N-烷基-N-甲基咪唑系列离子液体中ZSM-5分子筛催化环已烷氧化反应

Heterogeneous oxidation of cyclohexane by tert-butyl hydroperoxide (TBHP) was carried out over ZSM-5 catalysts with different Si/Al ratios in ionic liquids and organic molecular solvents. Higher yield and selectivity of the desired products were found in ionic liquids than in molecular solvents. The conversion of cyclohexane exhibits a decrease from 15.8% to 10.8% with the increase of Si/Al ratio of the HZSM-5 catalyst, and all the catalysts exhibit good selectivity of monofunctional oxidation products at around 97%. The activity of catalyst is found strongly de-pendent on the alkyl chain length of ionic liquid.     

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.     

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.     

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.     

[bupy]BF4-AlCl3离子液体上甲苯和间戊二烯的烷基化反应

The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene was carded out to obtain 2,6-dimethylnaphalene, which is an important intermediate during the production of 2,6-naphthalene dicarboxylic acid. Based on our previous work using anhydrous AlCl3 as catalyst, [bupy]BF4-AlCl3 ionic liquids were employed to catalyze the reaction of 1,3-pentadiene with toluene. The experimental results show that [bupy]BF4-AlCl3 ionic liquids are suitable for the reaction especially when the molar ratio of AlCl3 to [bupy]BF4 is 1.75 ： 1, and the reaction could proceed at the temperature as low as 0℃. It could be as active as pure AlCl3, but much more environmentally friendly.     

Supercapacitive properties of MnNiSx@Ti3C2Tx MXene positive electrode assisted by functionalized ionic liquid

MnNiS_x@Ti₃C₂T_x as the positive electrode of supercapacitor was successfully prepared by hydrothermal method with the assistance of amino-functionalized ionic liquids.The micromorphological structures of MnNiS_x@Ti₃C₂T_x were analyzed using X-ray diffraction,scanning electron microscope,X-ray photoelectron spectroscopy,transmission electron microscope,and energy dispersive spectrometer to reveal the synergistic ...     

Determination and Correlation of Solubilities of Four Novel Benzothiazolium Ionic Liquids with PF6^- in Six Alcohols

Four novel benzothiazolium ionic liquids with 6PF- （[C1Bth][PF6], [C4Bth][PF6], [C5Bth][PF6] and [C6Bth][PF6]） were synthesized, and the rang of their melting points were determined between 358.35 K-424.05 K. The relationship of their melting points and the length of the straight alkyl chain on cation reflected‘S’ type ten-dency. Then, the solubilities of the four ionic liquids in six lower alcohols （methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-methyl-1-propanol） were measured in the temperature rang of 253.15-383.15 K at at-mospheric pressure with static analytical method, respectively. It was found that [C6Bth][PF6] in all investigated ionic liquids had the largest solubility in six alcohols and the solubility of [C4Bth][PF6] in methanol was very sensi-tive for temperature in 313.15-333.15 K, which was so-called “temperature-sensitivity”. This feature is of great significance to their application of catalyzing reaction or extraction process, and makes the recovery and reuse of ionic liquids （ILs） become easier. Moreover, the experimental solubility data were correlated with the modified Apelblat equation andλh equation, respectively. It was found that the result of correlation using two divided tem-perature ranges was better than that of using the whole temperature range.     

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.     

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%.     

Application of Brönsted acid ionic liquids as green catalyst in the synthesis of 2-propanol with reactive distillation

Five Br?nsted acidic ionic liquids (ILs) were prepared and characterized by FT-IR, 1H NMR and 13C NMR. Their cat-alytic activities for the synthesis of 2-propanol (IPOH) via transesterification of isopropyl acetate (IPAc) with methanol (MeOH) were investigated. Among al the tested ILs, [Ps-mim]HSO4 performed best and was used as catalyst for further studies. The reaction kinetics were carried out to correlate the parameters in a homogeneous second order kinetic model. It has been found that there is close agreement between the calculated and experi-mental values. The high-pressure batch reactive distillation experimental apparatus was set up in order to en-hance the conversion of IPAc. A high conversion of IPAc of 99.4%was obtained under the optimal reaction conditions. The catalyst [Ps-mim]HSO4 can be recycled easily by a rotary evaporator and reused without any fur-ther treatment. The catalyst had been repeatedly used for four times and no obvious changes in the structure of catalyst could be observed.     

