Green Energy & Environment
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2019
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IF 0
Ge Li,Baodong Wang,Qi Sun,Wayne Qiang Xu,Ziran Ma,Hongyan Wang,Daojun Zhang,Jiali Zhou
A combined acid–alkali hydrothermal method was used to prepare fly ash –derived SAPO-34 molecular sieves from a thermal power plant in Inner Mongolia (China). The specific surface area of the prepared fly-ash-derived SAPO-34 molecular sieves was 579 m 2 g −1 , the total pore volume was about 0.27 cm 3 g −1 , and the pore size was 0.56 nm; the molar ratios of Al 2 O 3 :P 2 O 5 :SiO 2 were 1:0.86:0.45. Cu/SAPO-34 catalysts were prepared by impregnation of low-cost fly-ash-derived SAPO-34 molecular sieves as a support and tested in selective catalytic reduction with NH 3 (NH 3 -SCR). Powder X-ray diffraction (XRD), N 2 adsorption–desorption, X-ray photoelectron spectroscopy (XPS), H 2 temperature-programmed reduction (H 2 -TPR), NH 3 temperature-programmed desorption (NH 3 -TPD), electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), X-ray fluorescence analysis (XRF) and scanning electron microscopy (SEM) were used for catalyst characterization and investigation of the relationships between the catalyst structure and the catalytic activity. The actual silica:alumina ratio of the molecular sieves did not increase with increasing Cu loading, indicating that increasing the Cu loading does not change the original structure of the SAPO-34 molecular sieves. The XRF and NMR results showed that replacement by Cu results in more Si islands. The molecular sieve acidity decreased because of the increased number of Si islands. The NH 3 -TPD results showed that for the Cu/SAPO-34 catalysts there was a low correlation between the low-temperature activity and the amount of acidic sites. SCR activity is closely related to the location of Cu. The 4.47Cu/SAPO-34 catalyst has the highest isolated Cu 2+ showed the highest NH 3 -SCR activities (> 90%) at 250–350 °C. This work opens up new avenues for recycling fly ash formed in coal-fired power plants (reducing environmental pollution) and developing low-cost SCR catalysts for NO x pollution control.
研究领域:
环境科学
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材料科学
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产品关联
DOI
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Mu Liu,Liren Zheng,Xiaolei Bao,Zeyan Wang,Peng Wang,Yuanyuan Liu,Hefeng Cheng,Ying Dai,Baibiao Huang,Zhaoke Zheng
Atomic layer deposition (ALD) technique has been proved to be an efficient method to synthesize or modify catalyst. In this study, Cu was loaded on different TiO 2 substrates, pristine TiO 2 and black TiO 2 (denoted as H-TiO 2 ) to achieve better CO 2 photocatalytic reduction performance. Both TiO 2 @Cu and H-TiO 2 @Cu exhibited dramatic enhancement for CO and CH 4 production. The peculiar phenomenon of TiO 2 outperforming H-TiO 2 after ALD loading was further studied by a series of characterization methods. Even though H-TiO 2 showed superior performance for photocatalytic CO 2 reduction than TiO 2 , pristine TiO 2 loaded with more Cu 0/+ after ALD deposition surpassed the performance of H-TiO 2 @Cu which possessed less amount of Cu 0/+ and more Cu 2+ . Cu 0/+ is proved to be the crucial factor for CO 2 reduction and it is capable of overshadowing the influence of Ti 3+ and V o . These results indicate that not only will ALD technique significantly enhance the CO 2 reduction performance after Cu deposition, but the substrate employed for loading and the chemical state of loaded material will also influence the subsequent catalytic performance. In addition, our result provides additional experiment evidence for justifying the significance of Cu 0/+ in photocatalytic CO 2 reduction reaction.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2024
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IF 8.2
Na Liu,Yinhui Li,Minggu Zhang,Naiju Che,Xianliang Song,Yanli Liu,Chengliang Li
As the substitutes of legacy long-chain per-/polyfluoroalkyl substances (PFASs), short-chain PFASs have been widely detected in the environment. Compared to long-chain PFASs, short-chain PFASs have smaller molecules and are more hydrophilic. Therefore, they are more likely to experience long-distance transport and pose lasting environmental impacts. In this study, Fe-doped (R-Fe) and Cu-doped biochars (R-Cu) were prepared using reed straw biochar (R). The results showed that the PFBA and PFPeA sorption capacities of R-Fe were 25.81 and 43.59 mg g −1 , 1.65 and 1.55 times higher than those of R, respectively. The PFBA and PFPeA sorption capacities of R-Cu were 19.34 and 33.69 mg g −1 , 1.24 and 1.20 times higher than those of R, respectively. In addition, R, R-Fe, and R-Cu exhibited higher PFBA and PFPeA sorption capacities than the biochars previously reported. The excellent PFAS sorption performances of the biochars were attributed to the highly porous structure of R, which provided rich adsorption sites. Ion-pair sorption, pore filling, electrostatic interaction between the Fe/Cu and cationic groups on biochar and the anionic groups of PFASs, and hydrophobic interaction between the hydrophobic surface of biochar and the fluorinated tails of PFASs were the underlying sorption mechanisms. The biochars presented high removal rates (>86 %) of multiple PFASs (∑PFAS: 350 μg L −1 ) from synthetic wastewaters, including legacy and emerging PFASs of different chain lengths and with different functional groups. The biochars reported in this study are promising candidate adsorbents for treating waters contaminated with short-chain PFASs.
