Bifunctional Ionic Liquid Research Articles

Synthesis and property of imidazolium oxidative-thermoregulated ionic liquids

A series of novel imidazolium oxidative-thermoregulated bifunctional ionic liquids (ILs) have been synthesized by introducing the thermoregulated structural unit into imidazolium cation and using heteropolyanion as the anion of ILs. The structures of these new type of task-specific ionic liquids (TSILs) are characterized by FT-IR and 1H NMR. The thermostability of ILs is analyzed by thermogravimetry. The thermoregulated properties of ILs in aqueous and organic solvents are mainly investigated. These ILs have the corresponding cloud points (CPs) in aqueous. The effects of IL concentration, polymerization degree, inorganic additives and organic additives on the CP are studied. IL/DMF/n-heptane or n-octane biphasic system has the corresponding critical solution temperature (CST), and has the feature of “homogeneous at high temperature, heterogeneous at low temperature”. The effects of IL dosage and polymerization degree on the CST are given. IL/DMF/n-octane thermoregulated biphasic system has been successfully applied for catalytic oxidative desulfurization of model fuels. This study opens up a new way for catalytic oxidation to achieve an integration of homogeneous catalysis and heterogeneous separation.

Cationic derivatives of the plant resistance inducer benzo[1,2,3]thiadiazole-7-carbothioic acid S-methyl ester (BTH) as bifunctional ionic liquids

We have synthesized, new salt derivatives of benzo[1,2,3]thiadiazole-7-carbothioic acid S-methyl ester (BTH) containing BTH as the cation in combination with anions, which modify the physical and antibacterial properties of the resulting product while preserving the systemic acquired resistance (SAR) induction properties. The obtained compounds were tested toward induction of resistance in tobacco (Nicotiana tabacum var. Xanthi), which was later infected with OLV-1 and TMV viruses. Moreover in vitro tests on bacteria confirmed the preservation of antibacterial properties brought about by a docusate anion.

Patterning a π-conjugated polyelectrolyte through sequential polymerization of a bifunctional ionic liquid monomer

An electronically conductive polyelectrolyte is prepared by the sequential polymerization of a bifunctional imidazolium-based ionic liquid (IL) monomer, composed of a thienyl and vinyl containing cation paired with a tetrafluoroborate anion. In the first step, potentiodynamic electropolymerization of the thienyl moiety forms a cationic polyalkylthiophene that is soluble in select organic solvents. Cyclic voltammetry (CV) was used to determine the polymer p-doping potential (0.31 V) and the bipolaronic state (1.49 V). The polymer exhibits electrochromism, converting from red in the neutral state (λmax = 443 nm) to dark blue in the polaronic state (λmax = 819 nm). The solution-processable polymer can be cast into a film, masked and patterned by UV-initiated free radical polymerization of the vinyl moiety. Small-angle X-ray scattering (SAXS) revealed that the insoluble crosslinked polyalkylthiophene–polyvinylimidazolium adopts a lamellar structure with a lattice spacing of 3.3 nm. Four-probe d.c. conductivity measurements determined the de-doped electrical conductivity was 1.0 × 10−2 S/cm. The results underscore the importance of the anion in controlling the polymerization of IL monomers.

Oxidative Desulfurization of Model Diesel with O2Catalyzed by Oxidative-thermoregulated Bifunctional Ionic Liquids

将温控结构单元聚醚链和催化氧化基团磷钨酸根共同引入到离子液体的结构中,合成出一系列不同聚合度的十八胺类氧化-温控双功能离子液体,并将其应用于催化O2氧化模拟柴油的脱硫反应过程,实现了反应分离一体化,并取得了良好的脱硫效果和催化剂循环使用效果.该类离子液体在甲苯/正十二烷混合溶剂中具有良好的温控性能.筛选出活性较高的离子液体催化剂,其聚合度n=111以及烷基碳链为C12.考察了反应温度、反应时间和氧气压力等因素对脱硫效果的影响.在优化的反应条件(V(甲苯)∶V(模拟油)=1∶1,T=100℃,t=2 h,p(O2)=2.0 MPa)下,DMF萃取一次,脱硫率接近100%.催化剂循环使用11次,脱硫率仍可达到95%以上.

