Brφnsted酸性离子液体在萃取氧化二苯并噻吩中的应用

以具有Bronsted酸性的吡咯烷酮离子液体N-甲基-2-吡咯烷酮氟硼酸盐([Hnmp]BF,)为萃取剂和催化剂,含30%质量分数H2O2的双氧水为氧化剂,二苯并噻吩(DBT)的正辛烷溶液作为模型油,同时进行萃取脱硫和氧化脱硫,考察了n(H2O2)/n(S)、DBT初始浓度和反应温度对脱硫率的影响.结果表明,[Hnmp]BF4-H2O2体系产生的羟基自由基能将DBT氧化成相应的砜而进入离子液体相,从而脱除了模型油中的S;当n(H2O2)/n(S)=3、反应温度为60℃、模型油与离子液体等体积时,在60 min内可以将油相中S质量浓度为1550 μg/ml的DBT完全氧化脱除;DBT初始浓度越高,S的完全脱除就越困难.离子液体重复再生使用7次后,脱硫率明显降低.     

氨基酸离子液体氧化-萃取脱硫工艺研究

以L-脯氨酸和浓硫酸为原料采用一步法合成出氨基酸离子液体.以所合成的离子液体为萃取剂和催化剂,30％（质量分数）的H2O2为氧化剂,对模拟油进行氧化-萃取脱硫研究.结果表明,在模拟油用量为10 mL,剂油比（离子液体与模拟油的体积比）为0.2,H2O2用量为0.2 mL,反应温度为70℃,反应时间为90 min的优选条件下,脱硫率达到97％.将脱硫后分离出的离子液体经旋转蒸发仪再生处理,循环使用5次后脱硫率仍达81％.     

新型离子液体对苯并噻吩、二苯并噻吩的萃取性能研究

离子液体是一种优良的绿色溶剂，可应用在石油油品脱硫工艺中，以降低燃油对环境的污染。本文合成了五种新型离子液体[bmim]AlCl4, [bmin]TBP, [bmim]BeS, [bmim]PF6, [bmim]BF4，并将他们用于油品脱硫的模拟体系。比较了五种离子液体萃取性能，结合分子间作用力的理论和价键理论阐述了离子液体萃取脱硫的机理。结果表明，离子液体的萃取性能与其阴离子结构有关，其中[bmim]TBP适宜作萃取脱硫溶剂。苯并噻吩(BT)、二苯并噻吩(DBT)在模拟油品中的初始浓度分别为1000μg/g时，用[bmim]TBP经四级错流萃取和5级逆流萃取，含硫量均能降至50μg/g以下。     

离子液体的萃取脱硫性能研究

 采用不同性质的离子液体萃取脱除模拟油中的有机含硫化合物。以二苯并噻吩(DBT)和萘的正己烷溶液为模型柴油考察了离子液体的饱和萃取量和选择性。结果表明，离子液体萃取脱硫可以在10min内达到萃取平衡；随着离子液体与油相体积比增大脱硫效果明显改善；离子液体中的阳离子和阴离子对脱硫效果影响很大，疏水性离子液体BMIMPF6对硫化物的萃取量远远大于亲水性离子液体BMIMBF4的萃取量；离子液体与油相体积比为1：1时，BMIMPF6和BMIMBF4萃取柴油中的硫化物，硫含量可以从530ppm分别下降到290ppm和410ppm。     

氧气氧化脱除模拟柴油中的二苯并噻吩

The potential of carrying out oxidative desulfurization (ODS) using oxygen as an oxidant was explored in this work. Octane firstly reacted with oxygen to produce hydroperoxides in-situ, which were then used as oxidants to oxidize the dibenzothiophene (DBT) in the absence of catalysts. The hydroperoxides generated in-situ were effective in oxidizing DBT to its corresponding dibenzothiophene sulfone (DBTO2) which was characterized by FT-IR and H1-NMR. The removal of DBT can reached to 98.4% at 140 °C, 4 h, oxygen partial pressure 0.4 MPa. The influences of different hydrocarbon components in diesel oil on DBT removal were investigated. The results showed that cyclohexane and n-dodecane had no effect on the removal of DBT, but the xylene had a slight negative effect on DBT removal. The possible oxidation mechanism was proposed and the concentration of hydroperoxides in both O2-oxidized octane and model diesel oil were detected.     

