ACS Catalysis
·
2023
·
IF 12.9
Shaoxia Guo,Zhuoshi Li,Rui Yin,Jianbao Li,Zhuang Zeng,Zhiwei Hu,Guangyuan Luo,Jing Lv,Shouying Huang,Yue Wang,Xinbin Ma
Higher alcohol synthesis (HAS) from syngas is highly attractive but still challenging due to the complexity of the reaction system and the difficulty in modulating the carbon number distribution of products, especially in improving the selectivity toward ethanol or short-chain alcohols over a single catalyst. Herein, we propose a CoMnOx nanocomposite catalyst with the Co/Mn molar ratio of 1/2 prepared by the facile sol–gel method and found that it could selectively produce short-chain alcohols in the HAS. The C2-5OH proportion in the total alcohol reached 75.5 C%, in which the ethanol proportion was as high as 48.0 C%, breaking through the Anderson-Schulz–Flory distribution and outperforming most of the reported cobalt-based catalysts for HAS. Multiple characterizations and contrast experiments indicated that oxygen vacancies in MnOx that formed during reduction and reaction can dissociate CO but are inactive in C–C coupling, thus generating lots of CHx* monomers. The CHx* intermediates could react with the CO* species adsorbed on the neighboring Co2C species, greatly stimulating the production of ethanol. It is also demonstrated that the oxygen vacancies possibly facilitated the carbonization of cobalt and enhanced the alcohol selectivity, while the untransformed CoxMn1–xO was not active in the reaction. These findings may provide potentials in designing catalysts for highly selective production of ethanol and short-chain products in HAS from syngas.
研究领域:
催化化学
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材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Yinhui Li,Haining Wang,Qiuxia Wu,Xin Xu,Shanfu Lu,Yan Xiang
Phosphotungstic acid (H 3 PW 12 O 40 , HPW) molecules were anchored onto carbon nanotubes (CNTs) by electrostatic self-assembly using poly(diallyldimethylammonium chloride) (PDDA); subsequent incorporation of these particles into poly(vinyl alcohol) (PVA) afforded a methanol-blocking membrane for direct methanol fuel cell (DMFC) application. The prepared membrane exhibited a significantly higher proton conductivity of 9.4 mS cm −1 at 60 °C and satisfactory proton conductivity stability over a 120-h test than a PVA membrane. Moreover, the composite membrane showed a decrease in the methanol permeability by ∼40% compared to a PVA membrane (6.10 × 10 −7 cm 2 s −1 ) and much better proton-to-methanol selectivity because of a higher dimensional stability after the incorporation of CNTs. A single DMFC based on the prepared membrane exhibited a maximum power density of 16 mW cm −2 at 60 °C. Thus, CNT-PDDA-HPW/PVA membranes have a great potential as an alternative proton exchange membrane for DMFC application.
研究领域:
材料科学
·
能源科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2022
·
IF 3.662
Chao Zheng,Xiaoyan Yu,Xiaoyi Chen,Mingming Chang
Poly(ethylene oxide)- b -poly(propylene oxide)- b -poly(ethylene oxide) (PEO-PPO-PEO) and acrylamide are both commercially available and widely used water-soluble substances. There are many situations that PEO-PPO-PEO coexist with acrylamide in industry applications, while little is known about the influence of acrylamide on cloud point of PEO-PPO-PEO aqueous solution. In this work, it reveals a universal solubilization of PEO-PPO-PEO by acrylamide. There is always an increase in cloud point with addition of acrylamide no matter what the molecular structure and concentration of PEO-PPO-PEO is. It is found the solubilization is more pronounced when PEO-PPO-PEO is with lower molecular weight or lower weight fraction of PPO segments. On the other hand, the cloud point of systems at lower concentration is more sensitive to addition of acrylamide. On the contrary, polyacrylamide exhibits an opposite impact on cloud point of PEO-PPO-PEO. Acrylamide/PEO-PPO-PEO solution changes from clear to cloudy after polymerization of acrylamide.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Separation Science Plus
·
2024
·
IF 1.3
Boyu Chen,Shengkai Liu,Hongxin Zhi,Jin Huang,Han Song,Jiashen Fan,Yujie Fu,Zhiguo Liu
Green extraction of the active lignans from Schisandra chinensis has received considerable attention due to their promising applications in the biomedical field. In this study, microwave-assisted deep eutectic solvent method was used to simultaneously extract five lignans: Schizandrol A, Schizandrol B, Schisantherin A, Schisandrin A and Schizandrin B. The extraction parameters were optimized according to the calculated comprehensive score obtained from the analytic hierarchy process combined with the entropy weight method. The optimal extraction conditions were that the molar ratio of choline chloride and glycolic acid is 4:1, water content is 30% (V/V), solid–liquid ratio is 1:20 (W g :V mL ), extraction time is 20 min, and extraction temperature is 70°C, under which the extraction rate of the five lignans were 10.89, 8.616, 4.019, 4.893, and 5.318 mg/g. These results confirmed that our extraction method is efficient and feasible for green extraction of lignans from S. chinensis .
