INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
·
IF 6.953
Xiaotong Fu,Fulong Zhang,Cuihua Dong,Wenyuan Zhu,Kaifeng Xiong,Zhiqiang Pang
An appropriate cellulose-dissolving solvent is critical for the homogeneous oxidation of cellulose using TEMPO (2, 2, 6, 6-tetramethylpiperidine-1-oxyl)-mediated system. Herein, TEMPO/NaClO/NaClO 2 system in lithium bromide hydrates (LBHs) was developed for the homogeneous selective-oxidation of cellulose, which was two-stage protocol involving cellulose dissolution and homogeneous oxidation. Specifically, cellulose was firstly dissolved in LiBr·3.5H 2 O and offered the optimal pH (5.6) for the subsequent TEMPO/NaClO/NaClO 2 oxidation without precipitation of the cellulose chains. Effect of reaction conditions on cellulose oxidation was investigated. The results showed that high degree of oxidation (DO) and evenly distributed carboxyl could be achieved. The particle size gradually decreased with DO, and oxidized cellulose with high water solubility and amorphous structure could be obtained. Furthermore, FT-IR, 13 C NMR and fractionation analysis verified that cellulose was successfully converted and the carboxyl uniformly distributed onto the cellulose chains. This TEMPO-mediated system using LBHs as solvent presented an efficient method on the homogeneous selective oxidation of primary hydroxyl in cellulose.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Processes
·
2022
·Vol. 10
·期 5
·823
·
IF 3.352
Bin Li,Xinjun Jing,Junsheng Yuan
The phase equilibria of the reciprocal quaternary system LiBr-Li2SO4-KBr-K2SO4-H2O and its ternary sub-systems LiBr-Li2SO4-H2O and KBr-K2SO4-H2O at 308.15 K were studied using the isothermal dissolution equilibrium method. Then, the solubility data of the equilibrium solutions were collected, and the phase diagrams were plotted. The phase diagrams of the ternary sub-systems at 308.15 K were compared with those at other temperatures. This study found that the phase diagram of the LiBr-Li2SO4-H2O system at 308.15 K consisted of an invariant point, two solid-phase crystallization regions of Li2SO4·H2O and LiBr·2H2O, and their corresponding solubility curves. The system generated two hydrated salts, which belonged to the hydrate type I phase diagram. The phase diagram of the KBr-K2SO4-H2O system at 308.15 K consisted of an invariant point, two univariant solubility curves, and two solid-phase crystallization regions of KBr and K2SO4, and no solid solution and double salts were formed. Thus, it belonged to a simple co-saturation type phase diagram. In the LiBr-Li2SO4-KBr-K2SO4-H2O system, K2SO4·Li2SO4double salt formed at 308.15 K, and the phase diagram consisted of three invariant points, five crystallization regions, and seven univariant solubility curves.Keywords:lithium bromide;potassium bromide;lithium sulfate;potassium sulfate;phase equilibrium
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2023
·
IF 5.5
Cui Ruizhi,Peng Changwei,Nie Guoliang,Sang Shihua,Ren Hongbao,Li Wu
In view of the composition characteristics of lithium, calcium and bromine rich in Nanyishan oil and gas field brine of western Qaidam Basin, Qinghai Province, as well as based on the results reported in relevant literature, the phase equilibrium relationship of ternary system LiBr-CaBr2-H2O at 298.15 K was studied by isothermal dissolution equilibrium method. The equilibrium solid phase crystallization regions, as well as the compositions of invariant point, in phase diagram of this ternary system were clarified. On basis of the above ternary system research, the stable phase equilibria of quaternary systems (LiBr-NaBr-CaBr2-H2O, LiBr-KBr-CaBr2-H2O and LiBr-MgBr2-CaBr2-H2O), as well as quinary systems (LiBr-NaBr-KBr-CaBr2-H2O, LiBr-NaBr-MgBr2-CaBr2-H2O and LiBr-KBr-MgBr2-CaBr2-H2O) were further carried out at 298.15 K. According to the above experimental results, the corresponding phase diagrams at 298.15 K were drawn, which revealed the phase relationship of each component in solution and the law of crystallization and dissolution, and meanwhile summarized changing trends. The research results of this paper lay a foundation for further research on the multitemperature phase equilibria and thermodynamic properties of lithium and bromine containing high-component brine system in later stage, and also provide basic thermodynamic data for guiding the comprehensive development and utilization of this oil and gas field brine resource.
