JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xiuqing Yu,Ruirui Yue,Shiyao Yang,Changqing Fu,Jinbing Shu,Liang Shen
Developing a novel catalyst with lower noble-metal loading and higher catalytic efficiency is significant for promoting the widespread application of direct alcohol fuel cells (DAFCs). In this work, poly(3,4-ethylenedioxythiophene) (PEDOT) supported the PdSn alloy (PdSn/PEDOT) were simply synthesized and their electrocatalytic performance toward the oxidation of ethylene glycol and ethanol (EGOR and EOR) were investigated in alkaline media, respectively. In comparison with other control catalysts, the optimized Pd 4 Sn 6 /PEDOT catalyst exhibits the highest mass activity (7125/4166 mA mg Pd −1 ) and specific activity (26/15 mA cm −2 ) towards EGOR/EOR. The mass activity of Pd 4 Sn 6 /PEDOT for EGOR and EOR are 11.9 and 10.9 times higher than commercial Pd/C, respectively. Moreover, chronoamperometry (CA) and successive cyclic voltammetry (CV) tests show that the CO resistance ability and durability of the Pd 4 Sn 6 /PEDOT catalyst were superior to Pd 4 Sn 6 , Pd/PEDOT and commercial Pd/C catalysts, which can be attributed to the d-band center of Pd can be effectively downshifted and the interface strain effect between electrons caused by the conjugated structure between PEDOT groups. This work provides an effective strategy for the development of highly efficient anode catalysts of DAFCs.
研究领域:
化学
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材料科学
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电化学
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DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 13
·7179-7185
·
IF 2.936
Ruiyun Li,Heyuan Song,Guoqin Wang,Jing Chen
Ketalization of cyclohexanone with glycol has been carried out using molecular sieve SBA-15 immobilized Brønsted acidic ionic liquid catalyst. The properties of the heterogeneous catalysts were characterized by elemental analysis, Fourier transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), thermogravimetry/differential scanning calorimetry (TG/DSC), and N2 adsorption–desorption (BET). The results suggested that Brønsted acidic ionic liquid [BSmim][HSO4] had been successfully immobilized on the surface of SBA-15 and the catalytic performance evaluation demonstrated that the catalyst BAIL@SBA-15 exhibited excellent catalytic activities in the ketalization of cyclohexanone with glycol. In addition, the effects of reaction temperature, catalyst loading, reaction time, and reactant molar ratio have also been investigated in detail, and a general reaction mechanism for the ketalization of cyclohexanone with glycol was given. The SBA-15 immobilized ionic liquid can be recovered easily and after reusing for 5 times in the ketalization reaction, the catalyst could still give satisfactory catalytic activity.
研究领域:
化学工程
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材料科学
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DOI
PubMed
高影响因子
International Journal of Refrigeration
·
2019
·
IF 3.177
Tao Jia,Shengshan Bi,Jiangtao Wu,Panyuan Li
Experimental solubilities of difluoromethane (R32) in polyol ester (POE), polyvinylether (PVE), and polyalkylene glycol (PAG) base oils were measured in the temperatures range from 273 K to 351 K based on the isochoric method. The experimental setup was checked by measuring the solubility of carbon dioxide in n -decane at pressures from 0.1 to 4.6 MPa. The expanded uncertainty ( k = 2) of the measured solubility data was estimated to be less than 2.8%. The experimental solubility data were correlated using the Peng–Robinson (PR) equation of state (EOS) and Wilson activity coefficient model. The absolute average deviations of the experimental data and calculated values for R32 in POE, PVE, and PAG base oils were 1.74%, 0.73%, and 0.97%, respectively. The solubility of R32 in three base oil were calculated and compared at same temperatures and pressures, and the results showed that the solubility order of R32 in the three base oils was: PAG > PVE > POE.