研究领域:
药学
·
分析化学
·
绿色化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Rui Hong,Ri-Tong Lan,Yue Ren,Lu Xu,Yun-Xiang Xu,Nouman Ali Shah,Rizwan M. Gul,Shishu Huang,Lingli Li,Jia-Zhuang Xu,Zhong-Ming Li,Ka Li
Oxidation resistance is strongly necessary for the use of crosslinked ultrahigh molecular weight polyethylene (UHMWPE) in artificial joints. The hybrid antioxidant strategy emerged as a promising alternative to the single rival that relies on vitamin E (VE). The goal of this study was to investigate the universality of the antioxidant synergy between VE and sugar alcohol (SA). Three types of SA, including D-sorbitol, maltitol and erythritol, were employed to cooperate with VE. Compared to the use of VE alone, these hybrid antioxidants generally enabled the corresponding UHMWPE composites with prolonged oxidation induction time (OIT) and increased crosslink density. The correlation between OIT and crosslink density of VE/SA-stabilized UHMWPE composites showed low attenuation. The applicability of the hybrid antioxidants to protect UHMWPE against oxidation was further demonstrated using the in vitro clinically relevant accelerated aging. Among the used SA, D-sorbitol exhibited the strongest ability to enhance the synergetic efficiency. The possible mechanism was revealed from the following aspects: the number of secondary hydroxyls per molecular mass and the molecular polarity determined via polarity parameter calculation. These findings provide significant insights for fabricating UHMWPE bearing materials with superior comprehensive performance and extended service longevity.
研究领域:
材料科学
·
生物医学工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Greenhouse Gas Control
·
2019
·
IF 3.231
Fan Cao,Hongxia Gao,Qian Xiong,Zhiwu Liang
CO 2 absorption performance for various blended N ,N- dimethylethanolamine (DMEA) solutions in the presence of absorption promoters including Monoethanolamine (MEA), Piperazine (PZ), 2-(Ethylamino)ethanol (EAE), 2-(Methylamino)ethanol (MAE) and 2-Amino-2-methyl-1-propanol (AMP) was investigated in terms of CO 2 absorption flux by using a polytetrafluoroethylene (PTFE) hollow fiber membrane contactor. The experimental results show that the CO 2 absorption flux increases with a reasonable increase in liquid velocity, liquid temperature and total amine concentration. Also, the CO 2 absorption flux can increase by increasing gas velocity, CO 2 partial pressure but decrease with the increased lean CO 2 loading. In addition, it can be found that all of the investigated activated amines can improve the CO 2 absorption flux of aqueous DMEA solution. For fresh amine solution, the order of CO 2 absorption flux for the investigated amine blends can be ranked as: DMEA < DMEA + AMP < DMEA + MEA < DMEA + EAE < DMEA + MAE < DMEA + PZ. By contrast, for the amine solution with CO 2 loading of over 0.3 mol/mol, the order has also changed accordingly and can be ranked as: DMEA < DMEA + AMP < DMEA + EAE < DMEA + MAE < DMEA + MEA < DMEA + PZ. The DMEA + PZ mixture presents a significant improvement up to 52.44% in CO 2 absorption flux compared to that of single DMEA solution, and can be considered as a promising alternative for CO 2 capture.
