[bmim]Cl/FeCl3离子液体的表征

本文利用^1HNMR、FT-IR、FAB(Fast Atom Bornbardment)、Baman光谱分析方法表征了[bmim]Cl／FeCl3离子液体,结果表明：酸性离子液体中,阴离子主要形式是FeCl4^-、Fe2Cl7^-;碱性离子液体中,阴离子主要是Gl^-、FeCl4^-,并且三者之间存在着平衡。根据分析结果及化学软件的计算,可以推断,阴离子分布在阳离子的两边,即在[bmim]平面的两边,根据能量最低原理,Gl^-与FeCl4^-或Fe2Cl7^-离子只能连接在靠近甲基一侧,此时,分子能量最低,结构最稳定。     

[EMIM]Br-FeCl2离子液体萃取脱除含硫化合物

考察了1-乙基-3-甲基咪唑溴络合氯化亚铁([EMIM]Br-FeCl2)离子液体对含有噻吩(TS)、苯并噻吩(BT)和二苯并噻吩(DBT)模拟油及FCC汽油的萃取脱硫效果。实验结果表明:在40℃条件下萃取4 h,当剂油质量比为2∶1时,噻吩的脱除率为25.6%;当剂油质量比为2∶5时,苯并噻吩的脱除率达到72.4%,二苯并噻吩的脱除率达到79.9%。按剂油质量比2∶1应用于实际汽油,单级萃取脱硫率为50.3%～54.5%,5级萃取脱硫率为89.3%～91.3%。对使用过的离子液体进行再生处理,再生后离子液体可以使用10次以上。     

室温离子液体[bmim]BeS的萃取脱硫性能

选择水溶性的离子液体[bmim]BeS作萃取剂,对模拟油品中的4种含硫有机物噻吩、2-甲基噻吩、苯并噻吩、二苯并噻吩进行了萃取,确定了适宜的萃取操作条件。实验结果表明,[bmin]BeS对含硫化合物的萃取平衡时间只需3 min;适宜的操作温度为40～50℃。在室温下以溶剂比为1∶1对模拟体系进行4级错流萃取,脱硫率可以达到60%～90%。     

[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.     

用离子液体FeCl3-[bmim]Cl脱除汽油中硫化物的研究

在合成离子液体FeCl3-[bmim]Cl的基础上,考察了摩尔比、离子液体加入量、脱硫时间以及脱硫温度对汽油脱硫效果的影响.实验结果表明,FeCl3与[bmim]Cl的摩尔比为2:1,加入量10%,反应时间35min,温度25℃时脱硫效果最好,脱硫率达到81.5%,汽油收率达到了92.5%.     

[bmin]Cl/[FeCl3]离子液体催化的苯与1-十八烯烷基化反应

Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB （linear alkylbenzenes） was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene.     

酸性离子液体[Hnmp]HSO_4在模拟汽油脱硫中的应用研究

制备了酸性离子液体N-甲基吡咯烷酮硫酸氢盐[Hnmp]HSO_4,以其同时作为催化剂和萃取剂,H_2O_2作为氧化剂,用于氧化萃取脱除模拟汽油中硫化物的研究,采用单因素实验,优化了模拟汽油脱硫的工艺条件。研究表明,当氧化剂H_2O_2的用量为n(H_2O_2)/n(S)=6,反应时间为60 min,反应温度为50℃,离子液体用量为V([Hnmp]HSO_4):V(模拟汽油)=0.3时,模拟汽油的脱硫率可达98.5%。离子液体[Hnmp]HSO_4回收重复使用6次后,脱硫率无明显降低。     

用离子液体FeCl2-[bmim]Cl脱除汽油中硫化物的研究

在合成离子液体FeCl3-[bmim]Cl的基础上,考察了摩尔比、离子液体加入量、脱硫时间以及脱硫温度对汽油脱硫效果的影响。实验结果表明,FeCl3与[-bmim]Cl的摩尔比为2：1,加入量10％,反应时间35min,温度25℃时脱硫效果最好,脱硫率达到81．5％,汽油收率达到了92．5％。     

[omim]BF4离子液体萃取酚类化合物的研究

采用水浴微波法合成离子液体萃取剂[omim]BF4.研究[omim]BF4对苯酚、邻甲酚等7种酚类化合物的萃取,考察了萃取时间、温度、相比及pH值对萃取效果的影响.实验结果表明:萃取10 min就可以达到平衡;随着温度升高或[omim]BF4与含酚水溶液相比的降低,分配系数降低;酚溶液在pH< pKa时,即酚类化合物主要以分子状态存在时,萃取效率较高.与萃取剂[bmim]PF6及传统有机溶剂相比,[omim]BF4萃取酚类化合物的分配系数处在同一数量级.同时对[omim]BF4萃取酚类化合物的机理进行了探讨,离子液体中的氟与酚类化合物的羟基形成了氢键.     

离子液体中3,4-二羟基苯甲醛的简便合成

研究了对羟基苯甲醛在离子液体中经溴化、水解一锅法合成3,4-二羟基苯甲醛的简便方法.对羟基苯甲醛首先与离子液体[bmim]Br3进行溴化反应得到3-溴-4-羟基苯甲醛,在对羟基苯甲醛与[bmim]Br3物质的量比1:1,20℃,30min和无溶剂条件下,单溴化产物的选择性为99.7%.溴化反应产物不经分离,直接在离子液...     

离子液体用于燃油萃取脱硫的选择与过程优化

针对基于COSMO-SAC模型分子设计方法的准确性问题,采用离子液体脱硫机理分析和实验的方法对其进行了验证,即对[HMIM] [BF₄]、[HMIM] [PF₆]、[BMIM] [BF₄]、[BMIM] [PF₆]、[EMIM] [BF₄]、[EMIM] [PF₆] 6种离子液体作萃取剂时的脱硫效果进行了脱硫机理的分析和实验的验证,得到的脱硫性能排序与离子液体分子设计结果基本一致,且均认为[HMIM] [PF₆]脱硫率较高。以[HMIM] [PF₆]为萃取剂,通过液相色谱法测定萃取后的液相组成,考察萃取时间、萃取温度、剂油比3个因素对脱硫率、分配系数和选择性系数的影响。通过正交实验设计确定了萃取时间40 min、萃取温度20℃、剂油比2：1为较优操作条件,单次脱硫率为72.74%,四级萃取可将模型油的含硫量由1200 μg·g^-1降至6.98 μg·g^-1,符合国Ⅴ标准。     

[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.     

New Alkylation Route of Benzene with Ethylene Catalyzed by [bmim]Cl/FeCl_3 Ionic Liquid

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     

Distribution,Rate of Extraction,and Complexing Action of ThenoyItrifluoroacetone in the Synergistic System Kerosine/ThenoyItrifluoroacetone/Tributylphosphate/Dilute HNO3

Abstract

A study of the variation of the distribution coefficients of thenoyltrifluoro-tone (HTTA) and Sm with time has been made in the synergistic system kerosine/HTTA/tributylphosphate (TBP)/dilute HNO₃. The results indicate that the phenomena of antagonism or antisynergism which takes place at TBP concentrations above 0.1 M is due to the large reduction of the free HTTA-enol in the organic phase and to a much lesser extent to the reduction of the free TBP concentration in the same phase through the formation of HTTA-H₂O and HTTA-H₂O-TBP, respectively. Equations which allow calculation of the free HTTA-enol and free TBP are developed.