科创中国

This paper presents a flexible model and a robust algorithm for simulation of multi-stage multi-component separation processes in which multiple feeds, side streams, strippers and/or side heat exchangers are involved. The improved algorithm effectively accelerates the speed of convergence and offers better stability by introducing a damping factor for updating the stripping factor, and also reduces the requirement on the initial estimates by updating the Joacobian matrix directly with the stripping factor and enthalpy. On the other hand, an efficient algorithm was proposed to solve the approximate tri-diagonal matrix (containing the off-band elements) derived from the material balance equations (M equations) and phase equilibrium equations (E equations), the advantages and simplicity of the 'inside-out' technique of the Russell are retained. The present algorithm was demonstrated to be effective in simulating complex separation columns with typical case studies.

Chun Shan Li;香平 张;锁江 张;Xin Shun Tan;Shu Guang Xiang

Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering

2006-4

Jian Sun;Weiguo Cheng;Jinquan Wang;Junping Zhang;锁江 张

2013

Vapor-liquid equilibria in the binary systems of methacrolein and methanol with l-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF₄) were determined at 350.75, 341.55 and 331.55 K in this work. The non-random tow-liquid equation was applied to correlate the experimental data. The results showed that the solubility of methacrolein in [BMIM]BF₄ decreased with temperature increasing and increased with pressure increasing, and the solubility of methanol in [BMIM]BF₄ had the similar phenomenon. Compared with ideal solution, the system of methacrolein with [BMIM]BF₄ showed positive deviation, and the system of methanol with [BMIM]BF₄ showed negative deviation. The correlated results with non-random tow-liquid model were in good agreement with the experimental data. The average relative deviation of methacrolein and [BMIM]BF₄ system was 1.20%, and that of methanol and [BMIM]BF₄ system 0.42%.

Qiong Chen;Rui Yi Yan;Xiao Liang Yuan;锁江 张

Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering

2008-1

Fuel cells and metal-air batteries will only become widely available in everyday life when the expensive platinum-based electrocatalysts used for the oxygen reduction reactions are replaced by other efficient, low-cost and stable catalysts. We report here the use of nitrogen-doped graphdiyne as a metal-free electrode with a comparable electrocatalytic activity to commercial Pt/C catalysts for the oxygen reduction reaction in alkaline fuel cells. Nitrogen-doped graphdiyne has a better stability and increased tolerance to the cross-over effect than conventional Pt/C catalysts. This journal is

Rongji Liu;Huibiao Liu;玉良 李;Yuanping Yi;Xinke Shang;Shuangshuang Zhang;Xuelian Yu;锁江 张;Hongbin Cao;Guangjin Zhang

Nanoscale

2014-10-7

This work presents a study to apply ionic liquids as potential industrial solvents for carbon dioxide capture. In order to obtain effective and low cost ionic liquids solvents, novel alcamines ionic liquids of 2-aminoethanol tetrafluoroborate, 2-[2-hydroxyethyl (methyl) amino] ethanol tetrafluoroborate, 2-[2-hydroxyethyl (methyl) amino] ethanol phosphate, 2-[2-hydroxyethyl (methyl) amino] ethanol sulfate and 2-[2-hydroxyethyl (methyl) amino] ethanol chloride were synthesized and characterized. Ten ionic liquids solvents of amines+ionic liquids+H₂O, ionic liquids+H₂O were prepared by mixing two or three compounds of 2-aminoethanol, 2-[2-hydroxyethyl (methyl) amino] ethanol, 2-[bis (2-hydroxyethyl) amino] ethanol, ionic liquids and water to capture carbon dioxide. Additionally, CO₂ capture performances in three traditional amines+H₂O solvents were also investigated. The results show that 2-[2-hydroxyethyl (methyl) amino] ethanol+2-[2-hydroxyethyl (methyl) amino] ethanol chloride+H₂O+piperazine (MCHP) system is the best among the prepared solvents. The regeneration performance of the solvent was also investigated. Mechanisms of CO₂ absorption and desorption with the synthesized ILs are obtained by in situ FTIR spectra analysis.

Yansong Zhao;香平 张;Yingpeng Zhen;Haifeng Dong;Guoying Zhao;Shaojuan Zeng;Xiao Tian;锁江 张

International Journal of Greenhouse Gas Control

2011-3

In this work, the alkylation of isobutane and butene, catalyzed by sulfuric acid in the presence of the fluoride–containing ionic liquids [Bmim][PF₆] and [Bmim][SbF₆], was investigated. The use of the binary mixture catalysts brought to a higher C₈ selectivity and longer catalyst lifetime, compared with the results obtained when working with sulfuric acid only. This was attributed to the formation of new species when [Bmim][PF₆] or [Bmim][SbF₆] are added to sulfuric acid. The acidolysis of [Bmim][PF₆] and [Bmim][SbF₆] was accompanied by the release of hydrogen fluoride (HF) and the decomposition of anions to [PF_6−x−2y(HSO₄)_x(SO₄)_y]⁻ and [SbF_6−x−2y(HSO₄)_x(SO₄)_y]⁻, respectively. The presence of these new species after acidolysis was measured and confirmed by ion chromatography, ¹H–Nuclear Magnetic Resonance (NMR), ¹⁹F–NMR and ³¹P–NMR. The production of HF and the complexation of anions and carbenium ions both play an important role in stabilizing the carbenium ion and improving the catalytic performance.

