Co-reporter:Di Bao;Suojiang Zhang;Haifeng Dong;Ying Huang;Xin Zhang
Industrial & Engineering Chemistry Research January 8, 2014 Volume 53(Issue 1) pp:428-439
Publication Date(Web):2017-2-22
DOI:10.1021/ie4020827
Adding a small amount of water to ionic liquids can greatly reduce the viscosities of ionic liquids, which is believed to be an effective and economical method to make ionic liquids being applied practically for carbon capture. However, how the water content influences the bubble behavior which is used to calculate transfer properties; this is important but has not been studied systematically. In this work, the rise and deformation of single CO2 bubbles in ionic liquids with different water contents were investigated using a high speed image pickup system. The results indicate that a small amount of water has a significant influence on the bubble behavior in ionic liquids. The viscosity plays a more important role in determining the bubble behavior than the surface tension. Two new empirical correlations verified by experimental data were proposed to predict bubble velocity and bubble diameter in different ionic liquid systems.
Co-reporter:Zhijie Li, Xiangping Zhang, Haifeng Dong, Xiaochun Zhang, Hongshuai Gao, Suojiang Zhang, Jianwei Li and Congmin Wang
RSC Advances 2015 vol. 5(Issue 99) pp:81362-81370
Publication Date(Web):16 Sep 2015
DOI:10.1039/C5RA13730F
Ammonia (NH3) emitted from the ammonia synthesis process is a kind of waste chemical resource and a major environmental pollutant. The traditional water scrubbing method suffers from high energy consumption due to the concentrated NH3 from aqueous ammonia. Therefore, it is desirable to develop novel absorbents for the efficient, reversible and environmentally-friendly recovery of NH3. In this paper, a series of hydroxyl-functionalized imidazolium ILs ([EtOHmim]X, X = [NTf2], [PF6], [BF4], [DCA], [SCN] and [NO3]) were designed and prepared. Their physical properties and NH3 absorption capacities under different temperatures and pressures were systematically investigated. The effects of hydroxyl cation, anionic structures, pressure and temperature on absorption performance were sufficiently studied. In addition, the absorption mechanism was investigated in detail by spectral analysis and quantum chemistry calculations. Compared with conventional IL [Emim]X, a higher absorption capacity was achieved by introducing the hydroxyl group on the imidazolium cation. The mechanism results showed the fascinating absorption performance of the task-specific ILs was attributed to the stronger hydrogen bonding interaction between NH3 and the H atom of the hydroxyl group. Considering the excellent absorption performance, high thermal stability, and super reversibility, this type of IL provides great improvement over conventional IL and shows their enormous potential in NH3 recovery.
Co-reporter:Shaojuan Zeng, Hongyan He, Hongshuai Gao, Xiangping Zhang, Jian Wang, Ying Huang and Suojiang Zhang
RSC Advances 2015 vol. 5(Issue 4) pp:2470-2478
Publication Date(Web):02 Dec 2014
DOI:10.1039/C4RA13469A
In this work, three kinds of novel functionalized ionic liquids (ILs) [NEt2C2Py][SCN], [C4OPy][SCN] and [C4CNPy][SCN] were developed by introducing a tertiary amino group, ether group and nitrile group on the pyridinium cation to improve SO2 absorption performances. Among the investigated ILs, [NEt2C2Py][SCN] showed the highest absorption capacity of 1.06 gSO2 gIL−1 under ambient conditions due to a combination of chemical and physical absorption. By contrast, the enhancement in SO2 capacity by [C4CNPy][SCN] and [C4OPy][SCN] is mainly ascribed to the stronger physical interaction between ILs and SO2 than the conventional IL [C4Py][SCN]. Meanwhile, higher SO2/CO2 selectivity was also obtained using these functionalized ILs, which was increased up to 41% comparing with that of [C4Py][SCN]. Moreover, the effect of water on SO2 capacity and the absorption mechanism were studied. The results indicated that the presence of water caused a slight decrease in SO2 capacity of [C4CNPy][SCN] and [C4OPy][SCN] because of physical absorption, whereas a slight increase in SO2 capacity by [NEt2C2Py][SCN] due to the formation of hydrogen sulfite salts through chemical absorption. In addition, three kinds of cation-functionalized ILs could remain the stable absorption performance after five cycles of absorption and desorption, implying these ILs show great potentials for SO2 capture.