研究领域:
化学工程
·
制冷技术
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DOI
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2023
·Vol. 53
·期 12
·2397-2410
·
IF 2.9
He Xinkuai,Guo Ruqing,Hu Zhousi,Zou Qingtian,Yang Jingjing,Wu Luye
The co-deposition behavior of Co(II) and Mo(VI) and Co–Mo electro-crystallization mechanism in ethylene glycol (EG) are recorded using cyclic voltammetry and chronoamperometry. These results indicate that the Co–Mo co-deposition is representative induced deposition; Co(II) species can facilitate Co–Mo co-deposition, inversely, Mo(VI) species can inhibit Co(II) reduction and the effect can be enhanced as Mo(VI) concentration increases. Additionally, Co–Mo co-deposition in EG takes place through an instantaneous nucleation and diffusion-controlled three-dimensional growth mechanism. Co–Mo deposits with various Mo contents and different microstructures can be obtained from the EG solution. SEM micrographs present that the Co–Mo deposits with 1.56 wt% Mo present a pure pompon microstructure. Benefiting from the composition engineering by alloying with Mo, as well as the simultaneous presence of a suitable pompon structure, Co–Mo deposits with 1.56 wt% exhibits prominent electrocatalytic durability and activity with a η 10 of 84 mV for HER in a 1.0 M KOH. Graphical abstract
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 84
·53346-53354
·
IF 3.108
Zhuang Xu,Wenjing Lou,Xinhu Wu,Xiaobo Wang,Junying Hao
MoS2–polydopamine–methoxypolyethyleneglycol amine (MoS2–PDA–MGA) was synthesized through the combination of mussel-inspired chemistry and the Michael addition reaction. The modification of MoS2 via PDA and MGA enhanced its dispersion stability in oil. The tribological properties of MoS2–PDA–MGA for use as additives in polyalkylene glycol (PAG) base oil were investigated using an oscillating reciprocating tribometer at elevated temperatures. The results indicated that the addition of 0.7 wt% MoS2–PDA–MGA in PAG resulted in excellent friction-reducing and anti-wear (AW) performances compared with PAG base oil. The tribological results of MoS2–PDA–MGA and MoS2 dispersed in PAG base oil after settling for 7 days indicate that MoS2–PDA–MGA, with its good dispersion stability, has stable friction-reducing and AW properties. XPS analysis suggested that a protective boundary film formed on the wear surfaces during the friction and wearing process, which was believed to be responsible for the excellent tribological performance of MoS2–PDA–MGA dispersed in PAG at elevated temperature.
研究领域:
材料科学
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化学工程
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机械工程
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DOI
高影响因子
GREEN CHEMISTRY
·
2017
·Vol. 20
·期 3
·713-723
·
IF 9.125
Yongqiang Zhang,Phongphat Prawang,Chunshan Li,Xiangzhan Meng,Yu Zhao,Hui Wang,Suojiang Zhang
Artemisinin is a kind of natural antimalarial drug exhibiting low toxicity and a very fast action against malaria. Solvent extraction is the most widely used method to separate artemisinin from the Chinese medicinal herb Artemisia annua L. In this study, a series of monoether-based solvents were investigated to extract artemisinin, and propylene glycol methyl ether (PGME) was found to be the most appropriate one for this extraction. Ultrasonic irradiation was demonstrated to be able to assist artemisinin extraction. Influence of extraction conditions, including liquid/solid ratio, extraction temperature, ultrasonic time, and ultrasonic power, on the extraction efficiency were discussed by single-factor experiments, and the main influencing factors were optimized by response surface methods. The extraction mechanism was explored using spectroscopic characterizations, and kinetics of this process was also studied. Results indicated that ultrasonic assisted extraction using PGME had faster extraction rate than conventional solvents, and ultrasonic could significantly enhance mass transfer. Compared with conventional extraction, the process developed here exhibited a higher efficiency (13.79 mg g−1vs. 13.29 mg g−1) and shorter extraction time (decreased from 8 h to 0.5 h) at a relatively low temperature. In addition, PGME had low toxicity and volatility, making the extraction process more safe and reliable. Therefore, this proposed method demonstrated that PGME-based ultrasonic assisted extraction is a rapid, efficient, simple and safe technique for natural product extraction.
