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1.
合成了一系列功能化酸性离子液体并用于模拟油品中非碱性氮-吲哚的脱除。结果表明,离子液体的阴离子对脱氮率有较大影响,离子液体的酸性越强,对吲哚的选择性脱除效果越好,不同阴离子的脱氮率顺序为:HSO4-CF3COO-H2PO4-CH3COO-。以(CH3CH2)3N(CH2)3SO3HHSO4为例,考察了剂油比、剂水比、沉降时间、反应时间和温度对油品脱氮率的影响。结果表明,在优化的工艺路线下,(CH3CH2)3N(CH2)3SO3HHSO4对油品中的吲哚脱除率可达99.12%,重复使用六次后,脱氮活性未见明显降低,具有良好的稳定性,。  相似文献   

2.
采用密度泛函理论(DFT)计算了MgAl-LDHs层板与无机阴离子(F-、Cl-、NO3-、CO32-、SO42-)和有机阴离子(水杨酸根离子([HO(C6H4)COO]-)、苯甲酸根离子([(C6H5)COO]-)、对二甲氨基苯甲酸根离子([p-(CH3)2N(C6H4)COO]-)、十二烷基磺酸根离子[C12H25SO3]-、己烷基磺酸根离子[C6H13SO3]-、丙烷基磺酸根离子[C3H7SO3]-)间的相互作用,获得稳定超分子几何结构及相互作用能。层板主体与客体间存在较强的超分子作用,包括主客体间静电作用和氢键等。主、客体间相互作用能数值大小顺序为CO32- > SO42- > F-> Cl-> NO3-;[p-(CH3)2N(C6H4)COO]-> [(C6H5)COO]-> [HO(C6H4)COO]-和[C12H25SO3]-> [C6H13SO3]- > [C3H7SO3]-。另外,还采用自然键轨道(NBO)计算和分析了LDHs 层板与阴离子间作用机理,从二阶微扰理论计算得到的稳定化能变化趋势与相互作用能数据基本吻合。  相似文献   

3.
研究了以1-丁基-3-甲基咪唑、四乙基铵及N-乙基吡啶为阳离子, 配以多种阴离子(H2PO4-, ClO4-, HSO4-, CH3COO-, Cl-, Br-, NO3-, SCN-, BF4-, PF6-)的离子液体对木瓜蛋白酶催化N-苯甲酰-L-精氨酸乙酯(BAEE)水解的活性及热稳定性的影响. 通过分析含离子液体体系中木瓜蛋白酶的水解活性和热力学失活参数, 发现该酶活性及稳定性与离子液体的Kosmotropicity性质无关. 因此, 离子的Hofmeister效应并不适合解释离子液体对木瓜蛋白酶催化特性的影响规律. 当以BF4-为阴离子, 改变阳离子结构时, 仅[BMIm][BF4]可提高酶活性, 其它含官能团的咪唑类离子液体则降低酶活性, 但大部分离子液体明显提高木瓜蛋白酶的热稳定性. 在所研究的离子液体中, 基于PF6-或BF4-阴离子的离子液体可提高木瓜蛋白酶的活性及其热稳定性. 在含[BMIm][PF6]介质中, 木瓜蛋白酶的水解活性最高; 在含[HOEtMIm][BF4]介质中其热稳定性最好.  相似文献   

4.
设计并合成了含脲苯并咪唑离子液体受体分子1~3, 利用紫外-可见光谱、 荧光光谱和 1H NMR滴定研究了其对F-, Cl-, Br-, I-, CH3COO-, HSO4-, H2PO4-等阴离子的识别性能. 紫外-可见光谱研究发现, 受体分子1~3可选择性地识别F-, 并形成1: 1型主客体配合物; 荧光光谱研究发现, 受体分子1~3对碱性阴离子有较好的识别作用, 主客体结合常数的顺序为H2PO4->CH3COO-≈ F->HSO4- ≈ Cl->Br- ≈ I-; 1H NMR滴定研究发现, 该类受体分子以咪唑2位CH和脲基NH与阴离子通过氢键结合, 但高浓度的F-会导致受体分子发生脱质子作用.  相似文献   