吡啶离子液体中氯化亚铜纳米粒子催化合成酮代紫罗兰酮

吡啶离子液体[Epy]BF_4或[Bpy]BF_4结合简单铜盐和叔丁基过氧化氢为酮代紫罗兰酮的合成提供了一种有效和环境友好的方法.生成的目标产物3-酮代-α-紫罗兰酮和4-酮代-β-紫罗的收率分别可达70%和56%,该方法的反应介质[Bpy]BF_4和催化剂氯化亚铜可回收再利用5次.     

氧代-β-紫罗兰酮的合成

在吡啶溴翁和吡啶氯翁离子液[Epy]Br、[Bpy]Br和[Bpy]Cl中,以氯化亚铜为催化剂,叔丁基过氧化氢为氧化剂,可以直接-β-紫罗兰酮选择性氧化合成4-氧代-β-紫罗兰酮,收率可达55%。该方法使用了无毒的氧化剂和催化剂,反应介质和催化剂氯化亚铜可回收再利用,因此是一种有效和环境友好的合成氧代-β紫罗兰酮的方法。     

过氧叔丁醇催化氧化法合成4-氧代-β-紫罗兰酮

开发了一种以过氧叔丁醇为氧化剂,乙酰丙酮钒为催化剂合成4-氧代-β-紫罗兰酮的方法。主要探讨了氧化剂用量、催化剂用量、溶剂、温度对反应的影响。得出4-氧代-β-紫罗兰酮的有利合成条件是β-紫罗兰酮1.92g(10mmol),VO(acac)20.13g(0.5mmol),过氧叔丁醇50mmol,在35℃下于10mL丙酮中反应6h,4-氧代-β-紫罗兰酮的产率达到68%,纯度高于98%。     

[Bmim]PF6在甲醇和乙腈中的电导率和黏度研究

测定了298.15K条件下1-丁基-3-甲基咪唑六氟磷酸盐离子液体（[Bmim]PF₆）在甲醇和乙腈中的电导率和黏度,讨论了[Bmim]PF₆/甲醇和[Bmim]PF₆/乙腈体系的溶液性质。结果表明,在0～0.3mol/L的浓度范围内,[Bmim]PF₆/甲醇和[Bmim]PF₆/乙腈体系的电导率随[Bmim]PF₆浓度的增加而增加,并且[Bmim]PF₆在甲醇中的电导率高于在乙腈中的电导率,说明[Bmim]PF₆在甲醇中更容易电离;[Bmim]PF₆/甲醇和[Bmim]PF₆/乙腈体系的摩尔电导率随浓度的增加而降低,采用Kohlrausch公式计算回归了[Bmim]PF₆在甲醇以及乙腈中的无限稀释摩尔电导率（∧_m^w）,其值分别为156.96和153.83s·cm²·mol^-1。由Jones-Dole方程计算回归了[Bmim]PF₆在甲醇和乙腈中黏度B系数,其值分别为0.36813和0.63248,表明[Bmim]PF₆在甲醇中的黏度小于在乙腈中的黏度,这与电导率实验的结果是一致的。     

离子液体对气体的溶解性研究进展

概述了不同离子液体对CO2,O2,SO2,CH4等以及烯烃和烷烃气体的溶解性。文献资料分析表明,气体在离子液体中的溶解性差别很大,离子液体中的阴离子对气体的溶解度影响较大,而阳离子的影响较小。大部分气体在离子液体中的亨利系数随温度的升高而增大。气体在[bmim][PF6]中的溶解度比在[bmim][BF4]中的稍大。低温时[bmim][PF4]离子液体对CO2气体的吸收效果较好;[hmim][Tf2N]离子液体对SO2气体的吸收较好。在将离子液体用于气体吸收时可优先考虑Tf2N^-阴离子和具有较长侧链的眯唑型离子液体。     