负载型离子液体在氧化脱硫中的应用进展

离子液体是一类新兴的绿色溶剂和催化剂,负载型离子液体可同时表现出离子液体和载体材料的优点,如较高的催化活性和较大的比表面积,因此成为研究热点。将离子液体负载到载体上可大大降低离子液体的用量并提高利用率,将其应用于燃油脱硫过程中可提高离子液体的氧化活性。笔者综述了负载型离子液体的制备方法,并介绍了负载型Lewis酸离子液体、负载型Br?nsted酸离子液体、负载型多金属氧酸盐离子液体作为催化剂进行燃油催化氧化脱硫性能的研究进展。部分负载型离子液体需加入中性离子液体或有机溶剂作萃取剂才能发挥催化作用,或吸附硫化物并将其催化氧化为砜类物质,达到深度脱硫的目的。     

SiO_2负载磷钼酸铵液相催化氧化二苯并噻吩

以正硅酸乙酯为硅源,采用溶胶-凝胶法制备了不同负载量的SiO2负载磷钼酸铵(AMPA)催化剂(AMPA/SiO2);利用XRD,FTIR,SEM等手段对AMPA/SiO2催化剂进行了表征;并以二苯并噻吩等含硫化合物为底物、以30%(w)H2O2为氧化剂,初步评价了AMPA/SiO2催化剂催化氧化噻吩类化合物的性能。实验结果表明,溶胶-凝胶法制备的AMPA/SiO2催化剂保持了磷钼酸铵的Keggin结构;含有AMPA/SiO2催化剂、30%H2O2(w)的正己烷/乙酸的双液相氧化体系可高效地将噻吩类化合物氧化为相应的砜,噻吩类化合物氧化反应活性的高低顺序为:4,6-二甲基二苯并噻吩>二苯并噻吩>苯并噻吩>噻吩;在MoO3质量分数为10%的AMPA/SiO2催化剂用量0.20 g、H2O2与二苯并噻吩摩尔比2∶1、反应温度50℃、反应时间30 min的优化条件下,二苯并噻吩砜的收率达94%,AMPA/SiO2催化剂可多次重复使用。     

Keggin结构磷钼酸及其钠盐催化的二苯并噻吩氧化脱硫反应

 以二苯并噻吩（DBT）为模型化合物和油溶性过氧化氢异丙苯（CHP）作氧化剂，考察了Keggin结构的磷钼酸（H₃PMo₁₂O₄₀）及其钠盐（Na₃PMo₁₂O₄₀）的氧化脱硫性能，并与硅钼酸（H₄SiMo₁₂O₄₀）及磷钨酸（H₃PW₁₂O₄₀）氧化脱硫性能进行对比。结果表明，H₃PMo₁₂O₄₀/SiO₂氧化脱硫活性远高于H₄SiMo₁₂O₄₀/SiO₂，而H₃PMo₁₂O₄₀/SiO₂则基本没有活性。SiO₂担载的磷钼酸及其钠盐催化DBT氧化脱硫反应活性与非负载型催化剂相比有了明显的提高。非负载型磷钼酸及其钠盐以及H₃PMo₁₂O₄₀/SiO₂在催化DBT氧化脱硫反应中都表现出一定的活性诱导期，而Na₃PMo₁₂O₄₀/SiO₂则因其较高的反应活性和CHP有效利用率，并且没有明显诱导期，在DBT氧化脱硫反应中表现出良好的催化性能。     

磷钼杂多酸离子液体在FCC汽油催化氧化脱硫中的应用

合成了一种磷钼杂多酸离子液体[HMIM]3PMo12O40催化剂,将其用于FCC汽油催化氧化脱硫过程,考察了催化氧化时间、H2O2用量、催化剂用量及反应温度对模拟汽油脱硫率的影响;在最佳工艺条件下,考察了该催化剂对FCC汽油的脱硫效果。结果表明：当催化氧化时间为90 min、反应温度为60 ℃、n(催化剂)/n(S)=0.04、n(H2O2)/n(S)=4时,模拟汽油脱硫率可达91.6%;FCC汽油的脱硫率为87.8%,且催化剂有较好的循环使用性能,前4次循环使用的平均脱硫率为84.9%。     

离子液体在烯烃环氧化反应中的应用

研究了1-辛烯、环辛烯等多种烯烃的环氧化反应,考察了反应温度、反应时间、催化体系循环使用次数等因素对环氧化反应的影响。结果表明,在离子液体1-甲基-3-丙酸咪唑硫酸氢盐中,以H2O2质量分数为30%的双氧水溶液为氧化剂,以[[(phens)2(H2O)FeⅢ]2(μ-O)](ClO4)4为催化剂,在反应温度为5℃,反应时间为15 min的最佳工艺条件下,1-辛烯转化率可达99%;催化活性随催化体系循环使用次数的增加而逐渐下降。     

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.     

Desulfurization of model FCC gasoline by extraction with ionic liquid and conventional extraction solvents

To compare the desulfurization performance of conventional extraction solvents and novel ionic liquid, desulfurization experiments by extraction were conducted on sulfolane, acetonitrile, N-formyl morpholine, and [BPy]BF₄ using model Fluid Catalytic Cracking gasoline (thiophene and n-octane) as feedstock. Results showed that the desulfurization rate of ionic liquid was worse than conventional extraction solvents, but its yield of sweet gasoline was higher, which could reach to 90.36%. Among the four solvents, N-formyl morpholine had the best desulfurization performance, while sulfolane was the most stable extraction agent.     