5.
韩富  张高勇 《化学学报》2004,62(7):733-737
含有双胺基的三硅氧烷中的伯胺基与D-葡萄糖酸-δ-内酯进行酰胺化,仲胺基与低聚乙二醇甲醚缩水甘油醚、二缩水甘油醚进行烷基化,制备了新型含硅表面活性剂Me3SiOSiMeR1OSiMe3 [R1=(CH2)3NR2(CH2)2NHCO(CHOH)4CH2OH; R2=H, CH2CH(OH)CH2O(CH2CH2O)xCH3, x=1, 2, 3] (1a, 2a~2c)和(CH2OCH2)y(Me3SiOSiMeR3OSiMe3)2 [R3=(CH2)3NR4~(CH2)2NHCO(CHOH)4CH2OH; R4=CH2CH(OH)CH2OCH2, y=0, 1, 2] (3a~3c).这些化合物的结构用1H, 13C核磁共振仪和元素分析仪进行鉴定.研究了这些新型含硅表面活性剂的界面性能,在浓度分别为10-4和10-5 mol·L-1时可以将水的表面张力降低至约21 mN·m-1.  相似文献   

6.
本文通过BnHn2-(n=10,12)及B3H8-盐分别与C5H5FeC5H4CH2N(R)Me2Cl和Fe(C5H4CH2N(R)Me2Cl)2(R=CH3-,C2H5-,n-C3H7-,CH2=CH-CH2-和CH≡C-CH2-)在水溶液中进行反应,合成了相应的三十个新的硼烷阴离子衍生物,这些化合物对水稳定性好,B10H102-及B12H122-衍生物对热、酸、碱和氧化剂均很稳定。研究了反应物之间的用量比例对反应产物的影响。实验结果表明,不论反应物之间的克分子比如何变化,只能得到相应的一种产物(产率90-98%)。  相似文献   

7.
本文报导了C5H5FeC5H4CH2N(CH3)3B3H8化合物的晶体结构,讨论了二个戊二烯环遮盖的原因。  相似文献   

8.
采用密度泛函理论(DFT), 选择杂化密度泛函TPSSh和TZVP基组, 对一个UO2(CO3)34-负离子的结构进行优化, 理论计算所得结果(键长等参数)与实验数据一致. 应用TPSSh/TZVP(ECP)方法对醋酸铀酰负离子UO2(CH3COO)3-的气相分解反应进行了理论计算, 成功地解释了含+5价铀的气相自由基负离子的稳定性, 并对2个负离子(CH3COO)UO2CH3-和CH3UO2OH-分别与水的复分解反应进行了理论计算, 所得数据与质谱的实验结果较好地吻合.  相似文献   

9.
用表面张力及电动势法研究了C10H21N(CH3)3Br、C12H25N(CH3)3Br与C3F7CH2OH混合水溶液的表面与胶团性质。结果表明,对于阳离子表面活性剂,C3F7CH2OH的加入一方面增加表面活性,另一方面降低胶团反离子结合度。后者不同于阴离子表面活性剂/C3F7CH2OH混合体系,可归因于C3F7CH2OH略有酸性,因而具备一些类似阴离子表面活性剂的性质。  相似文献   

10.
设计合成了一种基于酚羟基和氨基的酰腙类探针分子, 利用紫外-可见吸收光谱和核磁滴定考察了其对F-, Cl-, Br-, I-, CH3COO-, H2PO4-, HSO4-, ClO4-, CN-, SCN-, SO2-4和NO-3等阴离子的识别作用. 结果表明, 当加入CN-离子时主体溶液颜色由无色变为黄色, 而加入其它离子时主体溶液颜色不变, 说明该探针在DMSO/H2O(体积比5: 5)体系中能选择性裸眼比色检测CN-. 核磁滴定及质谱数据表明, 该探针与CN-以1:1化学计量比结合, 该过程通过亲核加成方式完成.  相似文献   

11.
A convenient and efficient method for the synthesis of pyrazolo[3,4‐d]pyrimidin‐4‐ones via heterocyclization reaction of 5‐amino‐1H‐pyrazole‐4‐carboxamides with triethyl orthoesters using two Br?nsted‐acidic ionic liquids, 3‐methyl‐1‐(4‐sulfonic acid)butylimidazolium hydrogen sulfate [MIM+(CH2)4SO3H][HSO4?] or N‐(4‐sulfonic acid)butyl triethylammonium hydrogen sulfate [Et3N+(CH2)4SO3H][HSO4?], as efficient homogeneous catalysts under solvent‐free conditions is described.  相似文献   