Co-reporter:Lu Bai, Yi Nie, Yi Li, Haifeng Dong, Xiangping Zhang
Fuel Processing Technology 2013 Volume 108() pp:94-100
Publication Date(Web):April 2013
DOI:10.1016/j.fuproc.2012.04.008
Asphaltenes in direct coal liquefaction residue (DCLR) are highly aromatic and polydisperse mixtures, which are important precursors for producing high value-added carbon materials. In this research, a series of protic ionic liquids (PILs) with organic carboxylate anions were synthesized and applied to extract asphaltenes from DCLR at room temperature. The extracts were characterized by elemental analysis, FTIR, 13C-NMR, quinoline insolubles tests and so on. The results show that asphaltenes with the potential of precursors of carbon materials can be separated from DCLR at room temperature using PILs and the solid–liquid separation is carried out facilely due to the lower viscosities of PILs. The influences of PILs structures on extraction yields and atomic ratios of H/C were also investigated. As alkyl chain length of PILs anions increases, extraction yields of asphaltenes increase while H/C ratios decrease. Moreover, extraction yields vary with various cations of PILs and increase according to the order of N-methylimidazolium ([MIM]+) < triethylammonium ([TEtA]+) < 3-methylpyridinium ([MPy]+), but H/C ratios decrease following the order of N-methylimidazolium ([MIM]+) > triethylammonium ([TEtA]+) > 3-methylpyridinium ( [MPy]+). The asphaltenes extracted from DCLR with PILs have the excellent properties for preparing carbon materials, such as lower H/C ratios, higher aromaticities, lower sulfur contents and nearly no quinoline insolubles.Highlights► Protic ionic liquids were used to extract asphaltenes from DCLR at room temperature. ► The solid-liquid separation was carried out easily and quickly. ► The structures of protic ionic liquids influence the properties of extracts. ► Extracts have excellent properties including lower H/C and higher aromaticities.
Co-reporter:Xiangping Zhang, Xuezhong He, and Truls Gundersen
Energy & Fuels 2013 Volume 27(Issue 8) pp:4137-4149
Publication Date(Web):March 4, 2013
DOI:10.1021/ef3021798
A systematic method that integrates process simulation, capture cost estimation, and exergy analysis is applied to evaluate a gas separation membrane process for post-combustion carbon capture in a coal power plant. The influences of membrane performance and process configuration on the energy consumption, required membrane area, and capture cost have been studied. The results indicate that the energy consumption decreases with the increase of CO2/N2 selectivity, but a larger membrane area is required, while for a high CO2 permeance, the membrane area can be significantly reduced. The carbon capture ratio influences the specific energy consumption as well, which should be a trade off. For a two-stage membrane process, the capture load distribution between the first and second stage affects the separation performance greatly, and the optimal range varies with the other parameters. Under the assumptions in this work, the profiles of capture cost related to membrane parameters show that the optimal CO2/N2 selectivity is 70–90. The exergy analysis indicates that the main energy bottleneck of a membrane technology is located in the membrane unit operation, which has relatively low exergy efficiency. On the other hand, CO2 compression has less potential for energy savings because it has already had very high exergy efficiency.
Co-reporter:Jinzhi Zhang, Cai Jia, Haifeng Dong, Jinquan Wang, Xiangping Zhang, and Suojiang Zhang
Industrial & Engineering Chemistry Research 2013 Volume 52(Issue 17) pp:5835-5841
Publication Date(Web):April 3, 2013
DOI:10.1021/ie4001629
A novel dual amino-functionalized ionic liquid, 1, 3-di (2′-aminoethyl)-2-methylimidazolium bromide (DAIL), was synthesized and investigated as a potential absorbent for CO2 capture. CO2 absorption behavior on pressure, temperature and concentrations of DAIL in aqueous solution were studied, and the absorption mechanism was investigated by spectroscopic methods and DFT calculations. The CO2 capture capacity of 18.5 wt % and good thermal stability (Td = 521.6 K) make DAIL a good candidate for industrial applications for CO2 capture.