Honghua Zhang;Ruixia Liu;Zhiqiang Yang;Feng Huo;Ruirui Zhang;Zihang Li;锁江 张;延吉 王

Fuel

2018

The ability to suppress the formation and proliferation of lithium dendrites is an important endeavour towards the successful commercialization of lithium metal batteries as high energy storage devices. The use of gel polymer electrolytes is one of the most promising pathways to solving this problem and obtaining high performance. Here, we propose a novel gel polymer electrolyte (GPE), in which a nanostructured ionic liquid (IL), silica nanoparticle-tethered 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide (SiO₂PPTFSI), is first introduced into a gel polymer electrolyte matrix based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) prepared by electrospinning, followed by plasticization in a fluoroethylene carbonate (FEC) electrolyte. After being incorporated with the nanostructured IL, this novel GPE exhibits good mechanical properties, an enhanced electrolyte uptake (552 wt%) and a high ionic conductivity (0.64 mS cm^-1) and lithium ion transference number (tLi⁺ = 0.60). In addition, it suppresses lithium dendrite formation and exhibits stable plating/striping cycles over 1200 hours in a symmetric lithium cell. More importantly, it is electrochemically stable up to 5.1 V (vs. Li/Li⁺), making it practical for use in LiNi_0.5Mn_1.5O₄ systems with a much better cycle stability and rate capability relative to those of Celgard with a liquid electrolyte or GPE based on PVDF-HFP. The Li/LiNi_0.5Mn_1.5O₄ cell with the novel GPE exhibits an initial discharge capacity of 119 mA h g^-1 at 1C, a capacity retention of 92.1% after 460 cycles, and a high reversible capacity of 74 mA h g^-1 at 6C. Therefore, the use of a nanostructured IL-modified GPE presents a promising way to enhance the cycle performance and safety of lithium metal cells.

Yuanyuan Cheng;Lan Zhang;Song Xu;Haitao Zhang;保增 任;Tao Li;锁江 张

Journal of Materials Chemistry A

2018

Because of the sluggish dynamic and complex electrostatic potential networks of ionic liquids, establishing a reasonable and efficient coarse-grained model with enough simulation time is very important for a large system. In this work, novel coarse-grained models of 1-n-alkyl-3-methylimidazolium chloride [C_nmim][Cl] (n = 4, 6, 8) have been developed from the united atom model of ionic liquids. There are two mapping strategies for the ionic liquids coarse graining, one is that the imidazolium cations ([C_nmim]⁺ (4, 6, 8)) and Cl^- anion are represented as single coarse-grained bead as an ionic model. The other is a pair of ionic liquids mapped to one bead as a molecular model. It was found that both of the coarse-grained models could give a good description of structures and thermodynamic properties for ionic liquids. Moreover, because of the reducing freedom of a coarse-grained model a correction of the results as a united atom force field was established for self-diffusion coefficients which could be reproduced effectively. Notably, the ionic model improves the calculation efficiency up to 9.5 times compared with united atom force field under the same simulation conditions because the electrostatic potentials in the ionic model are highly important for coarse-grained model for ionic liquids. In summary, the coarse-grained models could provide a theoretical basis for large-scale ionic liquids systems.

Jiahuan Tong;Yandong Guo;Feng Huo;Xiaodong Xie;Hongyan He;Nicolas Von Solms;Xiaodong Liang;锁江 张

Industrial & Engineering Chemistry Research

2018-11-7

Layered HNb₃O₈/graphene hybrids with numerous heterogeneous interfaces and hierarchical pores were fabricated via the reorganization of exfoliated HNb₃O₈ nanosheets with graphene nanosheets (GNs). Numerous interfaces and pores were created by the alternative stacking of HNb₃O₈ nanosheets with limited size and GNs with a buckling and folding feature. The photocatalytic conversation of CO₂ into renewable fuels by optimized HNb₃O₈/G hybrids yields 8.0-fold improvements in CO evolution amounts than that of commercial P25 and 8.6-fold improvements than that of HNb₃O₈ bulk powders. The investigation on the relationships between microstructures and improved photocatalytic performance demonstrates that the improved photocatalytic performance is attributed to the exotic synergistic effects via the combination of enhanced specific BET surface area, increased strong acid sites and strong acid amounts, narrowed band gap energy, depressed electron-hole recombination rate, and heterogeneous interfaces.

He Liu;Haitao Zhang;Peng Shen;Feixiong Chen;锁江 张

Langmuir

2016-1-12

Research progress in application of CO₂ fixation and transformation using ionic liquids (ILs) has been systematically discussed. There are three kinds of CO₂ fixation using ILs according to structures of ionic liquids and mechanism of fixation, which are CO₂ fixation using common ILs, CO₂ fixation using task-specific ILs and fixation-conversion of CO₂ using ILs. The mechanism of CO₂ fixation using common ionic liquids is physical absorption and that of task-specific ILs is chemical process, while fixation and conversion of CO₂ using ILs will be a good way from flue gas to new chemicals. Design and synthesis of high effective task-specific ILs to achieve the goal of fixation and conversion of CO₂ will be a key step applied in CO₂ fixation.

Xiao Liang Yuan;Yan Qiang Zhang;Ling Lan;锁江 张

Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering

2008-4