction temperature, time, and IL/oil mass ratio on the denitrogenation process are discussed in detail.     

[Bmim]Br/FeCl3离子液体脱除页岩油柴油中的氮化物

合成了低粘度的离子液体[Bmim]Br/FeCl3,采用红外光谱对其结构进行表征,并考察其对高氮含量的抚顺页岩油柴油馏分中氮化物的脱除效果。结果表明：[Bmim]Br/FeCl3离子液体具有良好的脱氮性能,在萃取温度30 ℃、剂油质量比1:1、萃取时间30 min、静置时间2h的条件下,[Bmim]Br/FeCl3对柴油馏分中碱氮和总氮的脱除率分别为95.29%和89.76%,对应的柴油馏分中的碱氮和总氮含量分别由5454μg/g,9832μg/g降低到257μg/g,1006μg/g。且该离子液体经回收重复使用4次后,在剂油质量比1:7的条件下,碱氮脱除率仍能达到60%。     

配位离子液体NMP-0.5ZnCl2脱除柴油中的碱性氮化物

以NMP和ZnCl2为原料合成一种配位离子液体,并用红外光谱进行结构表征。分别以喹啉模型油和焦化柴油为原料考察该离子液体的碱氮脱除性能。结果表明NMP-0.5ZnCl2离子液体具有良好的脱氮性能,在萃取温度50 ℃、剂油质量比1：2、萃取时间30min的条件下,喹啉脱除率可达99.68%;焦化柴油经过5级萃取脱氮后,碱氮脱除率可达91%以上,碱氮含量由536μg/g降至47μg/g。此外,配位离子液体NMP-0.5ZnCl2在回收利用4次后,喹啉脱除率仍可达到96.73%,具有较好的重复使用性能。     

Synthesis of amphiphilic peroxophosphomolybdates for oxidative desulfurization of fuels in ionic liquids

Three amphiphilic peroxophosphomolybdates [C₄mim]₃PMo₄O₂₄, [C₈mim]₃PMo₄O₂₄ and [C₁₆mim]₃PMo₄O₂₄ were synthesized and characterized. These catalysts were used for extraction and catalytic oxidative desulfurization of fuel with H₂O₂ as an oxidant and ionic liquid [C₄mim]BF₄ as an extractant. It was found that [C₁₆mim]₃PMo₄O₂₄ showed the highest catalytic activity and the sulfur content could decrease to 7.5 ppm. In contrast, the desulfurization system shows very low performance without H₂O₂ or ionic liquid. The detailed reaction conditions were optimized including reaction time, temperature, the dosage of H₂O₂ and catalyst, and different sulfur compounds. After the reaction, the catalysts and the ionic liquid can be cycled 8 times with a little decrease in desulfurization efficiency.     

低共熔离子液体脱除焦化柴油中的碱性氮化物

制备低共熔离子液体四乙基溴化铵-丙二酸（物质的量比1:1）,采用红外光谱和核磁共振氢谱对其结构进行表征,并以焦化柴油为原料考察该离子液体对碱性氮化物的脱除性能。结果表明四乙基溴化铵-丙二酸具有较好的碱氮脱除性能,在萃取时间30min,萃取温度30℃,剂油质量比1:1和沉降时间120min的条件下,碱氮脱除率可达93.6%,焦化柴油的碱氮含量降低到37μg/g。且该低共熔离子液体在回收利用4次后,在剂油质量比1:7的条件下,对碱性氮化物的脱除率仍可达62.9%,有较好的重复使用性能。     

Amorphous TiO2-supported Keggin-type ionic liquid catalyst catalytic oxidation of dibenzothiophene in diesel

Supported ionic liquid(IL) catalysts [C_nmim]_3PMo_(12)O_(40)/Am TiO_2(amorphous TiO_2) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization(ECODS) system. Characterizations such as FTIR, DRS,wide-angle XRD, N_2 adsorption–desorption and XPS were applied to analyze the morphology and Keggin structure of the catalysts. In ECODS with hydrogen peroxide as the oxidant, it was found that ILs with longer alkyl chains in the cationic moiety had a better effect on the removal of dibenzothiophene. The desulfurization could reach 100% under optimal conditions, and GC–MS analysis was employed to detect the oxidized product after the reaction. Factors affecting the desulfurization efficiencies were discussed, and a possible mechanism was proposed. In addition, cyclic experiments were also conducted to investigate the recyclability of the supported catalyst. The catalytic activity of [C_(16)mim]_3 PMo_(12)O_(40)/Am TiO_2 only dropped from 100% to 92.9% after ten cycles, demonstrating the good recycling performance of the catalyst and its potential industrial application.     