Co-reporter:Qian Wang;Xingmei Lu;Xueyuan Zhou;Minli Zhu;Hongyan He
Journal of Applied Polymer Science 2013 Volume 129( Issue 6) pp:3574-3581
Publication Date(Web):
DOI:10.1002/app.38706
Abstract
Series of 1-allyl-3-methylimidazolium halometallate ionic liquids (ILs) were synthesized and used to degrade poly(ethylene terephthalate) (PET) as catalysts in the solvent of ethylene glycol. One important feature of these new IL catalysts is that most of them, especially [amim][CoCl3] and [amim][ZnCl3], exhibit higher catalytic activity under mild reaction condition, compared to the traditional catalysts [e.g., Zn(Ac)2], the conventional IL catalysts (e.g., [bmim]Cl), Fe-containing magnetic IL catalysts (e.g., [bmim][FeCl4]), and metallic acetate IL catalysts (e.g., [Deim][Zn(OAc)3]). For example, using [amim][ZnCl3] as catalyst, the conversion of PET and the selectivity of bis(hydroxyethyl) terephthalate (BHET) reach up to 100% and 80.1%, respectively, under atmospheric pressure at 175°C for only 1.25 h. Another important feature is that BHET can be easily separated from the catalyst and has a high purity. Finally, based on the experimental phenomena, in -situ infrared spectra, and experimental results, the possible mechanism of degradation with synthesized IL is proposed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Co-reporter:Lu Bai, Yi Nie, Jincheng Huang, Yi Li, Haifeng Dong, Xiangping Zhang
Fuel 2013 Volume 112() pp:289-294
Publication Date(Web):October 2013
DOI:10.1016/j.fuel.2013.05.035
•Alkylsulfate-based ILs are used to trap asphaltene-type materials from DCLR.•[E4N][ESO4] is a potential solvent to trap asphaltene-type materials from DCLR.•Adding NMP reduce viscosity of [E4N][ESO4] and improve the properties of extracts.•The mechanism of extraction with ILs and IL/NMP mixed solvent is discussed.Alkylsulfate-based ionic liquids (ILs) were synthesized and used as solid–liquid separation solvents to extract asphaltene-type materials from direct coal liquefaction residue (DCLR). Among the ILs employed, tetraethylammonium ethylsulfate ([E4N][ESO4]) was proved to be a potential solvent for trapping asphaltene-type materials from DCLR due to the higher extraction yield and the lower H/C atomic ratio of the extract. N-methyl-2-pyrrolidone (NMP) was added to reduce the viscosity of [E4N][ESO4]. It also increased the extraction yield and decreased H/C atomic ratio of the asphaltene-type materials. The mechanism of extraction might be concluded that the interactions are formed between ILs or [E4N][ESO4]/NMP mixed solvents and asphaltene-type materials, which disturbs the interactions between DCLR and leads to the dissolution of asphaltene-type materials into solvents. The obtained asphaltene-type materials possessed low H/C atomic ratios, high aromaticities, no ashes and no quinoline insolubles, which meet the requirements of preparing carbon materials.
Co-reporter:Lu Bai, Yi Nie, Jincheng Huang, Yi Li, Haifeng Dong, Xiangping Zhang
Fuel 2013 Volume 113() pp:767
Publication Date(Web):November 2013
DOI:10.1016/j.fuel.2013.07.106
Co-reporter:Lu Bai;XiaoLiang Wang;Yi Nie;HaiFeng Dong
Science China Chemistry 2013 Volume 56( Issue 12) pp:1811-1816
Publication Date(Web):2013 December
DOI:10.1007/s11426-013-5016-4
With the wide application of ionic liquids (ILs) in various fields, developing efficient techniques to recover ILs from effluent is an urgent demand for the cost reduction and the environmental protection. In this study, an electrodialysis (ED) method was used to recover 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) IL from aqueous solution as model effluent. The influences of initial IL concentration and applied voltage on the current efficiency, removal ratio, desalination ratio, membrane flux and specific energy consumption during the ED process were investigated. It was found that the removal ratio and desalination ratio increases with the increasing of initial IL concentration and applied voltage. The current efficiency decreases with the increasing of initial IL concentration and the current efficiency reached the maximum value of 94.3% at 25 V. Besides, as the applied voltage increases, the membrane flux increases and the specific energy consumption decreases. Moreover, the fouling of cation-exchange membrane was also discovered after the desalination of IL. The deposits on the surface or into the membrane which is probably caused by [Bmim]+ was characterized by scanning electron microscopy, elemental analysis and Fourier transform infrared.
Co-reporter:Jieli Wang, Hongwei Yao, Yi Nie, Lu Bai, Xiangping Zhang, and Jianwei Li
Industrial & Engineering Chemistry Research 2012 Volume 51(Issue 9) pp:3776-3782
Publication Date(Web):February 9, 2012
DOI:10.1021/ie202940k
Three kinds of iron-containing magnetic ionic liquids (ILs), including imidazole-based, pyridine-based, and pyrrolidine-based ILs, were synthesized respectively, and were used to dissolve coal direct liquefaction residues (CDLR) to obtain asphaltene fractions under the conditions of given time, temperature, and mass ratio of ILs to CDLR. The extracts from CDLR were characterized by ultimate analysis, proximate analysis, FT-IR, and 13C NMR. The results show that physicochemical properties of the extracts obtained with different magnetic ILs consisting of different cationic rings are different, and pyridine-based magnetic IL is an effective extractant to extract asphaltenes from CDLR among the three magnetic ILs. The extracts might be good precursors for preparing high-value-added carbon materials because of their higher carbon content, lower H/C, and ash content.
