离子液体催化的芳烃氯甲基化反应

Ionic liquids have been used as catalysts for Blanc reaction of toluene. The effects of reaction temperature, reaction time and dosage of the ionic liquid catalyst have been investigated, and the catalytic performance of different ionic liquid catalysts for toluene chloromethylation was also studied. The reaction was found to proceed under mild conditions with excellent conversion （up to 90%） in the absence of Lewis acids. The ionic liquids could be recycled and reused without loss of their catalytic activities.     

离子液体；石油沥青质的新型溶剂

The dissolution of petroleum asphaltenes with ionic liquids is studied for the first time. The results show that the ionic liquids could be used as novel solvents for asphaltenes. The important parameters governing the ability of ionic liquids for dissolution of asphaltenes are discussed. It is found that, the ionic liquids based on the cations containing a conjugated aromatic core or the anions which are strong hydrogen bond acceptors are most effective, whereas the ionic liquids containing ＇non coordinating＇ anions such as [BF4]^- and [PF6]^- are nonsolvents for asphaltenes. Increase in the effective anion charge density enhances the ability of ionic liquids to break the extensive asphaltene associations and thus enhances the solubility of asphaltenes in the ionic liquid. The dissolution ability of ionic liquid decreases apparently with increasing the substituted alkyl chain length of its cationic head ring. Temperature is found to play an important role on dissolution of asphaltenes, and the dissolution can be significantly imoroved bv microwave heatinz.     

离子液体催化丁醇与盐酸反应制备丁基氯

The catalytic performance of some quaternary ammonium salts for the liquid phase reaction of butanol and hydrochloric acid at different conditions was studied experimentally and compared with the traditional catalyst （ZnCl2）. The organic ammonium catalysts investigated include ionic liquids N-butyl-N-methyl imidazolium fluoborate （[BMIM][BF4]） and N-butyl-N-methylimidazolium chloride （[BMIM]Cl） as well as hydrochloric salts of N-methylimidazol （[HMIM]Cl）, pyridine （[HPy]Cl） and triethylamine （[HEt3N]Cl）. It is shown that the intrinsic catalytic performance of all organic ammonium salts except [HEt3N]Cl is slightly superior to ZnCl2, while the selectivity of butyl chloride is nearly at the same level around 96%. The conversion of butanol increases slightly with temperature and the catalyst amount added while the variation of selectivity is not obvious. Based on the recycle experiments, the ionic liquids as catalyst for the reaction of butanol and hydrochloric acid can be used more than 5 times, which suggests great potential of using ionic liquids as novel catalyst for such reactions.     

Conductivities of AlCl3/Ionic Liquid Systems and Their Application in Electrodeposition of Aluminium

Solubilities and conductivities of anhydrous AlCl3 in six kinds of ionic liquids (ILs) were measured. Among the six kinds of ILs [bmim]Cl, [bmim]Br, [bmim]BF4, [bmim]PF6, [emim][EtSO4] and [bmim][HSO4], anhydrous AlCl3 could be dissolved in the first five kinds but was hardly dissolved in [bmim][HSO4]. The results showed that the nominal solubilities of AlCl3 in ILs increased in the order of [bmim][HSO4] < [bmim]PF6 < [emim][EtSO4] < [bmim]BF4 < [bmim]Cl < [bmim]Br. Conductivities of the AlCl3/ILs systems depended apparently on the nominal molar ratio of AlCl3 to ILs. The conductivities of AlCl3/[bmim]Cl, AlCl3/[bmim]Br and AlCl3/[bmim]PF6 systems had a similar tendency as a function of the nominal molar ratio, that is, as the molar ratio was increased, conductivities increased first and then decreased, with the maximum conductivity obtained at approximately 0.9:1, 1.0:1 and 0.5:1, respectively. Conductivities of the AlCl3/[bmim]BF4 exhibited a dentate change and decreased with the molar ratio of AlCl3 to [bmim]BF4 increasing in general. With the increasing of the anhydrous AlCl3 amount in [emim][EtSO4], conductivity of AlCl3/[emim][EtSO4] monotonically decreased. AlCl3/[bmim]Cl system was chosen as the electrolyte for the electrodeposition of Al. Preliminary experimental results showed that dense, adherent and homogeneous Al coatings could be electrodeposited on stainless steel by means of constant potential technique and the surface coverage was quite satisfactory.     