12.
Distribution constants, KD, for 8-hydroxyquinolinium-anion pairs and for a series of inorganic and organic anions are reported between aqueous acidic phases and 1-butanol and 3-methyl-1-butanol. As expected, KD values are larger for anions with relatively large crystal radius (e.g., Cl- < I- < R-SO3-), smaller for anions containing either hydroxyl or carboxyl groups favoring solvation by water (e.g., HSO4-, HSeO3-, H2PO4-, C6H5COO-, CH3COO-) and larger in solvents with larger solubility parameters (e.g., 4-methyl-2-pentanone < 3-methyl-1-butanol < 1-butanol). Distribution constants between aqueous solutions and 8-hydroxyquinoline immobilized (chemically) on controlled-pore glass are estimated for a series of aromatic and aliphatic sulfonates. Aromatic sulfonates show substantially larger KD values than aliphatic sulfonates. Batch equilibration data were used to design chromatographic (liquid-solid) separation of a few sulfonates.  相似文献   

13.
高国华  张利锋  王滨燊 《催化学报》2013,34(6):1187-1191
报道了咪唑类离子液体催化吲哚和环状碳酸酯反应合成羟烷基吲哚,系统考察了反应时间、催化剂用量、反应温度和反应物比例对离子液体催化反应性能的影响.在优化的反应条件下,吲哚与碳酸乙烯酯或碳酸丙烯酯反应可高效地生成1-(2-羟乙基)吲哚、1-(2-羟丙基)吲哚及其相应的衍生物.离子液体的催化活性与离子液体中的阴离子有关,其催化活性顺序为BF4-﹤Br-﹤Cl-﹤OAc-,与阴离子的碱度顺序一致.  相似文献   

14.
We show that fingerprints of the different states of water association can be clearly distinguished in the range of the first overtone of water′s symmetric O‐H stretching in the spectra of water‐saturated [EMIm]+‐based ionic liquids with anions of substantially different hydrophilicity, such as hydrophobic [(CF3SO2)2N]?, moderately hydrophilic [CF3SO3]?, and highly hydrophilic [HSO4]?.  相似文献   

15.
Easily synthesized aldoximes have been converted to the corresponding nitriles under very mild conditions by a simple reaction using two halogen‐free SO3H‐functionalized ionic liquids, 3‐methyl‐1‐(4‐sulfonic acid)butylimi‐ dazolium hydrogen sulfate [MIM(CH2)4SO3H][HSO4] and 1‐(4‐sulfonic acid)butylpyridinium hydrogen sulfate [PY(CH2)4SO3H][HSO4], as catalyst and reaction medium without any additional organic solvent. The method was equally effective for aromatic aldoximes bearing electron‐donating and electron‐withdrawing substituents. Taking into account environmental and economical consideration, the protocol presented here has the merits of environmentally friendly, simple operation, easy work‐up and very good yields. The catalysts could be recycled and reused for several times without noticeably decreasing in their catalytic activities.  相似文献   

16.
The effect of different anions within the ionic liquid in the characteristics of solid polymer electrolytes (SPEs) based on P(VDF‐TrFE) has been investigated. 1‐ethyl‐3‐methylimidazolium acetate, [C2mim][OAc], 1‐ethyl‐3‐methylimidazolium triflate, [C2mim][(CF3SO3)], 1‐ethyl‐3‐methylimidazolium lactate, [C2mim][Lactate], 1‐ethyl‐3‐methylimidazolium thiocyanate, [C2mim][SNC] and 1‐ethyl‐3‐methylimidazolium hydrogen sulfate [C2mim][HSO4] have been used in SPE prepared by solvent casting. The polymer phase, thermal and electrochemical properties of the SPE have been determined. The thermal and electrical properties of the SPEs strongly depend on the selected IL, as determined by their different interactions with the polymer matrix. The room temperature ionic conductivity increases in the following way for the different anions: [SNC]>[CF3SO3)]>[HSO4]>[Lactate]>[OAc], which is mainly dependent on the viscosity of the ionic liquid.  相似文献   

17.
Synthesis and Structure of Hydrogen Sulfates of the Type M(HSO4)(H2SO4) (M = Rb, Cs and NH4) From the binary systems M2SO4/H2SO4 (M = Rb, Cs, NH4), three new hydrogen sulfates of the type M(HSO4)(H2SO4) could be synthesized and structural characterized. The rubidium and caesium compounds are isotypic whereas NH4(HSO4)(H2SO4) is topologically very similar to both. All three compounds crystallize with nearly identical cell parameters [Rb: a = 7.382(1), b = 12.440(2), c = 7.861(2), β = 93.03(3); Cs: a = 7.604(1), b = 12.689(2), c = 8.092(2), β = 92.44(3); NH4: a = 7.521(3), b = 12.541(5), c = 7.749(3), β = 92.74(3)], in the monoclinic space group P21/c, There exist two kinds of SO4-tetrahedra: HSO4? anions (S1) and H2SO4-molecules (S2). The HSO4? anions form hydrogen bridged zigzag chains. In the case of the Rb and Cs compounds, the H2SO4 molecules connect these chains forming double layers. The metal atoms are coordinated by 9 O-atoms with M? O-distances of 2.97 – 3.39 Å (Rb) and 3.13 – 3.51 Å (Cs). In the ammonium compound additional hydrogen bonds are formed originating from the NH4+ cation. This finally leads to the formation of S2? NH4+ chains (parallel to the S1 chains) as well as to a three-dimensional connection of both kinds of chains.  相似文献   