Co-reporter:Jieli Wang, Hongwei Yao, Yi Nie, Xiangping Zhang, Jianwei Li
Journal of Molecular Liquids 2012 Volume 169() pp:152-155
Publication Date(Web):May 2012
DOI:10.1016/j.molliq.2012.02.005
Three species of room temperature magnetic ionic liquids (ILs) including 1-butyl-3-methylimidazolium tetrachloroferrate ([bmim]FeCl4), N-butylpyridium tetrachloroferrate ([bPy]FeCl4) and 1-butyl-1-methylpyrrolidium tetrachloroferrate ([bmP]FeCl4) were synthesized via two-step in this paper. The intermediates and magnetic ILs were characterized by ultimate analysis, 1H NMR, ESI-MS, FT-IR and Raman. In addition, the three magnetic ILs were quantitatively tested by magnetic property measurement system (superconducting quantum interference device), and the results indicated that they had similar magnetic susceptibilities and paramagnetic properties. This research expanded cationic types of magnetic ILs, and supplied fundamental data to application of magnetic ILs.Magnetization of three species of room temperature magnetic ionic liquids [bmim]FeCl4, [bPy]FeCl4 and [bmP]FeCl4 were characterized by magnetic property measurement system (MPMS) as a function of temperature from 5 K to 300 K.Highlights► Two magnetic ionic liquids were first characterized with the same paramagnetism. ► Their magnetic susceptibilities are close to the imidazolyl magnetic ionic liquids. ► Their magnetic properties are tested in the 10,000 Oe magnetic field from 5 K to 300 k. ► This study provides references for synthesizing stronger magnetic ionic liquids.
Co-reporter:Hongwei Yao, Shuheng Zhang, Jieli Wang, Qing Zhou, Haifeng Dong, and Xiangping Zhang
Journal of Chemical & Engineering Data 2012 Volume 57(Issue 3) pp:875-881
Publication Date(Web):February 14, 2012
DOI:10.1021/je200922s
The densities and viscosities of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTf2]) + N-methyl-2-pyrrolidone (NMP) and [EMIM][NTf2] + ethanol mixtures were investigated over the mole fraction range from (0.1 to 0.9) and at temperatures from (293.15 to 323.15) K at intervals of 5 K. The densities can be well-represented by the quadratic equation, and the viscosities can be represented in the form of the Vogel equation. The excess molar volumes (VE) and viscosity deviations (Δη) were calculated, and the results were fitted to the Redlich–Kister equation using a multiparametric nonlinear regression method. The estimated parameters of the Redlich–Kister equation and standard deviation were also presented. The results showed that the densities and viscosities were dependent strongly on NMP or ethanol content. Comparatively, the viscosity deviation Δη was more sensitive to temperature than the excess molar volume VE.
Co-reporter:Yi Li, Xiangping Zhang, Shiyao Lai, Haifeng Dong, Xuelian Chen, Xiaoliang Wang, Yi Nie, Ying Sheng, Suojiang Zhang
Fuel 2012 Volume 94() pp:617-619
Publication Date(Web):April 2012
DOI:10.1016/j.fuel.2011.10.031
Some certain imidazolium ionic liquids (ILs) were attempted to extract valuable organic components in direct coal liquefaction residue (DCLR) and the possible mechanism involved in the extraction process of DCLR was proposed. The effective extraction was attributed to fracture of hydrogen bonds network in DCLR when the ILs dissolve DCLR. Moreover, the results showed that different IL solvents can extract various components. Thus, the selective extraction was realized and this provided a new pathway for extracting desired valuable components from DCLR.
Co-reporter:Yi Nie, Lu Bai, Yi Li, Haifeng Dong, Xiangping Zhang, and Suojiang Zhang
Industrial & Engineering Chemistry Research 2011 Volume 50(Issue 17) pp:10278-10282
Publication Date(Web):August 2, 2011
DOI:10.1021/ie201187m
Direct coal liquefaction residue (DCLR) contains about 25% asphaltenes which are proved to be important precursors for preparing high value-added carbon materials. In this work, ionic liquids (ILs) were used as potential solvents to extract asphaltenes from DCLR, and a series of dialkylphosphate ILs, i.e., imidazolium-based, pyridinium-based, and ammonium-based, were synthesized and used to extract asphaltenes from DCLR. The influences of extractive time, extractive temperature, and mass ratio of ILs to DCLR on extraction efficiency of asphaltenes were investigated and the optimized conditions were determined. In order to understand the mechanism of extraction asphaltenes with ILs, the extracts were characterized by elemental analysis, FT-IR, 13CNMR, and so on. The results show that it is feasible to extract asphaltenes from DCLR with dialkylphosphate ILs. The structure and size of anion and cation of ILs probably are the main factors that influence the extraction yield and the physicochemical characteristics of extracted asphaltenes, such as atomic ratio of H/C, the structure and aromatic cluster size, and so on.