复合离子液体催化碳酸乙烯酯水解制备乙二醇(英文)

An ionic liquid system of [Bmim]X/[Bmim]OH (X Cl, BF4, and PF6,) was developed for the hydrolysis of ethylene carbonate to ethylene glycol. The important parameters, such as the variety of ionic liquids, molar ratio of [Bmim]X to [Bmim]OH, amount of ionic liquid, molar ratio of water to ethylene carbonate, reaction temperature, pressure and reaction time, were investigated systematically. Excellent yield (>93%) and high selectivity (99.5%) of ethylene glycol were achieved. Under the optimum reaction conditions, the ionic liquid system could be reused at least five times and the selectivity of ethylene glycol remained higher than 99.5%.     

四氟硼酸盐类离子液体对典型柴油的萃取脱硫研究

The extractive removal of sulfur compounds （S-compounds） from Dongying and Liaohe diesel fuels with [BF4]^--based ionic liquids were systematically investigated. The results show that the absorption capacity of an ionic liquid for the S-compounds in diesel fuels relies on its structure and its size. In the case of the two examined diesel fuels, both elongating the cation tail length and increasing the mass ratio of ionic liquid/diesel fuel promote the desulfurization ability of the examined ionic liquids. The results also show that imidazolium-based ionic liquids display higher extraction efficiencies than pyridinium-based ionic liquids, presumably owing to the fact that the rings of the S-compounds are similar to the imidazolium head ring. With the 1 ： 1 mass ratio of ionic liquid/diesel fuel, the rates of the first desulfurization of Dongying and Liaohe diesel fuels using [C8mim][BF4] amount to 29.96% and 39.76%, suggesting that [C8mim][BF4] is a promising extractant for desulfurization of these diesel fuels.     

二氧化硫和二氧化碳在离子液体支撑液膜中的渗透率和选择性

Permeabilities and selectivities of gases such as carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen (N2) and methane (CH4) in six imidazolium-based ionic liquids ([emim][BF4], [bmim][BF4], [bmim][PF6], [hmim][BF4], [bmim][Tf2N] and [emim][CF3SO3]) supported on polyethersulfone microfiltration membranes are investigated in a single gas feed system using nitrogen as the environment and reference component at temperature from 25 to 45ºC and pressure of N2 from 100 to 400 kPa. It is found that SO2 has the highest permeability in the tested supported ionic liquid membranes, being an order of magnitude higher than that of CO2, and about 2 to 3 orders of magnitude larger than those of N2 and CH4. The observed selectivity of SO2 over the two ordinary gas components is also striking. It is shown experimentally that the dissolution and transport of gas components in the supported ionic liq-uid membranes, as well as the nature of ionic liquids play important roles in the gas permeation. A nonlinear in-crease of permeation rate with temperature and operation pressure is also observed for all sample gases. By considering the factors that influence the permeabilities and selectivities of CO2 and SO2, it is expected to develop an optimal supported ionic liquid membrane technology for the isolation of acidic gases in the near future.     

新型离子液体用于芳烃、烯烃与烷烃分离的初步研究

The separation of aromatic hydrocarbons or olefins from paraffins is very important in chemical industry. The volatile organic solvents used are usually harmful to environment and human health. As green solvents, room temperature ionic liquids are potential substitutes for the separation of hydrocarbon products. Activity coefficients at infinite dilution of hydrocarbon solutes, such as alkanes, hexenes,alkylbenzenes and styrene, in 1-butyl-3-methyl imidazolium hexafluorophosphate ( [BMIM] [PF6]), 1-allyl-3-methylimidazolium tetrafluoroborate ( [AMIM] [BF4] ), 1-isobutenyl-3-methylimidazolium tetrafluoroborate ( [MPMIM] [BF4]) and [MPMIM] [BF4] AgBF4 were determined by gas-liquid chromatography. The measurements were carried out at different temperatures between 298.15 K and 318. 15 K. The separation effects of these ionic liquids for olefin/paraffin, alkanes/benzene and hexene isomers were discussed.     