研究领域:
化学
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热力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
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2025
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IF 4.3
Zixi Wu,Chunxiang Huang,Leyi Li,Jinxiang Cao,Yingjie Liu,Qing Ye,Jinlong Li
The paper presents experimentally determined solubility results of lithium bromide in ionic liquid + water and assesses the effect of the addition of ionic liquids (ILs) on the solubility of lithium bromide (LiBr) in water. The solubility of LiBr in pure water has been determined and compared to the literature data. It is known that LiBr aqueous solutions are widely used as working fluids in low-temperature thermal energy recovery systems. However, the aqueous LiBr solution is easy to crystallize, which could cause equipment corrosion. One of the possibilities for improving the properties of the H2O/LiBr refrigerant system is the use of an additive to increase the solubility of LiBr in water. Three ILs were selected as an additive: 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]), 1-ethyl-3-methylimidazolium bromide ([EMIM]Br), and 1-butyl-3-methylimidazolium bromide ([BMIM]Br). In this study, new empirical parameters for the calculation of LiBr solubility in water were provided. A reasonable prediction of phase equilibrium data is made using the COSMO-SAC model. The NRTL equation is also calculated. The maximum deviation of COSMO-SAC is 7.56%, and the deviation of the other calculations is less than 2%. These experimental and theoretical findings offer valuable insights into the selection and optimization of working fluids in absorption cycle systems.
研究领域:
化学工程
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热力学
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材料科学
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物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2020
·Vol. 36
·期 6
·1234-1240
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IF 1.063
Cui Ruizhi,Li Wu,Dong Yaping,Li Jun
The stable phase equilibria of quaternary systems LiBr-NaBr-MgBr 2 -H 2 O and LiBr-KBr-MgBr 2 -H 2 O at 298.15 K were studied by both experimental measurement(isothermal solution saturation method) and theoretical prediction(Pitzer model). The solubilities of the saturated solution have been determined experimentally and two stable phase diagrams and relevant water diagrams of the two quaternary systems were obtained. Results show that quaternary system LiBr-NaBr-MgBr 2 -H 2 O is hydrate II type as NaBr and NaBr·2H 2 O coexistence. Its phase diagram consists of only one invariant point, four univariant curves, and five crystallization fields. The quaternary system LiBr-KBr-MgBr 2 -H 2 O is a complex type as the double salt KBr·MgBr 2 ·6H 2 O formed. In addition to this double salt, the three single salts LiBr·2H 2 O, KBr and MgBr 2 ·6H 2 O also crystallize. In this paper, the solubilities of phase equilibria in above quaternary systems were also calculated by the Pitzer’s electrolyte solution model. All the needed parameters can be obtained from the literature or be fitted by experimental data. On the Basis of the experimental and calculated results, the phase diagram of the quaternary system was plotted for comparison. It shows that the calculation results are consistent with the experimental ones.
研究领域:
化学热力学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2022
·
IF 3.119
Guo-Liang Nie,Rui-Zhi Cui,Wu Li
According to the composition characteristics of lithium, potassium, bromine, and other resources rich in the salt lake brine of the Qinghai–Tibet Plateau, the phase equilibria of the quaternary system LiBr-NaBr-KBr-H2O and its ternary subsystem LiBr-KBr-H2O at 323.15 K are studied by an isothermal dissolution equilibrium method. The solubility of each system in equilibrium solution at the corresponding temperature is measured, and the corresponding phase diagrams are drawn according to the phase equilibrium experimental data. The results show that there is no complex salt or solid solution in the ternary system LiBr-KBr-H2O at 323.15 K. The phase diagram contains one invariant point (E1), two univariate curves (AE1 and BE1), and two equilibrium solid crystallization regions (corresponding to LiBr·H2O and KBr), belonging to the simple cosaturated type. The quaternary system LiBr-NaBr-KBr-H2O also has no formation of complex salt and solid solution. The phase diagram contains two invariant points (F1 and F2), five univariate curves (E1F1, E3F1, F1F2, E2F2, and E4F2), and four equilibrium solid-phase crystallization regions (corresponding to LiBr·H2O, KBr, NaBr·2H2O, and NaBr). At the same time, to further explain the phase equilibrium relationship of each system at different temperatures and the change rule of each component, comparison and discussion are carried out.