Oxidative Desulfurization of Dibenzothiophene Catalyzed by VO(acac)2 in Ionic Liquids at Room Temperature

A simple extraction and catalytic oxidative desulfurization (ECODS) system composed of VO(acac)₂, 30% H₂O₂, and 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF₄) has been found to be suitable for the deep removal of dibenzothiophene (DBT) in model oil at room temperature. The optimal conditions were as follows: [n(H₂O₂)/n(DBT)/n(catalyst) = 100:20:1], model oil = 5 mL, ionic liquid [IL] = 1 mL, T = 30°C, t = 2 hr. With the ECODS system, the sulfur removal of DBT could reach 99.6%, which was superior to that of the simple extraction with IL (15.6%) or oxidation without catalyst (17.1%). The IL could be recycled five times without a significant decrease in activity.     

Prediction of density and viscosity of ternary systems [C_2q]Br＋[C_4q]Br＋H_2O, [C_2q]Br＋[C_6q]Br ＋H_2O, and [C_4q]Br＋[C_6q]Br＋H_2O at different temperatures using their binary subsystems data

The simple equations for prediction of the density and viscosity of mixed electrolyte solutions were extended to the related properties of mixed ionic liquid solutions. The density and viscosity were measured for ternary solutions [C2q]Br(N-ethylquinolinium bromide)+[C4q]Br (N-butylquinolinium bromide)+H2O, [C2q]Br+[C6q]Br(N-hexylquinolinium bromide)+H2O, and [C4q]Br+[C6q]Br+H2O and their binary subsystems [C2q]Br+H2O, [C4q]Br+H2O, and [C6q]Br+H2O at 15, 20 and 25 °C, respectively. The results were used to test the predictability of the extended equations. The comparison results show that these simple equations can be used to predict the density and viscosity of the mixed ionic liquid solutions from the properties of their binary subsystems of equal ionic strength.     

烷基咪唑高氯酸盐离子液体的萃取脱硫研究

以N-甲基咪唑、溴代烷烃、高氯酸钠为原料,合成烷基碳链长度不同的烷基咪唑高氯酸盐离子液体,分别考察不同条件下离子液体对模拟油品和实际油品的脱硫效果。研究结果表明,以[C6mim]ClO4离子液体为萃取剂,在萃取温度60 ℃、萃取时间50 min、离子液体与油品的体积比4:1的条件下,对硫质量分数为1 160 μg/g的模型油的一次萃取脱硫率达到86.90%;当其它条件不变,在离子液体与油品的体积比为1:1时,对硫质量分数为117 μg/g的催化裂化汽油的一次脱硫率为65.24%,对硫质量分数为1 974 μg/g的催化裂化柴油的一次脱硫率为58.05%。反应结束后,通过简单的倾倒即可将油样和离子液体分离,离子液体经减压蒸馏提纯干燥后可重复使用5次以上,其催化活性不降低。     

Remove Olefin from Diesel Oil with Chloroaluminate(III) Ionic Liquids

Abstract

Ionic liquids are low-melting-point salts that represent an exciting new class of reaction solvents. In this article, the author mainly refers to the effects of the olefin removal in the diesel oil using [bmim]Br-AlCl₃ (where [bmim] is 1-butyl-3-methylimidazolium cation) ionic liquid. The result shows the better performance in the olefin removal. Therefore, an environmental friendly approach for olefin removal from diesel is provided.     

