Green Processing and Synthesis
·
2022
·Vol. 11
·期 1
·184-194
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IF 3.97
Qiuyun Zhang,Binbin Yang,Yuanyuan Tian,Xianju Yang,Rongfei Yu,Jialu Wang,Taoli Deng,Yutao Zhang
In the present study, a facile solvothermal method was used for the synthesis of silicotungstic acid (HSiW) immobilized on Ce-based metal organic framework (Ce-BDC) and embedded in Zr-based metal-organic framework (UiO-66(Zr)) composite catalyst, namely, Ce-BDC@HSiW@UiO-66 for the production of biodiesel through green fatty acid esterification. The obtained hybrids were characterized by various characterization technologies, including Fourier transform infrared, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N 2 physisorption, X-ray photoelectron spectroscopy, and temperature-programmed desorption of NH 3 (NH 3 -TPD) analysis. The characterization analyses showed that the hybrids have been successfully synthesized. Also, the volume and pore size of UiO-66(Zr) were changed by introducing HSiW@Ce-BDC, and the resulting Ce-BDC@HSiW@UiO-66 possessed the mesoporous structure and relatively high surface area. Simultaneously, the NH 3 -TPD analysis of Ce-BDC@HSiW@UiO-66 reveals that the acid strength was increased in comparison with HSiW@Ce-BDC. In addition, the composite Ce-BDC@HSiW@UiO-66 demonstrated high catalytic activity, and the oleic acid esterification gave 81.5% conversion at optimum conditions of 0.2 g catalysts, 1:30 oleic acid to methanol molar ratio at 130°C for 4 h. More interestingly, after six recycling cycles, the reduction in the conversion rate was only 4.6%, indicating that Ce-BDC@HSiW@UiO-66 has excellent reusability. Our study provides an effective approach to synthesize multifunctional hybrids for green biofuel production.
研究领域:
化学工程
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催化材料
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可再生资源
✓ 已验证
DOI
高影响因子
RARE METALS
·
2024
·
IF 9.6
Hu Xiao-Jie,Sun Yu-Han,Liu Ling-Yue,Mao Dan-Jun,Zheng Shou-Rong
Monochloroacetic acid (MCAA) is identified as a highly carcinogenic disinfection by-product in chlorinated drinking water. In this study, a series of CeO 2 -supported Pd catalysts (Pd/MCeO 2 ) were synthesized through one-step calcination of Pd-loaded Ce-UiO-66-BDC (Ce-MOF), and the liquid-phase catalytic hydrodechlorination of MCAA was explored using these catalysts. For comparison, Pd/CeO 2 catalysts were additionally synthesized using the conventional impregnation method. The characterization results reveal that the catalysts exhibit strong metal–support interaction, leading to high Pd dispersion and Pd n + content. Additionally, the calcination temperature significantly influences catalytic performance, with the catalyst calcined at 500 °C (Pd/MCeO 2 -500) demonstrating the highest catalytic activity and achieving complete dechlorination of MCAA within 50 min. Furthermore, it is found that the catalytic MCAA hydrodechlorination using the catalysts adheres to the Langmuir–Hinshelwood model. Accordingly, low reaction pH is favorable for the catalytic hydrodechlorination of MCAA, enhancing MCAA adsorption on the catalyst surface due to the electrostatic interaction between MCAA and the catalyst surface. Theoretical results suggest that the presence of Pd n + efficiently facilitates MCAA adsorption and C–Cl cleavage, thus significantly enhancing the liquid-phase catalytic hydrodechlorination. Graphical abstract
研究领域:
环境科学
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催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2024
·
IF 2.6
Yang Zhou,Dan Wang,Qiuxiang Feng,Qi Wu,Feng Cao,Li Jiang,Qianli Zhang,Jie Liu
Synthesizing stable MOF materials with good adsorption capability in a relatively green way is well worth investigating. In this work, a stable Ce-UiO-66-NH2 MOF was constructed from Ce(IV) salts and a bifunctional ligand, 2-amino terephthalic acid, in a mixture of water and ethanol at room temperature. The MOF solid was fully characterized and its adsorption properties for methylene blue were investigated in detail. Ce-UiO-66-NH2 showed excellent removal ability of MB over a wide pH range, the adsorption process followed a pseudo-second-order kinetic model, and the isothermal adsorption data fit well with a Langmuir model with a maximum capacity of 427 mg g−1. Moreover, a spontaneous heat adsorption process was concluded from thermodynamic study, and this MOF sorbent can be reused for several cycles with its structural stability maintained. A possible mechanism for MB adsorption was also proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2022
·Vol. 147
·期 23
·5355-5362
·
IF 5.227
Yi Xia,Jiaxin Zhou,Yanying Liu,Yutong Liu,Ke Huang,Huimin Yu,Xue Jiang,Xiaoli Xiong
Due to their high catalytic activity, stability and low cost, nanozymes with oxidase-like activity have attracted widespread interest in the fields of analytical detection and colorimetric sensing. To further promote the catalytic activity and the sensitivity of dopamine (DA) sensing, herein, a mixed valence Ce-MOF (MVCM) with enhanced oxidase-like activity was synthesized by the dielectric barrier discharge (DBD) microplasma method. Compared with hydrothermal synthesis, the prepared MVCM synthesized using a microplasma showed a higher catalytic activity, which benefits from a low Ce3+/Ce4+ ratio. Due to the spontaneous redox properties of Ce3+/Ce4+ in a MVCM, the MVCM-based colorimetric sensing of dopamine was established and showed a limit of detection of 0.74 μM over a linear range of 5–100 μM with high selectivity and stability and has been applied for the detection of dopamine in sweat. The proposed study provides an effective synthesis method for nanozymes with enhanced activity and shows great promise in widespread analytical and sensing applications.
研究领域:
材料科学
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分析化学
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生物传感
✓ 已验证
产品关联
DOI
PubMed
高影响因子