研究领域:
化学工程
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材料科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Tianyuan Xiao,Jiahui Song,Wenchao Jia,Yanning Sun,Yanzhu Guo,Pedram Fatehi,Haiqiang Shi
The chemical bond cleavage of lignin is a research focus for achieving depolymerized lignin for such applications as adhesives, fuels, fertilizers, etc. The depolymerization of an industrially available sustainable material, i.e., industrial alkali lignin, in LiBr·3H 2 O/HBr-γ-valerolactone (GVL) was systematically investigated in this study. It was observed that using 3/1 mL/g of HBr/lignin and 8/1 mL/g of GVL/lignin at 110 °C for 90 min, i.e., optimized conditions, resulted in lignin derivatives with an M w of 1889 g/mol and M n of 895 g/mol. The characteristics of the products were studied using FTIR, NMR, SEM, and DLS techniques. The results confirmed that the Hibbert-ketone end group was formed, while the structure of the aromatic ring was not changed on the depolymerized lignin. After the depolymerization process, the hydroxyl content in lignin increased from 1.91 mmol/g to 2.96 mmol/g. The product derived from the LiBr·3H 2 O/HBr-GVL depolymerization system displayed a spherical particle morphology. The addition of GVL to lignin depolymerization processes improved the bonding between lignin and inorganic molten salts, thereby promoting the acid-catalyzed cleavage of aryl ether bonds in lignin. Current research supports the conclusion that LiBr·3H 2 O/HBr-GVL lignin depolymerization is a sustainable and effective chemical pathway for generating depolymerized lignin.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Yi-Feng Wang,Li-Na Song,Fei Li,Yue Wang,Xiao-Xue Wang,Ma-Lin Li,Lian-Chun Zou,Ji-Jing Xu
High concentration LiBr is beneficial to enhance the Br − oxidation rate, displaying stable low voltage plateau during charging process for lithium–oxygen batteries . However, the sufficient cyclic performance is generally restricted by uncontrollable high level Br 3 − , resulting in the low energy efficiency and shuttle effect . Herein, a nanoreactor , red-ox mediators shuttling suppressor and lithium-metal protector with the combination of the high concentration and shuttle-free LiBr are successfully constructed by anchoring the Br 3 − to carbonized ZIF-8 supported on reduced graphene oxide substrate (ZC-rGO). ZnO-decorated/nitrogen-doped 3D carbon framework of ZC-rGO cathode can accurately capture Br 3 − by space confinement effects and/or chemisorption , which is beneficial to improve the oxidation of discharge products (Li 2 O 2 ) and avoid the anode corrosion. The Li–O 2 battery demonstrates enormous advantages of the RMs in comparation with the typical rGO-based batteries, such as better cycling performance (>90 cycles) and more stable overpotential (<1.0 V). The proposed strategy in this study opens up a new way of inhibiting the shuttle effect of RMs in Li–O 2 batteries and other halogen batteries.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2019
·
IF 5.537
Wang Pei,Qing Cheng,Shun Jiao,Lin Liu
In this paper, an electrodialysis regeneration experimental system was set up to evaluate the performance of electrodialysis regeneration system using lithium bromide solution, whose concentration is much higher than that of LiCl solution. The effects of cycling flow rate, initial concentration, and operating current on the current efficiency of the electrodialysis regeneration system using LiBr solution were studied. The current efficiency model and regeneration result model of the electrodialysis regenerator for LiBr solution were acquired based on experimental results. The results show that the ED regenerator can regenerate the LiBr solution reliably, and the current efficiency of the ED regenerator using LiBr solution is lower than that for LiCl solution. To enhance the capability of electrodialysis regenerator, the difference in cycling flow rates between dilute and concentrate chambers should be controlled. The current efficiency of the electrodialysis regenerator and COP of electrodialysis regeneration system decreased with the increase of the operating current and initial concentration. When the concentration of LiBr solution is 45% and the operating current is 3A, the electrodialysis regeneration system has the maximum current efficiency of about 30.365% and the maximum COP of 4.26.
