Metals
·
2025
·Vol. 15
·期 5
·468
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IF 2.5
Shuo Tian,Jing Song,Hongqian Sun,Congcong Zhao,Zhiyu Zhang,Mingming Han,Tao Qi
Zirconium (Zr) and hafnium (Hf) are very important in nuclear and high-temperature applications, but their similar physical and chemical properties bring great challenges to separation. The current extraction methods have defects, such as low efficiency at high metal concentration. In this article, a zirconium (Zr)/hafnium (Hf) solvent extractive separation from sulfuric acid solutions using trioctylamine (TOA) as the extractant was researched at room temperature. The aqueous solution is prepared using zirconium sulfate (containing Hf), and the concentration of metal ions (Zr4+and Hf4+) was about 1.096 mol·L−1. The effects of the aqueous acidity, the concentration of TOA, the contacting time, and the organic to aqueous O/A ratio on the separation of Zr and Hf were investigated. It is observed that the Zr can be extracted in the organic phase selectively, and the optimal conditions were: TOA concentration of 40 vol%, organic to aqueous O/A ratio of 3, contacting time of 5 min. Under these conditions, the single-stage extraction rate of Zr is 61.23%, while the Hf is almost not extracted. The mechanism of Zr extraction by TOA was studied through the saturation capacity and slope methods. Based on the results, it is believed that the structure of the extracted complex may be [R3NH]2[Zr(SO4)3]. This study provides a new approach for the development of industrialized Zr-Hf separation.
研究领域:
化学工程
·
核工业
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2013
·
IF 2.297
Sheng Fang,Xiao-Bo Zuo,Xue-Jiao Xu,Da-Hai Ren
Densities ( ρ ) and viscosities ( η ) for binary mixtures of tri- n -octylamine (TOA) + n -heptane, TOA + n -octane, TOA + n -nonane, and TOA + n -decane are determined at T (283.15, 293.15, and 303.15) K and atmospheric pressure. The excess molar volume is calculated from the density data and is correlated by a Redlich–Kister type equation. The excess molar volume is negative for all the four systems. The results show that the volume accommodation effect is predominant in these systems. The Grunberg & Nissan equation and Fang & He equation for binary mixtures are used to correlate the experimental viscosity data. The Fang & He equation gives an average absolute deviation ( AAD %) of 0.8% for TOA with alkane mixtures, better than that of 3.8% given by the Grunberg & Nissan equation.
研究领域:
物理化学
·
热力学
✓ 已验证
DOI
高影响因子
MOLECULAR PHARMACEUTICS
·
2016
·
IF 4.342
Meirong Huo,Yao Liu,Lei Wang,Tingjie Yin,Chen Qin,Yanyu Xiao,Lifang Yin,Jiyong Liu,Jianping Zhou
A redox-sensitive micellar system constructed from an O,N-hydroxyethyl chitosan–octylamine (HECS-ss-OA) conjugate with disulfide linkages between the hydrophobic alkyl chains and hydrophilic chitosan backbone was synthesized for triggered intracellular delivery of hydrophobic paclitaxel (PTX). In aqueous environments, conjugates formed micelles with high PTX loading (>30%). Mechanistically, the sensitivity of HECS-ss-OA micelles to reducing environments was investigated using the parameters of in vitro release and particle size. Intracellular release of nile red fluorescence alongside cytotoxicity studies further confirmed the potency of redox-sensitive micelles for intracellular drug delivery compared with redox-insensitive micelles. Additionally, an in vivo study confirmed the efficacy of PTX-loaded micelles in tumor-bearing mice with superior antitumor efficacy and diminished systemic toxicity when compared with the redox-insensitive micelles and a PTX solution. These results demonstrate the potential of redox-sensitive HECS-ss-OA micelles for intracellular trafficking of lipophilic anticancer drugs.