18.
Thermal decomposition onset temperatures have been measured for a total of 24 methylimidazolium, triethanolammonium, and pyridinium type sulfonic acid groups functionalized Brönsted acidic ionic liquids with Cl?, Br?, SO4 2?, PO4 3?, BF4 ? , CH3CO2 ?, and CH3SO3 ? anions, using thermogravimetric analysis. Thermal stabilities of these sulfonic acid group functionalized ionic liquids decreases in the order, methylimidazolium > triethanolammonium > pyridinium. The methylimidazolium, pyridinium, and triethanolammonium ionic liquids investigated showed decomposition onset temperatures (air) in the 213–353, 167–240, and 230–307 °C ranges, respectively. Additionally, the decomposition temperatures of these ionic liquids are highly dependent on the nature of the anion.  相似文献   

19.
Synthesis and Structure of New Sodium Hydrogen Sulfates Na(H3O)(HSO4)2, Na2(HSO4)2(H2SO4), and Na(HSO4)(H2SO4)2 Three acidic sodium sulfates have been synthesized from the system sodium sulfate/sulfuric acid and have been crystallographically characterized. Na(H3O)(HSO4)2 ( A ) crystallizes in the space group P21/c with the unit cell parameters a = 6.974(2), b = 13.086(2), c = 8.080(3) Å, α = 105.90(4)°, V = 709.1 Å3, Z = 4. Na2(HSO4)2(H2SO4) ( B ) is orthorhombic (space group Pna21) with the unit cell parameters a = 9.970(2), b = 6.951(1), c = 13.949(3) Å, V = 966.7 Å3 and Z = 4. Na(HSO4)(H2SO4)2 ( C ) crystallizes in the triclinic space group P1 with the unit cell parameters a = 5.084(1), b = 8.746(1), c = 11.765(3) Å, α = 68.86(2)°, β = 88.44(2)°, γ = 88.97(2)°, V = 487.8 Å3 and Z = 2. All three compounds contain SO4 tetrahedra as HSO4? anions and additionally in B and C in form of H2SO4 molecules. The ratio H:SO4 determines the connectivity degree in the hydrogen bond system. In A , there are zigzag chains and dimers additionally connected via oxonium ions. Complex chains consisting of cyclic trimers (two HSO4? and one H2SO4) are present in B . In structure C , several parallel chains are connected to columns due to the greater content of H2SO4. Sodium cations show a distorted octahedral coordination by oxygen in all three structures, the NaO6 octahedra being “isolated” (connected via SO4 tetrahedra only) in A . Pairs of octahedra with common edge form Na2O10 dimeric units in C . Such double octahedra are connected via common corners forming zigzag chains in B .  相似文献   

20.
Summary In this paper, experimental results obtained by the in-situ radiotracer and voltammetric studies of the competitive adsorption of the HSO4-/SO42- (labeled with 35S) and Cl- (labeled with 36Cl) anions on bare Aupoly substrate and Aupoly surfaces modified by the Zn adatoms in the lower pH region (pH≤4.5) are presented and discussed. In addition, some data on the formation of Zn adlayers (labeled with 65Zn) are reported to demonstrate the complex features of the underpotential deposition (UPD) phenomenon. It has been revealed that (1) the relative adsorption strength of Cl- ions on bare Aupoly is higher than that of H2PO4-/PO43- and HSO4-/SO42- ions in the entire pH region studied; (2) anomalous tendency of the specific adsorption of anions on polycrystalline gold modified by Zn adatoms occurs at pH 4.5 as follows: PO43->SO42->Cl->>ClO4- and (3) the UPD of Zn2+ ions on polycrystalline gold is measurable even from solutions containing 5 . 10-8M Zn2+ over the entire potential range where the hydrogen evolution takes place.It is, however, plausible to assume that the coverage of the gold surface by Zn adatoms measured even at solution concentrations of c≥5 . 10-4M does not exceed one monolayer.  相似文献   

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