Solubility of β-cyclodextrin in different mixed solvents

The solubility of β-cyclodextrin (β-CD) in ionic liquid/N, N-dimethyl-acetamide (IL/DMAC) mixed solvent and in LiCl/DMAC mixed solvent was investigated at 323.15 K and 353.15 K. The results showed that the solubility of β-CD in IL/DMAC system increased with increasing temperature, but decreased in LiCl/DMAC system. β-CD had the highest solubility in IL/DMAC system with [Cl]⁻ or [Br]⁻ anions. The solubility of β-CD in LiCl/DMAC system was lower than that in IL/DMAC system with [Cl]⁻ or [Br]⁻ anions but higher than that in IL/DMAC system with weak-coordinated anions (e.g [BF₄]⁻ or [PF₆]⁻). The effects of substituent groups (benzyl and butyl) of cation and the structure of cations on β-cyclodextrin solubility were also investigated.     

Optimization of Oxidative Desulfurization of Dibenzothiophene Using a Coordinated Ionic Liquid as Catalytic Solvent

Abstract

Oxidative desulfurization (ODS) of dibenzothiophene (DBT) in n-octane with hydrogen peroxide/acetic acid using a quaternary ammonium coordinated ionic liquid (IL) (C₄H₉)₄NBr · 2C₆H₁₁NO as catalytic solvent has been studied. The ODS mechanism by coordinated ionic liquid [(C₄H₉)₄NBr · 2C₆H₁₁NO] was also carried out. The sulfur-containing compounds in model oil were extracted into ionic liquid phase and oxidized to their corresponding sulfones by H₂O₂. The effect factors for desulfurization of model oil were investigated in detail by means of monofactorial and orthogonal experiments (L₁₆(4)⁴). The results showed that the desulfurization efficiency of model oil could reach 98.6% under the optimal conditions of oxidation time, oxidation temperature, molar ratio of H₂O₂/sulfur (O/S), and volume ratio of model oil to coordinated ionic liquid were 30 min, 50°C, 16, and 1, respectively. The influences to the desulfurization efficiency of DBT decreased in the following order: volume ratio of model oil to coordinated ionic liquid (C₄H₉)₄NBr · 2C₆H₁₁NO (V_{model oil}/V_IL) > molar ratio of O/S > oxidation temperature > oxidation time, according to extreme analysis of the orthogonal test. The coordinated ionic liquid (C₄H₉)₄NBr · 2C₆H₁₁NO can be recycled 5 times without a significant decrease in desulfurization.     

The Extractive Desulfurization of Fuels Using Ionic Liquids Based on FeCl3

Abstract

Six Lewis acid ionic liquids were synthesized and employed as extractants for desulfurization of the model oil containing dibenzothiophene (DBT). Very promising ionic liquid was 1-butyl-3-methylimidazolium chloride-FeCl3 ([bmim]Cl/FeCl3), which performed best in the studied ionic liquids under the same operating conditions. It can remove DBT from model oil after continuous extraction for four steps, and the desulfurization efficiency can reach 97.9% under mild reaction conditions. Other sulfur-containing compounds were also investigated. The used ionic liquid could be regenerated six times without a significant decrease in activity.     

Implementation of CPA EoS for simultaneous solubility modeling of CO2 and H2S in ionic liquid [OMIM][Tf2N]

In this study, solubility of pure CO₂ and H₂S and their mixture in [OMIM][Tf₂N] modeled applying CPA EoS. CPA combines the SRK equation with an advanced association term, which is similar to that of SAFT. From a practical point of view, the target in the CPA project was to develop a thermodynamic model capable of describing complex equilibria of mixtures containing polar/associating chemicals through a simple procedure with respect to the SAFT.

The AAD% for binary systems, including H₂S+ IL and CO₂+ IL are 6.81, 5.21 respectively. Moreover, AAD% equal to 13.89 was achieved for the ternary system.     

The CPA EoS application to model CO2 and H2S simultaneous solubility in ionic liquid [C2mim][PF6]

The CPA EoS was utilized for solubility modeling of pure CO₂ and H₂S and their mixture in [C₂MIM][PF₆]. The model is comprised of SRK EoS in addition to Wertheim's association term. Up to now, several associating models such as SAFT variants have been successfully applied to such systems. Considering the complexity and time consuming nature of SAFT EoSs, CPA can be a good alternative due to its accuracy and simplicity with respect to the SAFT.