研究领域:
药剂学
·
肿瘤学
·
生物材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Yan-Chan Wei,Ding Zhu,Jing Zhang,Hao-Ran Wang,Meng-Zhen Zhou,Shuangquan Liao
The formation of three dimensional network structure is critical in determining mechanical properties of natural rubber (NR). Consequently, it is vital to regulate crosslinking network of NR by controlling vulcanization process. Inspired by our previous studies on contribution of non-rubber components (NRCs) to the excellent properties of NR, we find octylamine in NRCs decreases the activation energy ( E a ) of vulcanization from 82.73 kJ/mol to 44.34 kJ/mol, thereby reducing vulcanization time from 18.67 min to 2.71 min. From microscopic perspective, octylamine tends to coordinate with zinc ions to improve dispersion of ZnO in NR. And octylamine promotes ring-opening reaction of S 8 to favor formation of polysulfide intermediates. Therefore, the incorporation of octylamine remarkably improves vulcanization efficiency, which contributes to the formation of a more homogeneous network with higher crosslinking density, enhancing remarkably the strength and toughness of NR. As a result, the tensile strength and fracture energy of samples are as high as 31.15 MPa and 68.88 kJ/m 2 , respectively. In addition, even with a 60 % reduction in ZnO content, the NR samples still maintain high vulcanization efficiency and excellent mechanical properties after the addition of octylamine, which provides a green and feasible way to alleviate the environmental pollution caused by ZnO.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2016
·
IF 2.101
Qingfa Wang,Qifeng Li,Ruoping Yanzhang,Junfeng Zhang,Xiangwen Zhang
A facile and effective solvothermal method was developed to tailor the morphology and size of Pt nanocrystals by tuning the concentration of 1-octylamine (OAm). Three shaped Pt nanocrystals (NCs), 0D sphere & icosahedra, 2D plate and 3D multipods, were synthesized sequentially with increasing the OAm concentration from 5% to 100% in the solvent mixture OAm and N, N -dimethylformamide (DMF). These Pt NCs exhibited high catalytic performance toward the reduction of p -nitrophenol. The strategy presented in this work open a new avenue for easily developing high dimensional Pt nanocrystals, especially for rare 2D plate.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Mei Liu,Shijing Xu,Shaohua Zhu,Jiazhong Wu,Bofeng Bai,Chengzhen Sun
Following the first part of this study, herein, we focus on the oil-wet rock surfaces formed by the adsorption of polar molecules via base interactions. The effects of ions on the oil–water wettability of quartz surfaces and the mechanism behind the phenomenon are revealed through contact angle measurements and surface characterization. The results indicate that the ions can greatly alter the wettability of the surface to become more water-wet only when the salt solutions are alkaline, with a maximum decrease of approximately 20° in the water contact angle. NaCl and KCl solutions are more effective than CaCl 2 and Na 2 SO 4 solutions. In alkaline solutions, the hydroxyl ions can deprotonate the octadecylamine molecules to weaken their interactions with the surfaces, such that the cations can displace the adsorbed octadecylamine and lead to large desorption from the surfaces. Finally, a quantitative model is established to describe the ion-induced wettability alteration.
研究领域:
地质学
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表面化学
✓ 已验证
DOI
高影响因子
Energy Science & Engineering
·
2018
·Vol. 6
·期 5
·437-447
·
IF 3.553
Chunhua Dong,Xingfu Song,Jie Zhang,Evert Jan Meijer,Hang Chen,Jianguo Yu
A thermal dissociation process (ideally, 100% atom utilization) to regenerate the amine extractant and to produce gaseous HCl which is the key to realizing the CO 2 mineralization with metal chloride waste liquids was investigated. Solvent effects on the thermal dissociation of tri-n-octylamine hydrochloride (TOAHCl) were predicted to be prominent via analyzing structure parameters, charge distribution, solvation free energy, apparent basicity, and N-H frequency with the help of molecular simulation and experiments. Inert solvents with low polarity such as decalin, dodecane were favorable in thermal dissociation experiments. In particular, decalin enhanced the dissociation most effectively which is in agreement with the prediction. In dilute solutions, the thermal dissociation kinetics was shown to be first order. The apparent reaction rate (3.0 × 10 −4 −1.5 × 10 −2 min −1 ) and activation energy (58.219-121.827 kJ/mol) differ a lot at 180-190°C in various solvents, confirming a strong solvent effect. A two-stage reaction scheme in dilute solutions has been proposed from the experimental study. The overall process is entropically driven, with the removal of HCl into gas phase from the solvated state. The work could offer a fundamental direction for the further actual process.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2024
·
IF 4.5
Huihui Xie,Han Xia,Zihan Qin,Zaichao Dong,Xin Wang,Liang Sun,Yang Liu,Yang Zhang
Polymer inclusion membranes (PIMs) exhibit great potential in the separation and recovery of valuable materials from wastewater and secondary resources. In this work the effect of alkyl chain configuration of the functional carriers on the physicochemical properties and permeability of PIMs was investigated. Three tertiary amine isomers with different alkyl chain configurations were selected as carriers: trioctylamine, triisooctylamine, and tris(2-ethylhexyl)amine. Operating conditions like carrier contents, feed solution pH, phenol concentration, and stripping solution properties were also investigated. The results obtained in this study indicate that tertiary amines with less branched alkyl chains perform better phenol transport efficiency. Furthermore, the transport efficiency decreased rapidly with increasing steric hindrance of the carriers. Trioctylamine-based PIM displayed optimal extraction efficiency of 92.8 % and stripping efficiency of 90.8 % due to its lower steric hindrance, higher hydrophilicity, and larger crystallinity. Phenol extraction and stripping efficiencies remained above 85.7 % and 80.8 % after 8 cycles, demonstrating excellent stability.