Co-reporter:Yi Li, Xiangping Zhang, Heifeng Dong, Xiaoliang Wang, Yi Nie and Suojiang Zhang
RSC Advances 2011 vol. 1(Issue 8) pp:1579-1584
Publication Date(Web):25 Oct 2011
DOI:10.1039/C1RA00218J
A novel solvent mainly consisting of ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl) and N-methyl pyrrolidinone (NMP), was used to treat Direct Coal Liquefaction Residue (DCLR). The aim was to extract an important organic precursor compound from the DCLR as the raw material of carbon fibers. The performance of extraction and properties of the extract with the mixed solvent were analyzed and characterized by FT-IR, solid state 13C-NMR, DTA, micrograph and elemental analysis. The results showed that the mixed solvent was efficient to extract organic components from DCLR, but inert to inorganic substances. Adding NMP into [bmim]Cl not only accelerated the solid–liquid separation after the dissolution of DCLR, but also increased the extract yield. The possible synergistic mechanism was proposed based on the characteristic results. NMP in the mixture plays an important role to swell the fixed carbons contained in DCLR, and the ionic liquid [bmim]Cl contributes to destroying hydrogen bond forces in DCLR.
Co-reporter:X. Tian;X. Zhang;S. Zeng;Y. Xu;Y. Yao;Y. Chen;L. Huang;Y. Zhao;S. Zhang
Chemical Engineering & Technology 2011 Volume 34( Issue 6) pp:927-936
Publication Date(Web):
DOI:10.1002/ceat.201000426
Abstract
Using ionic liquid (IL) [C2MIM][PF6] as an additive could remarkably improve the performance of the acetonitrile (CAN) process, which is the most widely used distillation process to produce 1,3-butadiene (1,3-BT). In this work, a rigorous simulation of a new IL process to produce 1,3-BT was carried out to evaluate the performance of IL additive on an industrial scale, using UNIFAC as the global thermodynamic model. Based on the simulation models, some key operation parameters, such as solvent ratio and reflux ratio, were determined by sensitivity analysis. Furthermore, a multi-objective optimization was proposed and performed considering both the energy consumption and environmental impact (green degree) of the new process. A nonlinear mathematical model was established to express this multi-objective optimization problem, which includes six decision variables and involves maximizing the green degree of the process, the purity and the recovery of 1,3-BT, and minimizing the energy consumption of the process. The optimization results showed that the energy consumption of the IL-containing process could be reduced by 22 % and that its green degree could be improved by 9.2 %.
Co-reporter:Yansong Zhao, Xiangping Zhang, Haifeng Dong, Yingpeng Zhen, Guihua Li, Shaojuan Zeng, Suojiang Zhang
Fluid Phase Equilibria 2011 Volume 302(1–2) pp:60-64
Publication Date(Web):15 March 2011
DOI:10.1016/j.fluid.2010.08.017
Solubilities of CO, H2, N2, O2 and CO2 in novel alcamines ionic liquid (IL) of 2-[2-hydroxyethyl (methyl) amino] ethanol chloride ([MDEA][Cl]) were investigated at temperature ranging from 313.15 to 333.15 K and pressure ranging from 1.22 to 8.62 MPa. It was shown that the solubilities of gases increased with the increasing of pressure while decreased with the increasing of temperature. Comparing the solubilities of CO, H2, N2 and O2 with that of CO2 in [MDEA][Cl], it indicates that the solubilities of these four gases are much lower than that of CO2, which means [MDEA][Cl] may be used as a potential solvent for CO2 capture from mixed gases. The solublilities were correlated by the Krichevisky–Kasarnovsky equation and the Henry's constants and partial molar volumes of gases (infinitely diluted in pure [MDEA][Cl]) were obtained. Additionally, the standard Gibbs energy, standard enthalpy and standard entropy of gases (CO, H2, N2 and O2) were also calculated.