用NRTL方程关联和预测离子液体-醇-水体系的液液相平衡

引 言 离子液体是指在室温或室温附近温度下呈液态的由离子构成的有机熔融盐,其特点是:几乎没有蒸气压,热稳定性好,大多数离子液体可以在高达300℃的温度范围内不分解,还对大量常见的有机物或无机物有良好的溶解性能,用离子液体替代传统的有机溶剂作为反应和分离的介质,也能有效地消除VOCs污染.因此,离子液体的研制和应用受到了广泛的关注[1-3].     

甲基丙烯醛氧化酯化制甲基丙烯酸甲酯

制备了用于甲基丙烯醛(MAL)一步氧化酯化为甲基丙烯酸甲酯(MMA)的新型催化剂;考察了反应温度、催化剂在反应体系中的质量分数对MAL转化率和产物选择性的影响;将离子液体[bmim]PF6用于该反应中,不仅提高了产物的选择性,还能有效防止产物的聚合。反应温度θ=50℃,催化剂在反应体系中质量分数为2 4%,pH=10 5,O2流量6mL/min,反应时间6h时,在反应体系中添加1mL离子液体[bmim]PF6,MAL的转化率为96 2%,MMA单体的选择性可达98 7%。     

氯化1-{2-[双(2-氨基乙基)氨基]乙基}吡啶离子液体的合成及在ATRP反应中的应用

采用N-烷基化方法将二乙烯三胺（DETA）接枝到氯化1-氯乙基吡啶离子液体[CePy]Cl上,合成了离子液体氯化1-{2-[双（2-氨基乙基）氨基]乙基}吡啶（[N₃Py]Cl）,通过FTIR、¹H NMR和MS等测试手段对合成离子液体的结构进行了表征。采用循环伏安法对离子液体配合物[N₃Py]Cl/CuBr和有机配合物PMDETA/CuBr的氧化还原电位（E_1/2）进行测试,结果表明：合成的离子液体[N₃Py]Cl和CuBr形成配合物的氧化还原电势为E_1/2=-0.541V,比常用的有机配合物PMDETA/CuBr（E_1/2=-0.142V）具有更低的氧化还原电势。将离子液体[N₃Py]Cl与CuBr配位形成催化体系,在离子液体[AMIM]Cl中催化甲基丙烯酸甲酯（MMA）的原子转移自由基聚合（ATRP）反应。结果表明,当配体、催化剂和溶剂的用量分别为n（CuBr）=0.19mmol、n（[N₃Py]Cl）=1.13mmol、n（[AMIM]Cl）=0.02mol,反应温度60℃,反应时间4h时,单体转化率高达75%,分子量分布较窄（M_w/M_n=1.24）,ATRP反应具有明显的可控性能。     

离子液体[bmim]PF_6对聚乳酸的增塑作用

合成了离子液体[bmim]PF6(1-丁基-3-甲基咪唑六氟磷酸盐),并对其进行了表征。用TG、DSC和偏光显微镜等手段研究了[bmim]PF6对聚乳酸的增塑作用,并比较了它与聚乙二醇300(PEG300)的增塑效果。热重分析结果表明,PEG300作增塑剂时,由于其热降解温度较低,聚乳酸热稳定性变差;离子液体[bmim]PF6作增塑剂时,由于其热失重温度高于聚乳酸热降解温度,用其增塑的聚乳酸热稳定性变好。当[bmim]PF6的质量分数从2%增加到10%时,聚乳酸材料的玻璃化转变温度(Tg)随之降低,当加入质量分数为10%的[bmim]PF6时,聚乳酸材料的Tg降至40℃。偏光显微镜观察看出,加入[bmim]PF6后聚乳酸分子链段的活动能力增强,促进了聚乳酸的结晶,且随其用量增加,结晶度增加。该文报道工作的新颖性,已为教育部科技查新工作站(Z12)于2008年2月26日出具的第ZDT2008017号《科技查新报告》所证实。