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Lu Bai

Bio: Lu Bai is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Ionic liquid & Membrane. The author has an hindex of 20, co-authored 61 publications receiving 1583 citations.


Papers
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Journal ArticleDOI
TL;DR: The effects of anions, cations and functional groups on CO2 solubility and selectivity ofILs, as well as the studies on degradability of ILs are reviewed, and the recent developments on functionalized ILs, IL- based solvents, and IL-based membranes are discussed.
Abstract: The inherent structure tunability, good affinity with CO2, and nonvolatility of ionic liquids (ILs) drive their exploration and exploitation in CO2 separation field, and has attracted remarkable interest from both industries and academia. The aim of this Review is to give a detailed overview on the recent advances on IL-based materials, including pure ILs, IL-based solvents, and IL-based membranes for CO2 capture and separation from the viewpoint of molecule to engineering. The effects of anions, cations and functional groups on CO2 solubility and selectivity of ILs, as well as the studies on degradability of ILs are reviewed, and the recent developments on functionalized ILs, IL-based solvents, and IL-based membranes are also discussed. CO2 separation mechanism with IL-based solvents and IL-based membranes are explained by combining molecular simulation and experimental characterization. Taking into consideration of the applications and industrialization, the recent achievements and developments on the t...

613 citations

Journal ArticleDOI
01 Jan 2013-Fuel
TL;DR: In this paper, a series of Lewis acidic ionic liquids (ILs), dialkylpyridinium tetrachloroferrates [(C4MPy)-M-3] FeCl4, [C8MPy]-M-2] FeCL4, and [C 8MPy-M-1]-FeCl4 were synthesized and utilized as extractant and catalyst to investigate the oxidative removal of dibenzothiophene (DBT) from model oil, with 30 wt% hydrogen peroxide (H2O2) solution

126 citations

Journal ArticleDOI
TL;DR: In this paper, a facile and scalable method for the fabrication of cellulose-based asymmetric carbon hollow fiber membranes (CHFMs) with ultramicropores of 3-4
Abstract: Carbon molecular sieve (CMS) membranes with rigid and uniform pore structures are ideal candidates for high temperature- and pressure-demanded separations, such as hydrogen purification from the steam methane reforming process. Here, we report a facile and scalable method for the fabrication of cellulose-based asymmetric carbon hollow fiber membranes (CHFMs) with ultramicropores of 3–4 A for superior H2 separation. The membrane fabrication process does not require complex pretreatments to avoid pore collapse before the carbonization of cellulose precursors. A H2/CO2 selectivity of 83.9 at 130 °C (H2/N2 selectivity of >800, H2/CH4 selectivity of >5700) demonstrates that the membrane provides a precise cutoff to discriminate between small gas molecules (H2) and larger gas molecules. In addition, the membrane exhibits superior mixed gas separation performances combined with water vapor- and high pressure-resistant stability. The present approach for the fabrication of high-performance CMS membranes derived from cellulose precursors opens a new avenue for H2-related separations. Energy-efficient hydrogen purification technologies are needed for the hydrogen economy. Here the authors report facile and scalable fabrication of asymmetric carbon molecular sieve membranes for the separation of hydrogen and carbon dioxide.

98 citations

Journal ArticleDOI
TL;DR: In this article, the effects of ionic liquid anions and ZIF-8 content on gas permeability and selectivity were investigated, and the results showed that the anion of IL is a key factor to determine the CO2 permeability of the membranes, which is similar to the principle of CO2 solubility in pure ILs.
Abstract: Membrane-based separation technology has been reported as one of the possible methods to efficiently and economically separate carbon dioxide (CO2). To provide synergistic enhancements in the gas separation performance, organic polymer (Pebax 1657), zeolite imidazolate framework-8 (ZIF-8) nanoparticles, and ionic liquid (IL) have been integrated to develop three-component composite membranes. To achieve high separation performance of three-component membranes, the effects of IL anions and ZIF-8 content on gas permeability and selectivity were investigated first. The ILs were 1-butyl-3-methyl imidazolium ([Bmim]) cation based on different anions of bis(trifluoromethylsulfonyl)imide ([NTf2]), dicyanamide ([DCA]), and tetrafluoroborate ([BF4]). Gas transport properties of all the prepared membranes were investigated at 23 °C and 1 bar. The results showed that the anion of IL is a key factor to determine the CO2 permeability of the membranes, which is similar to the principle of CO2 solubility in pure ILs. In addition, ZIF-8 could increase both CO2 diffusivity and solubility coefficients of the Pebax/ZIF-8 membranes, resulting in a two-fold increase in the CO2 permeability. For the Pebax/ZIF-8(15%)/[Bmim][NTf2] membranes, it has been revealed that [Bmim][NTf2] acts as a low molecular weight additive, leading to a more amorphous structure and a higher FFV (fractional free volume) of the membranes, which are beneficial for gas diffusion. The addition of IL can improve the compatibility between the inorganic particles and the polymer matrix; thus, the non-selective voids decrease, which leads to a higher CO2/N2 selectivity. The CO2 permeability of the Pebax/ZIF-8(15%)/IL(80%) membrane was 4.3 times that of the pure Pebax membrane without sacrificing the CO2/N2 selectivity. Therefore, the high gas transport properties of the Pebax/ZIF-8/IL membranes make them promising candidates for CO2-effective separation materials.