Co-reporter:Xiao Tian, Xiangping Zhang, Lu Wei, Shaojuan Zeng, Lei Huang and Suojiang Zhang
Green Chemistry 2010 vol. 12(Issue 7) pp:1263-1273
Publication Date(Web):14 Jun 2010
DOI:10.1039/B918924F
A multi-scale simulation method is proposed to enable screening of ionic liquids (ILs) as entrainers in extractive distillation. The 1,3-butadiene production process with acetonitrile (ACN) was chosen as a research case to validate the feasibility of the methodology. Ab initio calculations were first carried out to further understand the influence of ionic liquids on the selectivity of ACN and the solubility of C4 fractions in [CnMIM][PF6](n = 2–8), [C2MIM][X] (X = BF4−, Cl−, PF6−, Br−), by investigating the microstructure and intermolecular interaction in the mixture of C4 fractions and several selected ionic liquids. It was found that the selectivity of the ionic liquid is determined by both its polarity and hydrogen-bonding ability. Based on the analysis, a suitable ionic liquid was chosen. With the ab initio calculation, a priori prediction of thermophysical data of the IL-containing system was performed with COSMO-RS. The calculation revealed that the selectivity of the extractive solvent was increased by an average of 3.64% after adding [C2MIM][PF6]. With above calculations, an improved ACN extraction distillation process using ILs as an entrainer was proposed, and a configuration for the new process was constructed. Based on the established thermodynamic models which have considered the properties from the molecular structure of ILs, process simulation was performed to obtain the process parameters which are important for the new process design. The simulation results indicated that the temperatures at the bottom of the extractive distillation column with the ionic liquid as an additive are lowered by an average of 3.1 °C, which is significant for inhibition of polymerization. We show that the ACN consumption using this process can be lowered by 24%, and the energy consumption can likewise be lowered by 6.62%.
Co-reporter:Guihua Li, Qing Zhou, Xiangping Zhang, LeiWang, Suojiang Zhang, Jianwei Li
Fluid Phase Equilibria 2010 Volume 297(Issue 1) pp:34-39
Publication Date(Web):15 October 2010
DOI:10.1016/j.fluid.2010.06.005
Solubilities of ammonia in four conventional imidazolium ionic liquids: [Cnmim][BF4] (n = 2, 4, 6, 8) have been measured. Isothermally fixed temperatures are 293.15, 303.15, 313.15, 323.15 and 333.15 K; the pressure is from 0 to 1.0 MPa. High solubilities of ammonia are found, and it is also found that the solubilities of ammonia increase when the length of cations’ alkyl increases (the ILs have the same anion), that is: [C8mim]+ > [C6mim]+ > [C4mim]+ > [C2mim]+. The solubility data have been correlated by the Krichevisky–Kasarnovsky equation, and then Henry's constants and partial molar volumes of NH3 at infinite dilution are obtained. The thermodynamic properties such as solution enthalpy (ΔsolH), solution Gibbs free energy (ΔsolG), solution entropy (ΔsolS), and solution heat capacity (ΔsolCp) of these systems are obtained.
Co-reporter:Yansong Zhao, Xiangping Zhang, Shaojuan Zeng, Qing Zhou, Haifeng Dong, Xiao Tian, and Suojiang Zhang
Journal of Chemical & Engineering Data 2010 Volume 55(Issue 9) pp:3513-3519
Publication Date(Web):June 28, 2010
DOI:10.1021/je100078w
A series of novel ionic liquids, 2-aminoethanol tetrafluoroborate ([MEA][BF4]), 2-[2-hydroxyethyl(methyl)amino] ethanol tetrafluoroborate ([MDEA][BF4]), 2-[2-hydroxyethyl(methyl)amino] ethanol chloride ([MDEA][Cl]), 2-[2-hydroxyethyl(methyl)amino] ethanol phosphate ([MDEA][PO4]), and 2-[2-hydroxyethyl(methyl)amino] ethanol sulfate ([MDEA][SO4]), were synthesized and characterized for carbon dioxide capture in this work. Densities and viscosities of ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, [MEA][BF4], [MDEA][BF4], [MDEA][Cl], [MDEA][PO4], and [MDEA][SO4]), amines + ionic liquids + H2O, ionic liquids + H2O, and amines + H2O were measured at temperatures ranging from (303.15 to 343.15) K at different mass fractions. These 16 different absorbents were prepared by mixing two or three compounds of 2-aminoethanol (MEA), 2-[2-hydroxyethyl(methyl)amino] ethanol (MDEA), 2-[bis(2-hydroxyethyl)amino] ethanol (TEA), ionic liquids, and water. The carbon dioxide capture rate and carbon dioxide capture capacity in the 16 different absorbents were measured at 303.15 K and 1.50 MPa. The experimental results showed that the viscosities of these absorbents are less than 17.00 mPa·s at 303.15 K. Among these absorbents, the MDEA + [MDEA][Cl] + H2O + piperazine system shows the best performance on carbon dioxide capture.