Extraction mechanism of cerium(IV) in H2SO4/H3PO4 system using bifunctional ionic liquid extractants

The extraction of Ce(IV) in H2SO4/H3PO4 system was investigated systematically using bifunctional ionic liquid extractants (Bif-ILES) [A336][P507], [A336][P204] and [A336][C272] in n-heptane. The effects of H2SO4 concentration, extractant concentration and salting-out agent concentration were observed in detail. The extraction mechanism of Ce(IV) in H2SO4/H3PO4 system was obtained. The comparison with other extractants such as Cyanex923, TBP was also studied. Thermodynamic functions of the extraction reaction were calculated, showing that the extraction was an exothermic process. The separation of Ce(IV) from RE(III) and Th(IV) was also investigated. The result indicated that Ce(IV) could be selectively extracted in this system. CePO4 nanoparticles were obtained in the process of stripping using H2O2 in H2SO4/H3PO4 system. X-ray diffraction (XRD), scanning electron microscopy (SEM) and spectroscopy were adopted for the characterization of the sample.

Conversion of cellulose to HMF in ionic liquid catalyzed by bifunctional ionic liquids

A new kind of bifunctional ionic liquid catalysts was synthesized to degrade microcrystalline cellulose in [BMIM]Cl at atmospheric pressure. The effects of reaction temperature, amount of catalysts, reaction time, ionic liquid purity and cellulose concentration on conversion were investigated. At low temperature cellulose can be degraded with being heated in [BMIM]Cl by oil bath. Among the as-synthesized catalysts, Cr([PSMIM]HSO4)3 exhibited the best performance. The HMF yield of 53% and TRS yield of 94% can be achieved at 120°C in [BMIM]Cl for 5h over 0.05g Cr([PSMIM]HSO4)3/2.0g [BMIM]Cl with 95% cellulose conversion.

ChemInform Abstract: Facile Preparation and Reactivity of Bifunctional Ionic Liquid Supported Hypervalent Iodine Reagent: A Convenient Recyclable Reagent for Catalytic Oxidation.

AbstractTEMPO derivatives (I) and (II) are synthesized and successfully tested as recycable catalysts for the peracid oxidation of a broad spectrum of primary and secondary alcohols to the corresponding carbonyl compounds.

Bi-Functional Magnetical Chiral Ionic Liquids Derived from Imidazolium and Pyridinium

Novel Bi-Functional Magnetical Chiral Ionic Liquids (MCILs) Derived from Imidazolium and Pyridinium Were Synthesized via Simply Two Step Reactions. Optically Active Ionic Liquids Have an Asymmetric Carbon Atom Linked to the Positively Charged Imidazole Ring or Pyridine Ring, while the Magnetical Anion Contains Tetrachloroferrate (FeCl4-), their Properties of Chirality and Magnetism Were Characterized. the Structure of MCILs Would Promise a New Class of Bi-Functional Ionic Liquids.

Preparation of Poly(vinylidene fluoride-co-tetrafluoroethylene)-Based Polymer Inclusion Membrane Using Bifunctional Ionic Liquid Extractant for Cr(VI) Transport