Removal of mercaptans from light oils using ionic liquid–NaOH aqueous solution as extractants

The application of ionic liquids as alternatives to conventional organic solvents in the extraction process has been investigated. In the present study, fourteen species of imidazolium-based ionic liquids were added into the Na OH(aq) to remove the mercaptans. The influences of anion species and cation alkyl chain length of the imidazolium-based ionic liquids on the performance of mercaptan removal from light oils have been discussed.The efficiency of extraction for mercaptans exhibited the order of [Ac]~-N [OH]~-≈ [Br]~-N [BF4]~-. The longer alkyl chain imidazolium-based ionic liquids contributed to enhance desulfurization rate of 1-butyl mercaptan.100% desulfurization rate of 1-butyl mercaptan was achieved by the anion of Ac-ionic liquids and Na OH(aq)at a volume ratio of 40:1(V(oil):V(ionic liquid)) and a short equilibrium time within 10 min.     

[bmim]Cl／FeCl3离子液体催化苯与乙烯烷基化反应的新型机理

Up to now the mechanism of Friedel-Crafts reactions catalyzed by ionic liquid have not been fully understood, while carbocation mechanism was assumed. It was found that the source of H and the route of reaction initiated the alkylation of benzene with ethylene catalyzed by [bmim]Cl/FeCl3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity for the alkylation of benzene with ethylene suggests that there exists a new catalytic route. The distinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of [bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shifts of proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl3 content and shifted downfield when FeCl3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to be disengaged from imidazolium ring with formation of H^ to initiate the reaction. The isotope-substituted method was employed to prove this mechanism, through the GC-MS analysis of alkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeC13 ionic liquid was found to follow the carbocation mechanism, the resource of H was presented and proved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found that the intensity of 2-H reduced 23% after reaction showing that the H arising from alkylation reaction was supplied by 2-H on the imidazole ring.     

［Emim］HSO4-AlCl3催化1-丁烯齐聚

制备Brnsted-Lewis双酸性离子液体催化剂［Emim］HSO4-AlCl3,并用于催化1-丁烯齐聚反应,考察催化剂用量、反应压力、反应温度和反应时间对1-丁烯齐聚产物选择性的影响。结果表明,强酸性离子液体催化1-丁烯齐聚反应得到的产物主要为四聚体。在n(AlCl₃)∶n(［Emim］HSO₄)=1∶1、催化剂用量2.5 g、反应温度30 ℃、反应压力0.08 MPa和反应时间1.0 h条件下进行齐聚反应,产物选择性和反应体系的稳定性较理想。     

离子液体催化1-己烯齐聚反应的研究

分别以氯化1-丁基-3-甲基咪唑和盐酸三乙胺为阳离子,氯化铝和氯化铁为阴离子合成酸性离子液体催化剂,用于1-己烯齐聚反应研究。结果表明,以［Bmim］Cl-AlCl₃制备的催化剂活性和选择性较好。较佳工艺条件为：催化剂用量为1-己烯质量的4%,n(氯化铝)∶n(咪唑)=2.5∶1,反应时间3 h,反应温度160 ℃。气相色谱分析可知,1-己烯转化率70%以上,产物主要是二聚、三聚、四聚和较少的五聚物,没有裂解产品。     