研究领域:
药用植物学
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天然产物化学
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中药学
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DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2019
·
IF 3.834
Tongxin Song,Fei Gao,Yangping Zhang,Ping'er Yu,Cheng Wang,Yukihide Shiraishi,Shujin Li,Caiqin Wang,Jun Guo,Yukou Du
At present, it is still a great challenge to control the morphology and size of nanoparticles for obtaining more efficient and stable catalysts for direct fuel cell reactions. Herein, we have synthesized a series of Pd 3 Sn bimetallic catalysts with different morphologies that transitioned from nanonetwork to nanostrips and then to nanodots by altering the varieties of reducing agents and the amount of surfactant. And the formation mechanisms of nanocatalysts were also investigated. It is worth noting that Pd 3 Sn-dots, due to the unique structure, uniform dispersion and ultra-small size, exhibit excellent electrocatalytic activity for ethanol oxidation reaction and ethylene glycol oxidation reaction, which distinctly higher than the other Pd 3 Sn catalysts and commercial Pd/C catalysts. Moreover, the as-prepared Pd 3 Sn catalysts also performed greater long-term durability due to the electronic and synergistic effects. This work provides guidance on the morphology-dependent nanocrystals, which will show a great potential as anodic catalysts in direct fuel cell applications.
研究领域:
材料科学
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电化学
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DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Lejun Feng,Danxing Zheng,Weijia Huang
In this work, three new working pairs, {fluoroethane (HFC161) + dimethylether tetraethylene glycol (DMETEG)}, {HFC161 + dimethylether triethylene glycol (DMETrEG)} and {HFC161 + dimethylether diethylene glycol (DMEDEG)}, are proposed for absorption power cycle. The working pairs are assessed from both thermodynamics and thermokinetic perspective. By combining the microcalorimetry and isothermal synthesis methods, an experimental apparatus was developed to simultaneously obtain the microcalorimetry and vapour–liquid equilibrium data. Then, the solubility and absorption enthalpy data of the three new working pairs were sync-measured at 303.15 K by this sync-measurement experimental apparatus. The thermodynamics data indicated that the affinities of the three working pairs increased from strong to weak in the following order: HFC161 + DMETEG > HFC161 + DMETrEG > HFC161 + DMEDEG. Then the thermokinetic parameters of the absorption rate constant and activation energy were analysed based on the thermokinetic experiment at (303.15, 313.15, 323.15, and 333.15) K. As a result, the affinities of the three working pairs are consistent with the previous thermodynamics study. In addition, the intermolecular interactions within the three systems were analysed according to the intermolecular hydrogen bonds; overall, the (HFC161 + DMETEG) system is considered to be the potential option for applications.
研究领域:
化学工程
·
热力学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Tiefeng Wang,Xu Li,Jinxiang Dong
Ethylene glycol (EG), synthesized from coal-based syngas, is frequently contaminated with refractory impurities 1,2-butanediol (BDO) and 1,2-propanediol (PDO), which affect the quality of EG for polyester production. Distillation, one of the existing methods employed, is still difficult for separation and purification due to the close boiling points. Melt crystallization is an effective technology to obtain high-purity organic compounds based on the difference in the melting points of each component in the mixture. Thus, in this work, we have explored the feasibility of the static melt crystallization on the separation of these two binary systems, EG/BDO and EG/PDO, respectively. For this purpose, a jacketed crystallization tube was adopted and the process was divided into three stages: seed generation, crystallization, and sweating. The crystallization parameters were investigated and fractal porous media theory was used to describe the state of the crude crystals. Furthermore, sweating was applied as a finishing treatment. The purity of ethylene glycol was recorded using gas chromatography, and its corresponding UV transmittance spectrum was studied. The results showed that the purity of ethylene glycol could reach ≥99.8% from the two binary systems studied and its UV transmittance at 220 nm was significantly improved by the tertiary separation process. Overall, melt crystallization has been proved as an effective way to solve the difficulty of separating these short-chain glycols.
研究领域:
化学工程
·
材料科学
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DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2014
·
IF 2.241
Changshen Ye,Xiaolian Dong,Wenjie Zhu,Dongren Cai,Ting Qiu
Isobaric vapor–liquid equilibrium (VLE) data for three binary systems (PM + PMA, MeAc + PM and MeOH + PMA) at 101.3 kPa were measured in a double circulating still of modified Othmer type. The thermodynamic consistency of the experimental data was checked by Herington method. The experimental data were correlated with NRTL and Wilson models. The binary interaction parameters of both models have been obtained by simplex method. The root mean square deviations (RMSD) for the vapor phase fraction and the boiling temperature are less than 0.01 and 0.5 K, respectively. The results indicate that the calculated values by NRTL and Wilson models are in good agreement with the experimental data and no azeotropic behavior has been found in the three binary systems. The research findings would provide basic data for the design and analysis of distillation process.