94 citations

Journal ArticleDOI
TL;DR: In this article, a series of novel ether-functionalized pyridinium chloride Ionic liquids (ILs) were designed and synthesized to improve the absorption capacities of ILs for SO2, and the physicochemical properties of these ILs and their SO2 absorption performance under different conditions were investigated.
Abstract: Sulfur dioxide (SO2) emitted from the combustion of fossil flues is a major atmospheric pollutant that seriously threatens the environment and human health The traditional methods for the removal and recovery of SO2 are irreversible and can result in secondary pollution or suffer from solvent loss Therefore, it is urgent to explore new absorbents for the reversible, efficient, and environment-friendly capture of SO2 Ionic liquids (ILs) exhibit excellent performance for SO2 capture because of their unique physicochemical properties To improve the absorption capacities of ILs for SO2, a series of novel ether-functionalized pyridinium chloride ILs ([EnPy]Cl, n = 2–4) were designed and synthesized The physiochemical properties of these ILs and their SO2 absorption performance under different conditions were investigated In addition, the SO2/CO2 selectivities and reusabilities of the ILs and the absorption mechanism between SO2 and [EnPy]Cl (n = 2–4) were studied It was found that 1-[2-(2-methoxyethoxy)

82 citations


Cited by
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01 Feb 1995
TL;DR: In this paper, the unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio using DFT, MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set.
Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

1,652 citations

Journal ArticleDOI
TL;DR: Deep eutectic solvents (DESs) have been considered as alternatives to ILs that maintain most of their relevant properties, such as task-specific character, and at the same time avoid some of their problems, mainly from economic and environmental viewpoints as discussed by the authors.
Abstract: Sustainable technologies applied to energy-related applications should develop a pivotal role in the next decades. In particular, carbon dioxide capture from flue gases emitted by fossil-fueled power plants should play a pivotal role in controlling and reducing the greenhouse effect. Therefore, the development of new materials for carbon capture purposes has merged as central research line, for which many alternatives have been proposed. Ionic liquids (ILs) have emerged as one of the most promising choices for carbon capture, but in spite of their promising properties, some serious drawbacks have also appeared. Deep eutectic solvents (DESs) have recently been considered as alternatives to ILs that maintain most of their relevant properties, such as task-specific character, and at the same time avoid some of their problems, mainly from economic and environmental viewpoints. DES production from low-cost and natural sources, together with their almost null toxicity and total biodegradability, makes these sol...

719 citations

Journal ArticleDOI
TL;DR: It is expected that the fundamental properties of PILs will continue to be explored, along with continued interest in many existing and new applications, such as in electrochemistry, organic and inorganic synthesis, and biological applications.
Abstract: The thermal and physicochemical properties of protic ionic liquids (PILs) are reported. It is highly evident that there has been an extensive range of alkylammonium, imidazolium, and heterocyclic cations paired with many organic and inorganic anions that have been employed to prepare PILs. There has been strong interest in modifying the properties of PILs through the addition of water or other molecular solvents. For many applications, the presence of some water in the PILs is not detrimental, and instead leads to enhanced solvent properties such as lower viscosity, higher conductivities, and lower melting points. It remains an issue of definition though of how to refer to these resulting protic solutions. There is also an ongoing difficulty surrounding how to describe the proton activity in the PILs, analogous to pH in aqueous systems. For a broad range of applications, it has been reported that the acidity/basicity of the PIL or PIL-solvent system is crucial for their beneficial properties. It is expected that the fundamental properties of PILs will continue to be explored, along with continued interest in many existing and new applications, such as in electrochemistry, organic and inorganic synthesis, and biological applications. In particular, there has been a significant interest in a broad- range of PILs for use as electrolytes and incorporation in polymer electrolytes for fuel cells, and other energy storage devices.

676 citations

Journal ArticleDOI
TL;DR: The effects of anions, cations and functional groups on CO2 solubility and selectivity ofILs, as well as the studies on degradability of ILs are reviewed, and the recent developments on functionalized ILs, IL- based solvents, and IL-based membranes are discussed.
Abstract: The inherent structure tunability, good affinity with CO2, and nonvolatility of ionic liquids (ILs) drive their exploration and exploitation in CO2 separation field, and has attracted remarkable interest from both industries and academia. The aim of this Review is to give a detailed overview on the recent advances on IL-based materials, including pure ILs, IL-based solvents, and IL-based membranes for CO2 capture and separation from the viewpoint of molecule to engineering. The effects of anions, cations and functional groups on CO2 solubility and selectivity of ILs, as well as the studies on degradability of ILs are reviewed, and the recent developments on functionalized ILs, IL-based solvents, and IL-based membranes are also discussed. CO2 separation mechanism with IL-based solvents and IL-based membranes are explained by combining molecular simulation and experimental characterization. Taking into consideration of the applications and industrialization, the recent achievements and developments on the t...

613 citations

Journal ArticleDOI
TL;DR: This article provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.
Abstract: Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

604 citations