CAS / MDL:
研究领域:
环境科学
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污染控制
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Jicheng Wang,Yanhong Quan,Linjie Li,Shunan Yin,Xinxin Ding,Jun Ren
A series of Cu/SBA-15 catalysts with different Cu loadings are prepared by the ammonia evaporation method for the liquid-phase hydrogenation of furfural (FF) to furfuryl alcohol (FA). The results show that the supported Cu loading influences the structure and catalytic activity during FF hydrogenation. The 20Cu/SBA-15 catalyst shows the optimum performance with 99.3 % FF conversion, 99.0 % selectivity to FA, nearly pure FA product, and a turnover frequency reaching up to 81.7h −1 . The effect of Cu loading can be related to Cu dispersion and the interaction between the metal and support, which further promotes the surface Cu + /Cu 0 ratio. Additionally, the correlation of FF conversion with Cu + /Cu 0 ratio confirms that the excellent performance of 20Cu/SBA-15 is mainly derived from the synergy of Cu + and Cu 0 species, although the range of performance is not large. Finally, the optimal reaction conditions are screened using a reaction temperature of 150 °C, a reaction pressure of 4 MPa, a catalyst dosage of 0.1 g, and a reaction time of 60 min. The present study confirms that the Cu loading has a significant effect on the structure of Cu/SBA-15 and nearly pure objective FF product can be feasibly obtained with an appropriate Cu support in the synthesis of FA from FF hydrogenation.
研究领域:
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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Xingling Zhao,Xue Zhou,Yupei Xia,Zihan Xu,Mingjun Song,Zihan Wang,Qingjie Guo,Zaiyong Jiang
Catalytic oxidation of carbon monoxide (CO) by Cu/Al 2 O 3 has garnered increasing interest in recent years due to its promising application prospects. Numerous investigations conducted on the Cu/Al 2 O 3 system, but its catalytic performance for CO oxidation is still not as promising as that of precious metal catalysts. Increasing the loading amount of the active Cu on Al 2 O 3 surface is a feasible method for improving its activity. However, with the increase of Cu loading, the agglomeration and enlargement of Cu particles is inevitable, which reduces the active Cu amount. Therefore, the utilization rate of Cu atoms is not high and the catalytic performance often can not further rise. Enhancing active Cu loading amount as high as possible is a prerequisite to further enlarge the activity of Cu/Al 2 O 3 catalyst. Herein, self-synthesized Al 2 O 3 nanofibers (Al 2 O 3 -nf) with high specific surface area and abundant penta-coordinated aluminum (Al V ) are used as the support to maximize the Cu loading amount by chemical vapor deposition (CVD). And commercially available α-Al 2 O 3 is used for comparative experiment. The high specific surface area could make Cu high dispersion on Al 2 O 3 , even at 20 wt% Cu loads, which is beneficial to high concentration load of active Cu. The catalytic activity of Cu/Al 2 O 3 -nf-CVD gradually increases with the increase of Cu loading from 2 wt% to 20 wt%, exhibiting a clear linear correlation with the surface content of Cu 0 on the catalyst. Meanwhile, this result confirms that Cu 0 plays a crucial role in CO oxidation of Cu/Al 2 O 3 . However, commercial α-Al 2 O 3 reaches its highest activity when the Cu load is 5%, and then its activity begins to decrease due to the agglomeration of particles. Moreover, Cu/Al 2 O 3 -nf-CVD also exhibits remarkable thermal stability for CO oxidation. This work highlights a new strategy to synthesis of high Cu loading amount, high activity and thermostable Cu/Al 2 O 3 catalyst for low-temperature oxidation of CO.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
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2024
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IF 4.4
Bin Guan,Junyan Chen,Zhongqi Zhuang,Lei Zhu,Zeren Ma,Xuehan Hu,Chenyu Zhu,Sikai Zhao,Kaiyou Shu,Hongtao Dang,Zhen Huang