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
THEORETICAL FOUNDATIONS OF CHEMICAL ENGINEERING
·
2023
·Vol. 57
·期 3
·391-402
·
IF 0.8
Zheng Dan
Abstract This work presents a novel approach for the growth of potassium sulfate (K 2 SO 4 ) from supersaturated solutions by reaction-extractive crystallization in a fluidized-bed crystallizer (FBC), in which K 2 SO 4 is transformed into potassium chloride and sulfuric acid based on a reactive extraction-crystallization process using triisooctylamine (TOA) in n -octanol as the extraction system. This paper uses the moment transformation method to solve the population balance equations of K 2 SO 4 in the extractive crystallization process, and the crystallization kinetic parameters are obtained by nonlinear regression. The kinetic equations of crystal nucleation, growth, and agglomeration rate in the crystallization process of potassium sulfate are determined, and experiments verify the reliability of the kinetic parameters. The results show that in a specific range, higher supersaturation and fluidization rate are conducive to the nucleation, growth, and aggregation of K 2 SO 4 . Suspension density promotes crystal nucleation and growth but has the opposite effect on accumulation. At the same time, based on the constant calculation equation of particle number and the constant calculation equation of mass, the extraction crystallization coupling mathematical model of the crystal in the fluidization state is established. The effects of suspension density, Reynolds number, extraction rate, feeding rate, and extraction concentration on potassium sulfate’s nucleation, growth, and aggregation rate were studied by combining model calculation with experimental research. A process coupling model of the potassium sulfate extraction crystallization process in a fluidized bed was proposed. The model agrees with the experimental results, which have specific guiding significance for industrial production.
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
JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
·
2020
·
IF 2.245
Menglei Zhang,Hao Song,Chenghang Zheng,Zhenglong Lin,Yi Liu,Weihong Wu,Xiang Gao
Disposal of spent catalyst in an economical and green way has become a great concern for industrial production. We developed a process including acid leaching, solvent extraction and stripping in order to recycle spent catalyst. In this study, we conducted selective recovery of molybdenum through focus on finding an optimized extraction and stripping process by comparing different extractants and stripping agents. To separate molybdenum from other metals efficiently and figure out the mechanism of extraction process, the five different extractants of methyl trioctyl ammonium chloride, tri-n-octylamine, tris (2-ethylhexyl) amine, bis (2-ethylhexyl) phosphate, and tributyl phosphate with different functional groups were examined; the extraction ability and extraction mechanism of these five extractants were systematically studied under the same system for the first time. It was found that more than 98% of the molybdenum could be extracted with an organic phase consisting of tri-n-octylamine or methyl trioctyl ammonium chloride under the optimal conditions. The result indicated that the tri-n-octylamine and methyl trioctyl ammonium chloride possess excellent molybdenum extraction ability, the extraction capacity of the rest extractants was in the order of bis (2-ethylhexyl) phosphate > tris (2-ethylhexyl) amine > tributyl phosphate. In the stripping process, NH4OH, NaOH, and H2SO4 were chosen as stripping agent to strip the molybdenum from the loaded tri-n-octylamine organic phase. The stripping ability of the three studied stripping agents was in the order NaOH > NH4OH > H2SO4. The Fourier transform infrared (FTIR) spectra showed that the structure of the tri-n-octylamine organic phase was stable during the extraction and stripping process. Results showed that molybdenum could be highly and efficiently recovered by optimized extraction and stripping process.Implications: A series of different extractants and stripping agent have been systematically studied in order to compare their extraction and stripping ability under the same system. Based on the obtained results, an optimized extraction and stripping process was proposed to recycle molybdenum from spent catalyst efficiently. It is possible to dispose spent catalysts in an economic and environmental way by this developed metal recovery process.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Pan-Pan Zhao,Cong Deng,Ze-Yong Zhao,Xing-Yu Li,Hong Chen,Yu-Zhong Wang