研究领域:
化学工程
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环境科学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Russian Journal of Physical Chemistry A
·
2019
·Vol. 93
·期 4
·696-702
·
IF 0.581
Huanxin Li,Zhang Haihan,Dou Yonghui,Xu Li,Liu Guoji
Abstract The solubility of (1R,2R)-(+)-1,2-diaminocyclohexane L-tartrate (DHT) in methanol + water, ethanol + water, and 2-propanol + water mixed solvents were measured using a synthetic method with alcohols mass fractions varying from 0.1 to 0.5 over 278.15 to 318.15 K under atmospheric pressure ( P = 0.1 MPa). It was proved that the solubility of DHT in the three binary solvents increased with increasing temperature, while decreased with the mass fraction of alcohols rising. The experimental solubility data were correlated by the modified Apelblat equation and Sun model. The modified Apelblat model showed better agreement with the experimental data than the other model. Furthermore, the thermodynamic parameters including \(\Delta G_{{{\text{sol}}}}^{^\circ }\) , \(\Delta H_{{{\text{sol}}}}^{^\circ }\) , and \(\Delta S_{{{\text{sol}}}}^{^\circ }\) for DHT in the dissolution process were obtained from Van’t Hoff plots.
研究领域:
物理化学
·
药物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2020
·Vol. 20
·期 4
·2408-2415
·
IF 1.134
Lou Jufeng,Chen Feng,Wu Xi-Lin,Lin Hongjun,Chen Jianrong
New synthetic method toward carbon supported catalysts with improved performance is of great importance in direct alcohol fuel cells (DAFCs). Herein, onion-like nanocarbons (OLNCs) were fabricated by using cheap and readily available candle as the raw material. And a facile one-pot
and surfactant-free solvothermal approach was developed for the fabrication of PtSn nanoparticles supported on the OLNCs. Transmission electron microscopy (TEM) images showed the highly crystalline PtSn nanoparticles with size of ~2–5 nm were evenly deposited on the surface of the OLNCs.
The obtained PtSn/OLNCs nanocomposites with Pt loading of about 10.1% exhibited excellent electrocatalytic activity toward both methanol oxidation reactions (MOR) and ethylene glycol oxidation reactions (EGOR). The current density of PtSn/OLNCs is 2.6 and 2.7 times of the commercial 20 wt%
Pt/C toward the MOR and EGOR, respectively, suggesting the great application potential of the PtSn/OLNCs catalyst in DAFCs. The highly electrocatalytic activity of the PtSn/OLNCs may arise from the ultra-small size of the PtSn NPs as well as the large surface area and good electric conductivity
of the OLNCs support. This study not only provides an example of the cost-effective fabrication and application of the OLNCs based catalysts and also sheds a new light on the application of the PtSn/OLNCs catalyst in DAFS.
研究领域:
材料科学
·
电化学
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能源科学
✓ 已验证
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Jing Tang,Xiangshuai Meng,Xiujie Cheng,Qingqing Zhu,Dongxia Yan,YuJin Zhang,Xingmei Lu,Chunyan Shi,Xiaomin Liu
The recycling of poly(ethylene terephthalate) (PET) is an important issue for environmental protection and resource conservation. Methanol alcoholysis is the main chemical method commonly used today to degrade PET into high-value monomers. However, conventional methanolysis of poly(ethylene terephthalate) (PET) has problems such as high temperature and high pressure. To further reduce the temperature of methanolysis, in this work, cosolvent-enhanced methanol alcoholysis of PET polyesters was employed and systematically compared with the common methanol alcoholysis process. The results showed that the addition of a cosolvent could significantly lower the reaction temperature and shorten the reaction time compared with conventional methanol alcoholysis. The 100% conversion of PET can be achieved at 120 °C and 2 h. Meanwhile, the mechanisms for choosing acetonitrile as the best cosolvent for the reaction were investigated by combining experimental characterization and DFT simulation calculations and proposed the relevant basis for selecting a cosolvent. The experimental results showed that the addition of the cosolvent could increase the specific surface area of PET, which increased the mass transfer coefficient of methanol and enhanced the mass transfer process of the reaction, thus promoting the contact between methanol and PET and making the reaction easier. In addition, the kinetic study revealed that the addition of the cosolvent acetonitrile reduced the activation energy of the reaction from 106.9 to 90.3 kJ/mol, thus making the reaction easier to proceed. This paper provides a new method for achieving efficient methanolysis of PET.