离子液体[BzMim][BF4]催化甲苯与盐酸和聚甲醛的氯甲基化反应

以1-甲基咪唑和氯化苄为原料合成中间体氯化1-苄基-3-甲基咪唑（[BzMim]Cl）,而后与氟硼酸钠交换阴离子合成了一种新的离子液体[BzMim][BF4],并考察了该离子液体催化甲苯与盐酸和聚甲醛的氯甲基化反应的催化活性和选择性。实验结果表明,[BzMim][BF4]能够催化以浓盐酸为原料的氯甲基化反应,目标产物甲基苄基氯的产率与文献报道以离子液体C12mimBr催化干燥氯化氢为原料的相仿;对同为浓盐酸原料的氯甲基化反应,其单氯甲基化选择性远高于文献报道的以离子液体[emim]BF4为催化剂的35%;当[BzMim][BF4]与甲苯的摩尔比为0.3,多聚甲醛（PF）与甲苯的摩尔比为1.3,浓盐酸与甲苯的摩尔比为7.5,80 oC下反应8 h时,目标产物甲基苄基氯的产率达到88.5%,单氯甲基化选择性高于99%。     

Ionic liquids and nanotechnology: Synthesis of WO3 nanostructures by anodization as photoelectrocatalysts

Two ionic liquids, [BMIM][BF4] and [EMIM][BF4], have been used for the first time to synthesize ordered and well-defined WO₃ nanoplates by electrochemical anodization. Different amounts of these ionic liquids have been added to the electrolytes and their influence on the morphological, structural and photoelectrocatalytic properties of the WO₃ nanoplates has been extensively studied. The resulted nanostructures, especially those synthesized in the presence of 5%–10% ionic liquids, showed excellent photoelectrocatalytic performances under irradiation, due to their better morphology, size and arrangement. These results confirm the potentiality of ionic liquids, such as [BMIM][BF4] and [EMIM][BF4], in the synthesis by anodization of high-efficiency photoelectrocatalysts, which could be used in the energy and environmental fields.     

SEPARATION OF AROMATIC AND ALIPHATIC HYDROCARBONS WITH IONIC LIQUIDS

Naphtha cracker feeds may contain 10-25 wt% aromatic compounds. Removal of these aromatic compounds from the feed to the cracker would offer several advantages: higher capacity, higher thermal efficiency, and less coke formation. In this work, we investigated the separation of toluene from heptane by extraction with ionic liquids.

Several ionic liquids are suitable for extraction of toluene from toluene/heptane mixtures. The selectivities for the aromatic/aliphatic hydrocarbon separation with all ionic liquids tested increase with decreasing aromatic content in the feed. The toluene/heptane selectivities at 10% toluene in the feed at T = 40°C and 75°C with several ionic liquids ([emim]HSO₄, [mmim] methylsulfate, [emim] ethylsulfate, [bmim]BF₄, [emim] tosylate, [mebupy]BF₄, and [mebupy] methylsulfate) are a factor of 1.5-2.5 higher than those obtained with sulfolane, which is a conventional solvent for the extraction of aromatic hydrocarbons from a mixed aromatic/aliphatic hydrocarbon stream. The three most suitable ionic liquids from the ionic liquids tested for the separation of aromatic and aliphatic hydrocarbons are [mebupy]BF₄, [mebupy]CH₃SO₄, and [bmim]BF₄ and at 75°C also [emim] tosylate. The ionic liquid [mebupy]BF₄ is selected for further testing in our extraction pilot plant.

Because ionic liquids have a negligible vapor pressure, evaporating the extracted hydrocarbons from the ionic liquid phase could achieve the recovery of the ionic liquid. A conceptual process scheme for the extraction has been set up. Preliminary calculations show that both the investment costs and the energy costs will be considerably lower with ionic liquids than with sulfolane as the solvent.     

