Arabian Journal of Chemistry
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2023
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IF 6
Lan Yi,Xiaoqin Wu,Shuguang Ouyang,Li Guo,Jialing Chen,Mario Gauthier,Wen-Ying Li
The extraction of indole from wash oil is of economic value and practical significance. In this study, deep eutectic solvents (DESs) are investigated to extract indole from wash oil. Initially, density functional theory calculations were used to explore the association of indole with aromatic compounds in wash oil, and the feasibility of indole extraction with a tetraethylammonium chloride/ p -toluenesulfonic acid (TEAC/2TsOH) DES. Then, the influence of the temperature, stirring time, DESs dose, initial indole concentration, and amount of water added were investigated, followed by discussions on the comparison with other extractants and the performance of extracting of indole from real wash oil. The results show that indole associates with aromatic compounds in wash oil through π−π interactions, but that a large electrostatic interaction energy of −52.8 kJ/mol between indole and the DESs is the main driving force for the extraction process. Under optimal conditions, TEAC/2TsOH extracts more than 63.5 ± 3% of indole from wash oil, and its extraction capacity is superior to other extractants.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2020
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IF 4.982
Xin Jin,Xiaorong Li,Jiao Kong,Wei Xie,Meijun Wang,Jiancheng Wang,Weiren Bao,Liping Chang
The high yields of coke and tar pitch relating to volatile reactions can cause plug in the product lines during low temperature pyrolysis of low-rank coals. To study the potential transformation of volatile into coke during its migration in the pyrolysis process, six distillates and their blends from the same coal tar were heated at 400–600 °C. The composition , radicals of six distillates and coke structure were characterized by GC × GC–MS, ESR and Raman techniques, respectively. The results show that the coke yields increase with temperature during thermal reaction for all six distillates. When light oil and pitch are blended, the interaction between the two distillates compresses the transformation of volatile into coke above 500 °C. This can be ascribed to that the reactive hydrogen radicals generated from light oil may weaken the bonding between large molecules. By contrast, other distillates (phenolic oil, naphthalic oil, wash oil and anthracene oil) promote coke formation, resulting in higher coke yields than expected. It is also observed that the highest extent of interaction occurs between phenolic oil and pitch, which may be related to the high content of oxygen containing compounds in phenolic oil and the high electron density of the compounds in pitch.
研究领域:
化学工程
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能源科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Xudong Zhang,Junyao Wang,Jun Shen,Yugao Wang,Gang Liu,Yanxia Niu,Qingtao Sheng
Indole is an important organic synthesis intermediate derived from the wash oil fraction in coal tar. Deep eutectic solvents (DESs) have been widely used in the separation field due to their unique properties such as easy preparation, low cost, green and high extraction efficiency, and reusability. In this study, five DESs, including tetramethylammonium chloride/ethylene glycol (TMAC/EG), triethylmethylammonium chloride/ethylene glycol (TEMAC/EG), tetraethylammonium chloride/ ethylene glycol (TEAC/EG), tetrapropylammonium chloride/ethylene glycol (TPAC/EG), tetrabutylammonium chloride /ethylene glycol (TBAC/EG) were prepared and used to extract indole from model wash oil. The results showed that TPAC/EG exhibited the best extraction ability under the same conditions. Then, the main experimental parameters such as mass ratio of DES to model wash oil, extraction temperature, extraction time, standing time and initial concentration of indole, were investigated when using TPAC/EG as extractant. In optimal conditions (25℃, 5 min, mass ratio 1:8), the extraction efficiency, selectivity and distribution coefficient for indole were 90.51%, 79.21% and 61.12, respectively. Moreover, removing neutral oil with petroleum ether, the purity of indole further reached 96.63%, which was much higher than that in the previous studies reported. In addition, accessible and environmentally friendly water instead of diethyl ether was used to regenerate the DES. Reused four times, the TPAC/EG extraction ability for indole almost did not change. Finally, the mechanism of extraction process was investigated by FT-IR analysis. This work provides a new route for extraction and recovery indole from wash oil.
研究领域:
化学工程
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环境科学
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有机化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Youan Ji,Yucui Hou,Shuhang Ren,Weize Wu
Indole is an important chemical that can be directly obtained from wash oil mixtures. In this work, several tetraethyl ammonium amino acid (TAAA) ionic liquids (ILs) were designed to separate indole from model wash oil through forming hydrogen bonds. The effects of important factors, such as stirring time, TAAA type, indole concentration, temperature, and TAAA:indole mole ratio, on indole separation were investigated. It is found that these TAAAs can separate indole from model wash oil with separation efficacy up to 98.0% (for tetraethylammonium L-alanine ionic liquid), and the ultimate indole concentration is 1.6 g/dm 3 . This separation process takes less than 5 min. Also, for one kind of TAAA, the ultimate indole concentrations are almost constant despite different initial indole concentrations. The maximum distribution coefficients of indole are 200.9 at the studied conditions. We have also found that water content in TAAA shows a negative effect on indole separation, which inspired us to design a process for TAAA regeneration using water. After regeneration, TAAA can be reused, and the separation efficacy of indole is not significantly reduced. The FT-IR results show that there are hydrogen bonds between TAAAs and indole. Finally, we compared the TAAA method to other methods and demonstrated the advantages.
研究领域:
化学工程
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分析化学
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材料科学
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Yingpeng Chen,Jie Cao,Ying Li,Hongbo Zeng
As the challenge of enhancing oil recovery from reservoirs continues to grow, it becomes increasingly crucial to seek out new materials for oil displacement. Janus graphene oxide (JGO) with excellent interfacial activity stands out as a promising candidate, which enables it to locate crude oil and effectively displace it towards production wells. One key advantage of JGO is its ability to reduce interfacial tension and create interfacial films, attributed to JGO nanosheets adsorbing at oil–water interfaces. Another noteworthy property of JGO is its capacity to transform oil-wet rock surfaces into water-wet surfaces, which is because JGO nanosheets can interact hydrophobically with crude oil molecules on rock surfaces. In addition, JGO helps mitigate capillary resistance by altering the concave oil–water front to a flat state. Microscopic displacement shows that JGO nanosheets enlarge the sweep efficiency and oil-washing efficiency of water. Nuclear magnetic resonance experiment indicates that JGO nanofluid can increase oil recovery by 17.1 %. This research presents a comprehensive exploration of the interfacial activity of Janus nanofluid, spanning from the molecular scale to the micro and core scales.
研究领域:
材料科学
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石油工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子