As a significant technology of CO2 utilization, artificial CO2 photoreduction has received more and more attention. Herein, g-C3N4 catalysts modified with Bi and/or Cu for CO2 photothermal reduction were prepared by solvothermal synthesis and impregnation methods. Performance evaluation and physicochemical and photo- and thermochemical characterization indicated that Bi and Cu modification effectively enhanced the photo-absorption properties of g-C3N4 catalysts, improving charge transfer efficiency and catalytic performance. Compared with single-metal modification, Bi and Cu co-modification showed a narrower bandgap and more excellent light and CO2 absorption capacity, suggesting a certain synergistic effect of Bi and Cu co-modification. The alteration of the light absorption properties may be related to the surface plasmon effect of Bi and Cu, and the co-loading of Bi and Cu can exacerbate the effect, which can effectively enhance the photoresponsivity of the catalysts, leading to higher catalytic performance.
研究领域:
催化
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材料科学
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环境科学
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化学工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Zhengfeng Gu,Daiwei Liu,Mengnan Yu,Teng Bao,Xiaowei Liu,Ling Zhang,Haitao Ding,Zhimin Yu,Chengxun Deng
The synthesis of supported transition metal oxides with satisfactory low-temperature catalytic performance and application potential is still a challenge for the complete degradation of VOCs. Ni-Cu-loaded TiO 2 catalysts were prepared by an impregnation method. The lattice defect and oxygen vacancy concentrations of the prepared materials could be tuned by controlling the Ni/Cu molar ratio and the mass proportion of the TiO 2 support. 5Ni-Cu/TiO 2 exhibited the best catalytic activity and showed superior catalytic stability during complete toluene oxidation . The obtained catalysts were fully characterized by XRD, FT-IR, TEM, N 2 adsorption analysis, XPS, H 2 -TPR, O 2 -TPD, TPD analysis, and XPS. The 5Ni-Cu/TiO 2 catalyst had improved pore sizes and specific surface area, had more oxygen vacancies on its surface, had increased concentrations of adsorbed and lattice oxygen species, and had good redox properties; these characteristics were favorable for low-temperature catalytic performance and catalytic stability. Cyclic transformations of metal valence states between Cu + and Cu and between Ni and Ni 2+ were observed in the catalytic system. A potential catalytic reaction process based on the M-vK mechanism was proposed. This work serves as a reference for the application of supported transition metal catalysts for the degradation of VOCs.
研究领域:
催化
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Menglin Li,Xinpeng Wang,Jian Zhang,Yonghao Gao,Wen Zhang
The capture of toxic radioiodine is an increasingly important priority for the safe development of nuclear energy. Copper is a promising alternative for expensive silver to capture iodine. To develop novel copper-based adsorbents and determine the effect of copper species on iodine adsorption, the metal–organic framework with dual-pyrazole ligands (MOF-303) is employed as the scaffold to bind Cu 2+ species. Cu 0 nanoparticles were formed after the reduction by NaBH 4 . The obtained Cu 2+ -MOF-303 and Cu 0 -MOF-303 show high iodine uptake capacities at 353 K, 747 mg·g −1 and 837 mg·g −1 , respectively. They also show high iodine uptake capacities of more than 300 mg·g −1 at a high temperature (423 K), which are better than other Cu-based adsorbents. Besides, the loading of Cu can enhance the iodine selectivity under humid vapor, and iodine adsorption rate in iodine-cyclohexane solutions. The Cu 0 on Cu 0 -MOF-303 can react with iodine directly via the redox mechanism. For Cu 2+ -MOF-303, the adjacent pyrazole ligands can chelate with Cu 2+ ions strongly and transfer charges to trapped iodine to form polyiodide anions, and thus stable CuI species could also be generated. The strategy of anchoring Cu species using MOF-303 provides large channels for iodine diffusion, and highly-dispersed Cu and N sites for iodine capture.
研究领域:
核能
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材料科学
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环境科学
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化学工程
✓ 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）