More than 40% of the energy generated globally is consumed by residential and commercial buildings, so energy efficient materials for buildings are urgently needed at present. On-demand thermal energy storage/release using phase change materials (PCMs) can improve thermal energy utilization efficiency, however, they are facing low adaptability to temperature and easy flammability in the case of fulfilling high thermal management capacity. Herein, we report octadecylamine-based PCMs with tailor-made molecular firefighting and thermal energy management capability. These synthesized octadecylamine-based Schiff base-containing PCMs (SB-PCMs) may self-extinguish while encountering short-time fire and possess variable phase transition temperatures of 33, 42, 92, and 101 °C. Meanwhile, these SB-PCMs own high phase transition enthalpies of 161.4–183.4 J g −1 and excellent cyclic stability. When SB-PCMs as thermal energy management materials in wood plastic-based building materials, they show high adaptability to ambient temperature and excellent thermal management capability, achieving temperature regulation of 9.0 °C. Meanwhile, fire safety of the composite wood plastic materials is significantly improved. Detailed analysis confirms that the incorporated benzaldehyde with various positional substituted hydroxyl may induce noncovalent interactions (mainly hydrogen bond and π-π stacking) of SB-PCMs and further control their self-assembling processes, thus achieving multiple thermal responses of SB-PCMs; self-crosslinking charring of benzaldehyde-based Schiff base structure may retard fire spreading, therefore presenting molecular firefighting. Additional multistage thermochromic behaviors of SB-PCMs may extend their application in temperature-sensitive paint, intelligent fabric, etc. This work firstly represents a method for manipulating the multistage thermal and fire responses of PCM in the case of fulfilling high thermal energy management capacity and confirms its molecular-firefighting and energy efficient application in building materials.
研究领域:
材料科学
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能源工程
·
消防安全
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Zhuojun Jiang,Yufeng Liang,Shuyao Xiong,Guo Li,Qian Zhang,Benzheng Xia,Liangrong Yang,Zheng Li
A synergistic solvent extraction system comprising trioctylamine (TOA) and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid (H 3 BO 3 ) and separate boron isotopes. However, the structure of ligands might impact H 3 BO 3 extraction, boron isotope separation, and solvent loss, which has not been thoroughly investigated. This study initially evaluated the influence of ligand’s type, p K a , and substituents on H 3 BO 3 extraction efficiency, as well as the impact of the B (4) -O structure (boron is bound to four oxygen atoms) in the organic phase on isotope separation efficiency. Subsequently, by synthesizing the highly hydrophobic 2-hydroxydodecanoic acid (HYA), the extraction performance and mechanism of the TOA/HYA system were investigated. The findings highlight the superior extraction efficiency when employing di-phenolic hydroxyl, phenolic hydroxyl + carbinol hydroxyl, and alcoholic hydroxyl + carboxyl ligands compared to phenolic hydroxyl + carboxyl, phenolic hydroxyl + ethanol hydroxyl, diol hydroxyl, and dicarboxylic ligands. The organic phase anion complex, exclusively comprising the B (4) -O structure, enhances isotope separation effectiveness. The TOA/HYA system achieves an 80% single-stage extraction efficiency for H 3 BO 3 . H 3 BO 3 and HYA are extracted into the organic phase at a ratio of 1:2, with the anion complex solely containing the B (4) -O structure. This study paves the way for the construction of novel boric acid extraction and boron isotope separation systems.
研究领域:
化学工程
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核化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）