The AAD % for binary systems including H₂S+ IL and CO₂+ IL are 11.78, 10.40 respectively. Moreover, the ternary system show AAD% equal to 16.51.     

1-丁基-3-甲基咪唑六氟磷酸盐萃取香豆素

实验采用疏水性离子液体1-丁基-3-甲基咪唑六氟磷酸盐([C_4mim][PF_6])代替挥发性有机溶剂,由水相中萃取香豆素。采用紫外分光光度法测定了香豆素质量浓度,考察了温度、pH值、相比、香豆素质量浓度、萃取时间等因素对萃取效果的影响。结果表明,在10～50℃和pH=1～11条件下,温度和pH值对萃取效果几乎无影响;当萃取时间为10 min、V(香豆素水溶液):V([C_4mim][PF_6])=3:1、香豆素质量浓度为1.0g/L时,萃取效果最好;在该条件下,以100mL[C_4mim][PF_6]为萃取剂,平均萃取率达94.55%。离子液体中的香豆素用3倍体积量的NaOH水溶液反萃取3次,可将香豆素完全转移到水相;离子液体相用蒸馏水洗至中性,80℃减压干燥5 h后可重新使用。     

BrФnsted-Lewis双酸性离子液体催化合成二苯甲烷二氨基甲酸甲酯

合成了具有不同ZnCl2摩尔分数的BrФnsted-Lewis双酸性离子液体[HO3S-(CH2)4-mim]Cl-xZnCl2,采用Hammett指示剂与紫外联用法测定了其酸强度,考察了其在苯氨基甲酸甲酯(MPC)与甲醛(HCHO)缩合制备二苯甲烷二氨基甲酸甲酯(MDC)反应中的催化性能,并考察了反应条件对MDC收率和MPC转化率的影响。结果表明,当x=0.7时该离子液体的催化活性最高。以[HO3S-(CH2)4-mim]Cl-0.7ZnCl2为催化剂兼溶剂,在反应温度70℃、反应时间60min、MPC与HCHO的摩尔比为10、离子液体与MPC的质量比为2的条件下,MDC收率最高可达99.1%。用水处理反应液并通过减压蒸馏回收的离子液体可以循环使用5次,其催化活性基本不变。     

A New Approach to Dearomatization of Gasoline by Ionic Liquid and Liquid–Liquid Extraction

Abstract

The objective of this article was the development of a separation technology for the selective recovery of the aromatic compounds such as benzene, toluene, ethylbenzene, and xylenes (BTEX) from gasoline by extraction. A liquid–liquid extraction method using ionic liquid (IL) was optimized simultaneously for some aromatic hydrocarbons in gasoline. 1-Butyl-3-methyl imidazolium tetrachloroaluminate ionic liquid or [BMIM][AlCl₄] was used to extract aromatic compounds from gasoline. [BMIM][AlCl₄] was found to be effective for the selective removal of aromatic hydrocarbons from gasoline. The dearomatization experiments were carried out with a 1:1 volume ratio of ionic liquid to gasoline for 60 min at 50°C. The aromatic hydrocarbons removal selectivity followed the order benzene > toluene > xylene > ethylbenzene.     

金属络合类离子液体用于汽油萃取脱硫的研究

本文由原料[Et₃NH]Cl、无水FeCl₃和无水CuCl合成了离子液体[Et₃NH]Cl-FeCl₃/CuCl,考察了其萃取脱硫性能。结果表明：在对模拟汽油（噻吩溶于正辛烷）和FCC汽油脱硫时,离子液体[Et₃NH]Cl-FeCl₃/CuCl均表现出了较好的脱硫性能。当离子液体和模拟汽油的体积比V(IL):V(oil)=0.08,时间t=50min,温度T=50℃时,模拟汽油中噻吩的脱除率能够达到 93.9%。在相同的温度和时间条件下,当离子液体和FCC汽油的体积比V(IL):V(oil)=0.1时,经过三次萃取,能够获得低硫（硫含量小于10μg/g）FCC汽油,FCC汽油的收率为94.3%。离子液体具有较好的循环使用能力,循环使用5次后,汽油中噻吩的脱除率没有明显降低。