研究领域:
化学工程
·
热力学
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产品关联
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 23
·4317
·
IF 3.06
Wei Hu,Lei Wang,Quanyong Wang,Anbo Luan,Yuliang Mai,Linjia Huang,Yongjun Chen,Shijing Yan,Wenjie Xiong
The high crystallization at room temperature and high cost of polyoxytetramethylene glycol (PTMG) have become obstacles to its application. To overcome these problems, a segment of PTMG can be incorporated into a block copolymer. In this work, polypropylene (PPO) glycol-polyoxytetramethylene (PPO-PTMG) multiblock copolymers were designed and synthesized through a chain extension between hydroxyl (OH)-terminated PPO and PTMG oligomers. The chain extenders, feed ratios of the catalyst/chain extender/OH groups, reaction temperature, and time were optimized several times to obtain a PPO-PTMG with low crystallization and high molecular weight. Multiblock copolymers with low crystallization and high average molecular weight (Mn= 1.0–1.4 × 104Dalton) were harvested using m-phthaloyl chloride as the chain extender. The OH-terminated PPO-PTMG multiblock copolymer with highMnand a functionality near two was further siliconized by 3-isocyanatopropyltrimethoxysilane to synthesize a novel silyl-terminated polyether. This polyether has an appropriate vulcanizing property and potential applications in sealants/adhesive fields.Keywords:polypropylene glycol-polyoxytetramethylene glycol block multicopolymers;chain extender;m-phthaloyl chloride;adhesives;structure optimizing
研究领域:
材料科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Si-Tong Zheng,Zi-Ying Wang,Zhen Liu,Yingxiang Du,Ling Cao,Sheng Tang,Hian Kee Lee,Yaozuo Yuan,Hai-Wei Shi
Ethylene glycol (EG) and diethylene glycol (DEG) are two contaminants known to cause a variety of human health problems, when ingested in certain amounts, they can cause adverse effects such as nephrotoxicity, neurotoxicity and even death. They are widely found in propylene glycol, which is commonly used as a base for pharmaceutical syrups. The aim of this study was to develop an analytical method for the evaluation of EG and DEG in commercially available pediatric syrups. In this study, a fast, simple and reliable ultrahigh performance supercritical fluid chromatography-electrospray ionization-mass spectrometry (UHPSFC-ESI-MS) method was developed. The work involved the evaluation of three derivatization reagents for UHPSFC-ESI-MS. Benzoyl chloride was finally selected as the optimal derivatization reagent. Compared with an approach without derivatization, the present method achieved the separation and detection of EG and DEG efficiently, sensitively and rapidly, and analysis of EG and DEG in syrup formulations was realized within 7 min. The linear determination coefficients of EG and DEG in the concentration range of 0.25–25.0 μg/mL were greater than 0.999. The limits of detection for EG and DEG were 0.02 μg/mL and 0.07 μg/mL, respectively, and the limits of quantification were 0.09 μg/mL and 0.25 μg/mL, respectively. The recovery rates of DEG and EG ranged from 85.5%–108.1% and 86.7%–117.2%, respectively. The absolute values of the matrix effects in the three types of syrups considered were all less than 10%. Meanwhile, a gas chromatography-hydrogen flame ionization detection method was established for cross-testing of the analytical results. In 10 batches of syrup formulations, DEG was not detected by either method. The presence of EG was detected by UHPSFC-ESI-MS in only three batches, none of which exceeded 90.23 parts per million (ppm), with a mean absolute error of 5.95 ppm between the two sets of results. The developed UHPSFC-ESI-MS method was rapid, simple, efficient, sensitive and accurate for the determination of EG and DEG in genuine syrup formulations.
研究领域:
分析化学
·
药学
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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）