A series of novel polymer inclusion membranes (PIMs) were prepared and applied in Cr(VI) transport. The PIMs were composed of bifunctional ionic liquid extractant (Bif-ILE) [trialkylmethylammonium][bis(2,4,4-trimethylpentyl)phosphinate] ([A336][C272]), [trialkylmethylammonium][di-2-ethylhexylphosphinate] ([A336][P204]), or [trialkylmethylammonium][di-(2-ethylhexyl)orthophosphinate] ([A336][P507]) as the carrier, 1-octyl-3-methylimidazolium hexafluorophosphate or tetrafluoroborate ([C8mim][PF6] or [BF4]) as the ionic liquid plasticizer (ILP), and poly(vinylidene fluoride-co-tetrafluoroethylene) (PVDF) as the polymer. ILP played a key role for the permeability coefficient (P). The maximum P values of [A336][C272], [A336][P204], and [A336][P507] PIMs were 1.39, 1.41, and 0.66 times higher than that without the plasticizer, respectively. The HCl concentration in the feed phase and NaOH concentration in the stripping phase had effects on the flux of Cr(VI). The maximum initial flux (Ji) was 40.08 μmol m–2 s–1 using the [A336][P204] PIM when the initial HCl concentration in the feed phase was 0.20 mol L–1 and the NaOH concentration in the stripping phase was 0.05 mol L–1. The selectivity of three PIMs followed as [A336][P204] ≈ [A336][P507] > [A336][C272]. Compared with Cyphos IL 104, the P value of Cr(VI) using [A336][C272], [A336][P204], or [A336][P507] was all higher than using Cyphos IL 104.

Bifunctional Ionic Liquid Catalyst Containing Sulfoacid Group and Hexafluorotitanate for Room Temperature Sulfoxidation of Sulfides to Sulfoxides Using Hydrogen Peroxide

A bifunctional ionic liquid (IL), bis-[N-(propyl-1-sulfoacid)-pyridinium] hexafluorotitanate (1), was synthesized and proved to be an efficient and recyclable catalyst for room temperature sulfoxidation of sulfides using H2O2 as the oxidant. The synergetic catalysis derived from the incorporated functional moieties in the IL structure was embodied in 1. The UV–vis and Raman spectra indicated that the remarkable catalytic performance of 1 was related to the easy generation and regeneration of the active peroxo-Ti species.

Recovery of rare earth elements from simulated fluorescent powder using bifunctional ionic liquid extractants (Bif‐ILEs)

AbstractBACKGROUND:Numerous high purity ammonium‐type ionic liquid extractants have been prepared for engineering purposes. Bifunctional ionic liquid extractants (Bif‐ILEs) have been widely applied to separate and extract rare earths and metal ions with high extraction efficiencies and selectivities. In the present study, new Bif‐ILEs [A336][P204] and [A336][P507] have been used to extract rare earths from a simulated solution of a fluorescent powder in a high concentration of Al(NO3)3.RESULTS:Bif‐ILEs were prepared from Aliquat336 (A336) and the commercial organophosphorus acid extractants, P204 and P507. These extractants [A336][P204] and [A336][P507] have similar characteristics to neutral organophosphorus extractants. When these Bif‐ILEs were used to extract RE(III) from a simulated waste fluorescent powder system a third phase appeared which could be eliminated by the addition of 10% isopropanol modifier. The coexisting Al2O3in the fluorescent powder was changed to a salting‐out agent (Al(NO3)3) in the extraction process and promoted the extraction efficiency of RE(III). Using a countercurrent extraction process at a phase ratioVo:Vw= 4:1 and pH = 0.56, the RE(III) recovery reached 95.2% in 5–7 stages. Finally, the extractabilities of these bifunctional extractants were compared with the neutral organophosphorus extractants P350, TBP and Cyanex923 at different concentrations, initial pHs and temperatures.CONCLUSIONS:By comparison with other neutral organophosphorus extractants, Bif‐ILEs [A336][P204] and [A336][P507] can be considered efficient potential extractants for separating and recycling REEs and Al2O3from waste fluorescent powder. Copyright © 2011 Society of Chemical Industry

Extraction and recovery of cerium(IV) and fluorine(I) from sulfuric solutions using bifunctional ionic liquid extractants