研究领域:
能源工程
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环境工程
✓ 已验证
DOI
高影响因子
International Journal of Refrigeration
·
2017
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IF 2.779
Zhong Lan,Xuehu Ma,Zhaolong Hao,Rui Jiang
This work mainly focuses on the determination of the saturated vapor pressure of LiBr aqueous solution with mass fraction ranging from 43.14 to 65.26 wt% at high temperature experimentally. First, the measurement of the saturation vapor pressures is conducted in deionized water as well as in LiBr aqueous solution at a lower temperature. The experimental result has a good agreement with the literature value, which verified the reliability and accuracy of the experimental apparatus. Second, measurement of the saturated vapor pressure of LiBr aqueous solution with mass fraction ranging from 43.14 to 65.26 wt% is systematically carried out in the 156.06~257.84 °C temperature range. Based on the saturated vapor pressure data at lower temperature, a correlation for predicting the saturated vapor pressure data of the LiBr aqueous solution is obtained, which is also available for high temperature condition. Therefore, this work will be very helpful for the modeling and design of high temperature LiBr/H 2 O absorption heat transformers.
研究领域:
化学工程
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热力学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Mizeng Wang,Qiyu Liu,Xueqing Qiu,Run Tang,Zihan Zhang,Qiaozhi Ma
Glucan oligomers are unique chemicals with versatile value-added applications in agriculture and healthcare depending on their specific glycosidic linkages. Glucose glycosylation shows high efficiency in glucan oligomer production, but the formed glycosidic bonds are generally random, which limits its application. To address this issue, we employed an unacidified molten salt hydrate (MSH) of LiBr·3.2H2O as the reaction medium and glucose/disaccharides as the substrate. Results showed that a 66.6% yield of glucan oligomer can be produced from glucose with a high selectivity of 93.2%, suggesting limited byproduct degradation. When maltose was used as the substrate, the initial α(1 → 4) glycosidic bonds were well preserved. Maltose was effectively converted into an α-type glucan oligomer consisting of 79.9% α(1 → 4) and 20.1% α(1 → 6) glycosidic linkages. The kinetic analysis revealed that the α(1 → 4) bond has a high activation energy of 57.9 kJ/mol, ensuring its chemical stability in unacidified LiBr·3.2H2O conversion. The unacidified MSH reaction medium presents a possibility of enhanced and structure-tunable glucan oligomer production via a glycosylation method.
研究领域:
生物化学
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食品科学
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农业科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Zhilin Shen,Yingling Fang,Bihe Yuan
The widespread use of flammable building materials severely threatens residential safety. Additionally, traditional fire-alarm systems may fail in complex fire environments due to power disruptions. It is crucial to enhance the flame retardancy of material while establishing effective fire detection and early warning systems. This study prepared a chitosan/gelatin (CG) and LiBr-modified CG (CG-LiBr) composite film using an environmentally friendly water evaporation method. We coated the CG-LiBr film with polytetrafluoroethylene (PTFE), thus a flame-retardant and conductive PTFE-coated film-based triboelectric nanogenerator (PF-TENG) was developed. Notably, the CG-LiBr film exhibits outstanding alarm capabilities, with response times of 0.41 s at 100 °C and 0.4 s under flame attack. Compared to the initial CG, CG-LiBr shows a 24.4 % increase in char residue and a 62.1 % reduction in peak heat release rate. Furthermore, PF-TENG demonstrates excellent voltage output, achieving up to 60.8 V at a vertical contact-separation frequency of 5 Hz. Integrating CG-LiBr's exceptional dual-alarm function into fire protection suits and building materials, along with the development of a fire-alarm system featuring remote signal transmission capabilities, holds considerable promise for enhancing fire safety and developing intelligent early warning systems.
研究领域:
材料科学
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消防安全
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生物材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）