研究领域:
环境科学
·
化学工程
·
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2023
·Vol. 30
·期 6
·1-8
·
IF 2.8
Yu Dayang,Zhong Jiachun,Pu Zejun,Hou Hongbo,Li Xianyong,Zhu Rongli,Wang Xu,Wu Fang,Zheng Pan,Liu Jingyue
In this study, iso-sorbitol type polycarbonate (PIC) was synthesized with isosorbide (ISB) and diphenyl carbonate (DPC) as reactive monomers. The flexible co-monomers 1,4-butanediol (BDO) and 1,4-cyclohexane dimethanol (CHDM) were introduced to improve its property. Then, two iso-sorbitol type polycarbonate copolymers were obtained: Isosorbitol type polycarbonate copolymer (PIBC) containing 1,4-butanediol (BDO) and isosorbitol type polycarbonate copolymer (PICC) containing 1,4-cyclohexane dimethanol (CHDM). The results of 1 H-NMR and FT-IR demonstrated that the structures of PC, PIC, PIBC, and PICC synthesized by the experiment were consistent with the theoretical structures. The results of the characteristic viscosity test suggested that the copolymer with high relative molecular weight was successfully prepared. The results of DSC and TGA revealed that the introduction of a flexible copolymer increased the relative molecular weight of the copolymer, decreased the glass transition temperature, and exerted little effect on the thermal stability of the copolymer. The mechanical properties test results unveiled that PICC has good mechanical properties. Owing to its excellent mechanical and thermal properties, there is a broad application prospect of the PICC as a green polycarbonate material.
研究领域:
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 9
·期 23
·6749-6759
·
IF 5.726
Wei Chen,Tongyang Song,Jingxia Tian,Peng Wu,Xiaohong Li
Indirect CO2 conversion to ethylene glycol (EG) and methanol (ME) via CO2-derived ethylene carbonate (EC) as the intermediate is an attractive and promising approach. Cu-Based catalysts have been regarded as effective catalysts for the hydrogenation of EC to yield ME and EG. In this work, we prepared Cu/SiO2 catalysts through different methods for the hydrogenation of EC to yield ME and EG. The results show that Cu/SiO2-AE catalysts prepared by an ammonia evaporation (AE) method are superior to Cu/SiO2-DP catalysts prepared by a deposition–precipitation (DP) method. After modification using glucose with an optimal amount, the Cu8G1/SiO2-AE catalysts showed enhanced catalytic performance, furnishing 86% selectivity to ME and 99% selectivity to EG at almost full conversion of EC, with a TOF value for ME formation reaching about 39 h−1. A series of techniques such as N2 sorption, ICP-AES, FT-IR, H2-TPR, H2-TPD, TEM, and XPS were adopted to characterize the physicochemical properties of relevant catalysts. It was found that the Cu/SiO2-AE catalyst had a smaller Cu particle size. After modification with glucose, the Cu8G1/SiO2-AE catalyst had the smallest Cu particle size, the highest hydrogen adsorption ability, and the strongest interaction of Cu with SiO2 so that the highest Cu+/(Cu0 + Cu+) molar ratio was detected. In addition, upon investigation of catalyst stability and reusability, it was found that glucose modification for the Cu/SiO2-AE catalyst can also alleviate the deactivation distinctly.
研究领域:
化学工程
·
催化材料
·
环境科学
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2022
·Vol. 33
·期 10
·3455-3469
·
IF 3.348
Zishuo Ye,Hailin Lu,Endong Jia,Jian Chen,Lifeng Fu
Polyvinyl alcohol (PVA) hydrogels have potential applications in bionic articular cartilage due to their good biocompatibility and low friction. However, the lack of adequate mechanical properties is a key obstacle for PVA hydrogels to replace natural cartilage. In this study, polyethylene glycol (PEG) was introduced into the PVA hydrogel, and the (PVA/PEG) composite gels were prepared by a blending physical cross-linking method. The PVA/PEG gels were treated with a simple and novel organic solvent immersion dehydration to improve its mechanical and tribological properties. And the using of organic solvents for dehydration changed the network structure of the PVA/PEG gels, which improved the mechanical properties effectively. In this study, the effects of different organic solvents on the tribological properties, swelling ratio, shore hardness, and dehydration rate of PVA/PEG hydrogels were investigated. Compared with natural drying, organic solvent dehydration reduced the gel formation time. Notably, the organic solvent dehydration treatment reduces the wear rate of PE ball friction pair to 27.4% of the original amount, improving wear resistance. Meanwhile, self-healing and cellular immune assays demonstrated the excellent biocompatibility and self-healing ability of the PVA/PEG gels. This study provides a new candidate material for the design of articular cartilage, which is expected to advance the progress of artificial cartilage repair.
研究领域:
生物材料学
·
医学工程
·
组织工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）