The extraction of cerium(IV) (Ce(IV)), fluorin (F −) and Ce(IV)–F mixture solution from sulfuric acid medium using bifunctional ionic liquid extractants (Bif-ILEs) [trialkylmethylammonium][di-(2-ethylhexyl)orthophosphinate] ([A336][P507]), [trialkylmethylammonium][di-2-ethylhexylphosphinate] ([A336][P204]) and [trialkylmethylammonium][bis 2,4,4-trimethylpentylphosphinate] ([A336][C272]) in n-heptane have been investigated in this report. The effect of H 2SO 4 concentration, extractant concentration and salting-out agent concentration has been investigated. The thermodynamic parameters have been determined, showing that the extraction was exothermic. The extraction mechanism has been obtained. The comparison for the extraction of Ce(IV), Ce(IV) in Ce(IV)–F mixture solution, cerium(III) (Ce(III)) and thorium(IV) (Th(IV)) has been investigated and the extraction efficiency order followed as: Ce(IV) > Th(IV) > Ce(III). Ce(IV) in Ce(IV)–F mixture solution was extracted in the form of CeF 3+. The highest separation factor ( β) values of Ce(IV)/Ce(III) and CeF 3+/Ce(III) were 3.32 × 10 3 and 2.58 × 10 3 in the [A336][P507] extraction system, 7.27 × 10 2 and 6.94 × 10 2 in the [A336][P204] extraction system, and 1.84 × 10 2 and 2.75 × 10 2 in the [A336][C272] extraction system, respectively, which indicated that Ce(IV) and Ce(IV) in Ce(IV)–F mixture solution could be separated from Ce(III) effectively.

Application of Bifunctional Ionic Liquid Extractants [A336][CA-12] and [A336][CA-100] to the Lanthanum Extraction and Separation from Rare Earths in the Chloride Medium

In this Article, bifunctional ionic liquid extractants (Bif-ILEs) tricaprylmethylammonium sec-octylphenoxy acetic acid ([A366][CA-12]) and tricaprylmethylammonium sec-nonylphenoxy acetic acid ([A336][CA-100]) used for the rare earths (REs) extraction from the chloride medium have been investigated. The effects of extractants concentration, equilibrium pH of aqueous phase, salt concentration, temperature, etc., were discussed. The results show that the extraction ability of [A336][CA-12] and [A336][CA-100] is higher than that of the conventional extractants sec-octylphenoxy acetic acid (CA-12), sec-nonylphenoxy acetic acid (CA-100), tri-n-butyl phosphate (TBP), and di-(1-metylheptyl)methyl phosphate (P350) under the same conditions. Furthermore, in the [A336][CA-12] system, the separation factors (beta) between La(III) and other REs(III) are higher than 6.0, which indicates that [A336][CA-12] would be suitable for the La(III) extraction and separation. The extraction mechanism is also proposed, and there is a similar extraction tendency in both the [A336] [CA-12] and the [A336][CA-100] systems. The loaded organic phase is easy to strip; more than 95% La(III) could be stripped from the loaded organic phase when the stripping acidity is higher than 0.03 M. The recycling experiments also indicate that the two extraction systems could be recycled without loss of the extraction efficiency.

Toward greener separations of rare earths: Bifunctional ionic liquid extractants in biodiesel

AbstractIonic liquids (ILs) containing quaternary phosphonium cations and phosphonic acid anions were explored as novel extractants for rare earths (RE) separation. They were considered to be bifunctional ionic liquid extractants (bif‐ILEs), since both cations and anions of ILs were involved in the extraction. Trihexyl(tetradecyl)phosphonium bis 2,4,4‐trimethylpentylphosphinate (Cyphos IL 104), as a bif‐ILE, together with propylene carbonate (PC), dimethyl carbonate (DMC), and soybean oil methyl ester (SBME, biodiesel) as diluents was employed in the extraction of RE(III) from aqueous solutions. Acidified Cyphos IL 104 (HNO3‐Cyphos IL 104) exhibited high solubility in three diluents, and higher extraction efficiency than bis(2,4,4‐trimethylpentyl)phosphinic acid (Cyanex 272) because of the coextraction of RE(III) by quaternary phosphonium cation and phosphonic acid anion in organic phase. Additionally, this coextraction mechanism could eliminate the loss of IL. The physical properties and miscibility test results indicated that SBME was an excellent solvent for RE(III) extraction. © 2010 American Institute of Chemical Engineers AIChE J, 2010