Co-reporter:SuoJiang Zhang;YanSong Zhao;GuoYing Zhao
Science China Chemistry 2010 Volume 53( Issue 7) pp:1549-1553
Publication Date(Web):2010 July
DOI:10.1007/s11426-010-4030-z
A novel alkanolamine-based ionic liquid, N-methyl-diethanolammonium tetrafluoroborate ([MDEA][BF4]), was synthesized in our laboratory. The ionic liquid-based composite solution consisting of N-methyl-diethanolamine (MDEA), [MDEA][BF4], piperazine (PZ) and H2O was investigated for CO2 capture. The optimal performance for CO2 capture was found at 45 °C, 1.50 MPa, probably due to a synergistic action of the reaction and the transport. No apparent corrosion was found on stainless and carbon steel with the above composite solution. This finding is very significant to the promotion of its engineering application.
Co-reporter:Xiangping Zhang, Christian Solli, Edgar G. Hertwich, Xiao Tian and Suojiang Zhang
Industrial & Engineering Chemistry Research 2009 Volume 48(Issue 24) pp:10976
Publication Date(Web):November 9, 2009
DOI:10.1021/ie900199e
A flowsheet for the production of the substitutable transportation fuel dimethyl ether through biomass steam gasification to fuel (BSGtF) was constructed including heat integration. A quasi-equilibrium model was applied to simulate the whole process based on rigorous thermodynamic property prediction models. The carbon and hydrogen flows of the process showed that the atom utilization efficiency of carbon from the biomass to fuel process was 38.47%, and 39.75% of the total hydrogen was converted to the fuel product. The exergy flows of the total process and the exergy loss taking place in each process section were calculated based on the second law of thermodynamics. The results indicated that the total energy and exergy efficiencies from biomass to fuel were 51.3% and 43.5%, respectively, with a negative CO2 emission effect. The effects of gasification temperature, combustion temperature, and steam/biomass ratio on the gasification performance were investigated. The causes of exergy losses were analyzed to identify the areas of improvement so that a high energy utilization efficiency could be achieved.
Co-reporter:Liang Yu, Jing Lu, Xiangping Zhang, Suojiang Zhang
Fuel 2007 Volume 86(5–6) pp:722-734
Publication Date(Web):March–April 2007
DOI:10.1016/j.fuel.2006.09.008
A new numerical model based on the two-fluid model (TFM) including the kinetic theory of granular flow (KTGF) and complicated reactions has been developed to simulate coal gasification in a bubbling fluidized bed gasifier (BFBG). The collision between particles is described by KTGF. The coal gasification rates are determined by combining Arrhenius rate and diffusion rate for heterogeneous reactions or turbulent mixing rate for homogeneous reactions. The flow behaviors of gas and solid phases in the bed and freeboard can be predicted, which are not easy to be measured through the experiments. The calculated exit values of gas composition are agreed well with the experimental data. The relationship between gas composition profiles with the height of gasifier and the distributions of temperature, gas and solid velocity and solid volume fraction were discussed.
Co-reporter:Li Jiang, Yanyan Diao, Junxing Han, Ruiyi Yan, Xiangping Zhang, Suojiang Zhang
Chinese Journal of Chemical Engineering (October 2014) Volume 22(Issue 10) pp:1098-1104
Publication Date(Web):1 October 2014
DOI:10.1016/j.cjche.2014.08.002
Novel MgO–SBA-15 supported catalysts were prepared for oxidative esterification of methacrolein (MAL) with methanol to methyl methacrylate (MMA). The MgO–SBA-15 supports were synthesized with different magnesia loadings from different magnesium precursors and hydrochloric acid molar concentrations. The MgO–SBA-15 supports and Pd–Pb/MgO–SBA-15 catalysts were characterized by several analysis methods. The results revealed that the addition of MgO improved the ordered structure of SBA-15 supports and provided surface alkalinity of SBA-15 supports. The average size of the Pd3Pb particles on magnesia-modified Pd–Pb/MgO–SBA-15 catalysts was smaller than that on the pure silica-based Pd–Pb/SBA-15 catalysts. The experiments on catalyst performance showed that the magnesia-modified Pd–Pb/MgO–SBA-15 catalysts had higher activity than pure silica-based Pd–Pb/SBA-15 catalysts, showing the strong dependence of catalytic activity on the average size of active particles. The difference of activity between Pd–Pb/SBA-15 catalysts and Pd–Pb/MgO–SBA-15 catalysts was due to the discrepant structural properties and surface alkalinity provided by MgO, which led to the different Pd3Pb particle sizes and then resulted in the different number of active sites. Besides