[bmim][BF4]离子液体中PCl3催化的液相贝克曼重排

在1-丁基-3-甲基咪唑四氟硼酸盐([bmim][BF4])与甲苯组成的两相体系中,以三氯化磷(PCl3)为催化剂,实现了由环己酮肟制备己内酰胺的液相贝克曼重排反应,两相体系有利于反应控制和体系取热. 研究了环己酮肟用量、PCl3用量、反应时间和反应温度对重排效果的影响. 优化反应条件为: 2 ml [bmim][BF4], 5 ml甲苯, 0.3 ml PCl3, 5 ml 2 mol/L环己酮肟-甲苯溶液, 90oC, 反应时间10~30 min. 此时,环己酮肟转化率达98.96%,生成己内酰胺的选择性达87.30%,PCl3催化转化数达2.88. 生成的大部分己内酰胺在离子液体相.     

离子液体与芳香类高沸点有机物相平衡

采用超临界CO2萃取方法得到了高纯度的离子液体[bmim]PF6、[bmim]BF4 和[bupy]BF4。用反相键合相高效液相色谱法（HPLC）测定了三种离子液体中萘、菲、联苯、二苯并噻吩（DBT）和二苯基二硫醚在280～340K的溶解度,分别用两参数和三参数的NRTL方程关联了测得的溶解度数据。溶解度计算值与实验值的相对平均偏差在3.86～9.94％之间。显然,可以用NRTL方程描述这些固体物质与离子液体的固液相平衡。同样条件下,测定了乙苯—[bmim]PF6、十二烷基苯—[bmim]PF6 液液相平衡数据。前者的规律也可以用NRTL方程描述,两相溶解度计算值与实验值的平均偏差分别是10.20、3.37％。     

AlCl3型季铵盐离子液体的微波法合成

在微波辅助条件下,研究了氯铝酸三乙胺盐酸盐离子液体（TECIL）、氯铝酸三甲胺盐酸盐离子液体（TMCIL）的合成。此法与文献报道中离子液体合成的常规法相比,具有加热均匀、反应速度快、操作方便、产率高等特点。实验中探讨了合成这两种离子液体的反应时间、微波功率以及原料加料方式对收率的影响。通过对实验结果的比较与分析,得出微波法合成此两种离子液体的最佳工艺条件。TECIL的最佳合成工艺条件是：D方式加料,320W的微波功率,加热时间为10s＋10s＋10s×4=60s。TMCIL的最佳合成工艺条件是：D方式加料,320W的微波功率,反应时间为10s＋10s＋10s×4=60s。     

SEPARATION OF AROMATIC AND ALIPHATIC HYDROCARBONS WITH IONIC LIQUIDS

Naphtha cracker feeds may contain 10–25 wt% aromatic compounds. Removal of these aromatic compounds from the feed to the cracker would offer several advantages: higher capacity, higher thermal efficiency, and less coke formation. In this work, we investigated the separation of toluene from heptane by extraction with ionic liquids.

Several ionic liquids are suitable for extraction of toluene from toluene/heptane mixtures. The selectivities for the aromatic/aliphatic hydrocarbon separation with all ionic liquids tested increase with decreasing aromatic content in the feed. The toluene/heptane selectivities at 10% toluene in the feed at T = 40°C and 75°C with several ionic liquids ([emim]HSO₄, [mmim] methylsulfate, [emim] ethylsulfate, [bmim]BF₄, [emim] tosylate, [mebupy]BF₄, and [mebupy] methylsulfate) are a factor of 1.5–2.5 higher than those obtained with sulfolane, which is a conventional solvent for the extraction of aromatic hydrocarbons from a mixed aromatic/aliphatic hydrocarbon stream. The three most suitable ionic liquids from the ionic liquids tested for the separation of aromatic and aliphatic hydrocarbons are [mebupy]BF₄, [mebupy]CH₃SO₄, and [bmim]BF₄ and at 75°C also [emim] tosylate. The ionic liquid [mebupy]BF₄ is selected for further testing in our extraction pilot plant.

Because ionic liquids have a negligible vapor pressure, evaporating the extracted hydrocarbons from the ionic liquid phase could achieve the recovery of the ionic liquid. A conceptual process scheme for the extraction has been set up. Preliminary calculations show that both the investment costs and the energy costs will be considerably lower with ionic liquids than with sulfolane as the solvent.