Separation of cobalt and nickel using inner synergistic extraction from bifunctional ionic liquid extractant (Bif-ILE)

The inner synergistic extraction of [tricaprylmethylammonium][sec-octylphenoxy acetate] ([A336][CA-12]) is studied for cobalt and nickel separation. Distribution ratios of [A336][CA-12] for Co 2+ or Ni 2+ are by far higher than those of tricaprylmethylammonium sulfate ([A336] 2SO 4), sec-octylphenoxy acetic acid (CA-12), mixture of [A336] 2SO 4 and CA-12 at the acidities from 1 × 10 −5 mol L −1 to 1 × 10 −3 mol L −1. The synergy coefficients of [A336][CA-12] for Co 2+ are higher than the synergy coefficients of [A336][CA-12] for Ni 2+, which can be used for the Co 2+ and Ni 2+ separation. Some thermodynamic properties of the inner synergistic extraction using [A336][CA-12] for Co 2+ and Ni 2+ are also studied, such as influence of temperature, thermodynamic functions, extraction mechanism, separation factors and stripping properties.

Experimental and theoretical investigation of reaction of aniline with dimethyl carbonate catalyzed by acid–base bifunctional ionic liquids

Acid–base bifunctioanal ionic liquid, 1-(2-(1′-piperidinyl) ethyl)-3-methyl imidazolium trichlorolead ([PEmim]PbCl 3), is an efficient catalyst for the reaction of aniline and dimethyl carbonate (DMC). The [PEmim]PbCl 3 catalyzed reaction gives methyl-N-methyl-N-phenylcarbamate in the yield of 72%, while the basic ionic liquid, 1-(2-(1′-piperidinyl) ethyl)-3-methyl imidazolium chloride, and the acidic PbCl 2 give the yields of 47% and 6%, respectively. The high reactivity of [PEmim]PbCl 3 is accounted for its ability to activate both aniline and DMC by the acidic and basic sites cooperatively. Density functional theory (DFT) calculations simulate the structures and charge properties of [PEmim]PbCl 3, complex of [PEmim]PbCl 3 and aniline, and complex of [PEmim]PbCl 3 and DMC. The calculations show that [PEmim]PbCl 3 can increase the electrophilicity of DMC and the nucleophilicity of aniline by its acid and base sites.

The inner synergistic effect of bifunctional ionic liquid extractant for solvent extraction

The inner synergistic effect of bifunctional ionic liquid extractant (Bif-ILE) for solvent extraction is reported for the first time using [tricaprylmethylammonium][di-2-ethylhexylphosphinate] ([A336][P204]) as n extractant for Eu(III), which can be attributed to better stability and hydrophobicity of the complex formed by [A336][P204] with Eu(III). Some other Bif-ILEs are also found to have the similar inner synergistic effect. Distribution coefficient, stripping property and extraction mechanism of the novel extraction protocol are discussed in this report. The study contributes towards acquiring a new understanding of synergistic extraction and task specific ionic liquid (TSIL), furthermore, providing a positive influence on their potential application in analytical chemistry.

Silica Materials Doped with Bifunctional Ionic Liquid Extractant for Yttrium Extraction

Two new silica-based organic−inorganic hybrid materials (B104SGs and O104SGs) doped with a binary mixture of imidazolium and phosphonium ionic liquids have been synthesized and used as sorbents in batch system for rare earths (RE) separation. Imidazolium ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate (C4mim+PF6−) or 1-octyl-3-methylimidazolium hexafluorophosphate (C8mim+PF6−) acted as porogens to prepare porous materials and additives to stabilize extractant within silica gel. Trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate (Cyphos IL 104), a low-molecular-mass organic gelator, can encourage the formation of porous silica materials and increase the rate of aggregation. Cyphos IL 104 not only acted as an excellent template for the preparation of silica sorbents but also as a bifunctional ionic liquid extractant (bif-ILE) for RE(III) extraction. By the electrostatic attraction between the SiO- groups and phosphonium cations along the surfaces of the silica gel, stable si...