magnesia loadings, other factors, such as hydrochloric acid molar concentration and magnesium precursors, had considerable influences on the catalytic activity.Novel MgO–SBA-15 supported Pd–Pb catalysts were prepared for oxidative esterification of methacrolein (MAL) with methanol to methyl methacrylate (MMA). The synthesis conditions were investigated including magnesium precursors, magnesia loadings and hydrochloric acid molar concentration. The results show that the addition of MgO improves the ordered structure and provides surface alkalinity of SBA-15 supports, which decreases the Pd3Pb particle size and improves the catalytic activity. Under the optimal preparation conditions, 78.5% conversion of MAL together with 72.5% MMA selectivity was obtained. This new catalyst shows promising industrial application feasibility due to the high reaction efficiency and the ease of catalyst separation and recycling.Download full-size image
Co-reporter:Yajing Xu, Ying Huang, Bin Wu, Xiangping Zhang, Suojiang Zhang
Chinese Journal of Chemical Engineering (January 2015) Volume 23(Issue 1) pp:247-254
Publication Date(Web):1 January 2015
DOI:10.1016/j.cjche.2014.09.048
Biogas upgrading for removing CO2 and other trace components from raw biogas is a necessary step before the biogas to be used as a vehicle fuel or supplied to the natural gas grid. In this work, three technologies for biogas upgrading, i.e., pressured water scrubbing (PWS), monoethanolamine aqueous scrubbing (MAS) and ionic liquid scrubbing (ILS), are studied and assessed in terms of their energy consumption and environmental impacts with the process simulation and green degree method. A non-random-two-liquid and Henry's law property method for a CO2 separation system with ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) is established and verified with experimental data. The assessment results indicate that the specific energy consumption of ILS and PWS is almost the same and much less than that of MAS. High purity CO2 product can be obtained by MAS and ILS methods, whereas no pure CO2 is recovered with the PWS. For the environmental aspect, ILS has the highest green degree production value, while MAS and PWS produce serious environmental impacts.Upgrading process for removing CO2 from biogas is necessary. In this work, three upgrading technologies, i.e., pressured water scrubbing (PWS), monoethanolamine aqueous scrubbing (MAS) and ionic liquid scrubbing (ILS), are assessed. Process simulation and green degree method are adopted to evaluate the energy consumption and environmental impacts, respectively. Thermodynamic model is established for CO2 separation system with ionic liquid. The results indicate that the specific energy consumption of ILS and PWS is almost same but much lower than that of MAS. ILS presents the highest green degree production value, while MAS and PWS produce serious environmental impacts.Download full-size image
Co-reporter:Zhijun ZHAO, Haifeng DONG, Xiangping ZHANG
Chinese Journal of Chemical Engineering (February 2012) Volume 20(Issue 1) pp:120-129
Publication Date(Web):1 February 2012
DOI:10.1016/S1004-9541(12)60371-1
Due to their negligible volatility, reasonable thermal stability, strong dissolubility, wide liquid range and tunability of structure and property, ionic liquids have been regarded as emerging candidate reagents for CO2 capture from industries gases. In this review, the research progresses in CO2 capture using conventional ionic liquids, functionalized ionic liquids, supported ionic-liquids membranes, polymerized ionic liquids and mixtures of ionic liquids with some molecular solvents were investigated and reviewed. Discussion of relevant research fields was presented and the future developments were suggested.
Co-reporter:Zhenying MENG, Jian SUN, Jinquan WANG, Jianxin ZHANG, Zengzeng FU, Weiguo CHENG, Xiangping ZHANG
Chinese Journal of Chemical Engineering (December 2010) Volume 18(Issue 6) pp:962-966
Publication Date(Web):1 December 2010
DOI:10.1016/S1004-9541(09)60154-3
An ionic liquid system of [Bmim]X/[Bmim]OH (X = Cl, BF4, and PF6,) was developed for the hydrolysis of ethylene carbonate to ethylene glycol. The important parameters, such as the variety of ionic liquids, molar ratio of [Bmim]X to [Bmim]OH, amount of ionic liquid, molar ratio of water to ethylene carbonate, reaction temperature, pressure and reaction time, were investigated systematically. Excellent yield (>93%) and high selectivity (99.5%) of ethylene glycol were achieved. Under the optimum reaction conditions, the ionic liquid system could be reused at least five times and the selectivity of ethylene glycol remained higher than 99.5%.