Synthesis and self-association of dibenzothiophene derivatives for simulation of hydrogen bonding interaction in asphaltenes

The dibenzothiophene derivatives, namely2-(dibenzothiophene-2-carbonyl)benzoic acid and 2-(dibenzothiophene-2-carbonyl)alkyl benzoate, were synthesized and characterized by nuclear magnetic resonance(1H NMR), matrix-assisted laser desorption/ionization time of flight mass spectrometry, and elemental analysis. The selfassociation behavior of these dibenzothiophene derivatives in CH2Cl2 and CH3CN was investigated using UV–visible absorption spectroscopy, fourier transform infrared spectroscopy, and atomic force microscopy. It was found that the carboxylic acid exhibited a strong self-association trend in CH2Cl2 solution at a concentration of about 5 910-7M. Hydrogen bonding of carboxyl in the dibenzothiophene derivatives was confirmed to be the main driving force for the formation of the carboxylic acid aggregates.     

WO3/C复合物的制备及其在燃料油中氧化脱硫应用

通过在520℃煅烧氧化物和氮化碳的混合物成功的合成WO3/C复合物。自制的样品通过XRD、EDS、SEM、IR和BET表征。与氧化钨和氮化碳相比较,WO3/C复合物展现出小的粒径,大的比表面积和高的脱硫活性。反应温度、催化剂用量、反应时间、氧化剂用量、硫化物类型和萃取剂用量对脱硫的影响都被研究。实验结果表明WO3/C复合物展现出比氧化钨高的脱硫活性。在催化剂用量为0.02 g,双氧水用量为0.2 mL, 1-丁基-3甲基咪唑硫酸酯用量为1.0 mL,反应温度为70 ℃,反应时间为180 min的最佳条件下,WO3/C复合物的脱硫率可达95.8%。催化剂循环使用5次,其脱硫活性没有明显的降低。     

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.     

[bmim]OH和[A336][FeCl_4]混合离子液体氧化吸收硫化氢

为了降低非水相催化氧化硫化氢体系的运行成本,将碱性的氢氧化1-丁基-3-甲基咪唑([bmim]OH)离子液体与价格较低的酸性三辛基甲基铵四氯铁酸盐([A336][FeCl_4])离子液体分别按照0.2∶1、0.5∶1、0.8∶1、1∶1和2∶1的比例混合,用所得到的混合离子液体进行硫化氢氧化吸收实验,系统研究了混合离子液体的水溶性、密度、红外光谱、黏度和酸性强度等性能,并对其硫容和反应产物进行了分析。研究结果表明:(1)[A336]FeCl_4季铵盐离子液体的酸性强度和价格均低于[bmim]Fe Cl4离子液体,可以降低离子液体非水相催化氧化硫化氢体系的成本;(2)混合离子液体不仅同时具有[bmim]OH和[A336][FeCl_4]的骨架结构,且其p H值、黏度和硫容均随[bmim]OH量的增加而增加;(3)混合离子液体明显弱于[A336][FeCl_4]离子液体的酸性强度,有利于硫化氢的吸收,其黏度随温度上升而剧烈下降的性质有利于中、高温脱硫。结论认为,当[bmim]OH/[A336][FeCl_4]的物质的量之比在0.5∶1~1∶1时,可以构建成本较低、酸性适中、黏度较低、硫容较高的中、高温脱硫体系。     

复配型铁基离子液体氧化脱除H2S动力学研究

在自建的小型实验室脱硫装置,实验筛选出了最优的弱碱性物理吸附溶剂N-甲基吡咯烷酮(NMP),然后与铁基离子液体(Fe-IL)组成脱硫复配系统。在静态高压反应釜内,研究了Fe-IL复配体系对H2S脱除性能,建立相应H2S氧化反应动力学模型。结果表明:Fe-IL/NMP复配体系脱硫后溶液增重是纯Fe-IL的4.3倍;复配体系对H2S的吸收为快速拟一级反应,脱硫过程主要受液膜控制,提高温度及NMP的复配比,可强化对H2S的吸收;通过温度、压力、溶液复配比对吸收速率的影响实验,确定了脱硫反应指前因子A为21.26,活化能Ea为12.19kJ/mol;利用化学动力学模型,最终建立了相关化学吸收速率方程。     

Catalysed oxidation of quinoline in model fuel and the selective extraction of quinoline-N-oxide with imidazoline-based ionic liquids

Synthesised vanadium-coordinated N,N-bis(o-hydroxybenzaldehyde)phenylene diamine catalyst, [VO(sal-HBPD)] and supported catalyst, p[VO(sal-HBPD)] were employed for the oxidation of quinoline. The use of [VO(sal-HBPD)] and p[VO(sal-HBPD)] for the oxidation of quinoline, (Quinoline-to-H₂O₂ ratio 1:7) showed oxidation selectivity as quinoline-N-oxide (100%) was recorded as the oxidation product. Quinoline-N-oxide was confirmed as the oxidation product through GC–MS. Density functional theory (DFT) revealed hydroxylperoxido-species [VOO(sal-HBPD)] (II) as the reactive oxidized oxidovanadium specie responsible for the oxidation. Ionic liquids, 1-butyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium nitrate extracted 96% and 87% quinoline-N-oxide respectively.