MATERIALS & DESIGN
·
2022
·
IF 9.417
Zongqi Feng,Tingyu Yang,Tiantian Liang,Zhouying Wu,Ting Wu,Jianbin Zhang,Lan Yu
Biomineralization is a common phenomenon in nature, and organisms can prepare functional materials with multi-level ordered structures through biomineralization. Herein, inspired by biomineralization, for the first time, we developed an amino acid quantum dots (ACDs)–CO 2 -Ca(OH) 2 system to study the biomineralization process of CaCO 3 in the presence of ACDs. The ACDs could not only control the morphology and crystal form of CaCO 3 but also could be doped into CaCO 3 during the formation of CaCO 3 to form ACDs@CaCO 3 organic–inorganic hybrid fluorescent materials which had excellent luminous ability. Meanwhile, the morphology and crystal form of CaCO 3 could also be controlled by controlling the CO 2 flow rate and rotation speed. After that, a possible biomineralization mechanism of CaCO 3 in the presence of ACDs was proposed. Finally, the synthetic spherical ACDs@CaCO 3 were applied to the field of biological imaging for the first time. Our work not only provides new bionic methods for the synthesis of multifunctional biomineralized materials and new insights for further understanding of biomineralization mechanism, but also the synthesized new biomineralization fluorescent materials have great application potential in the field of bioimaging.
研究领域:
材料科学
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生物化学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2023
·
IF 4.3
Xi-shuo Wang,Ying-jiao Li,Ting-ting Qi,Ji-wen Fu,Guang-Wen Chu,Bao-chang Sun
In industry, H-type zeolites are usually synthesized under hydrothermal conditions in the sodium-containing system, in which great deal of ammonia nitrogen wastewater will be produced during the transformation of zeolites from Na-type to H-type. In this work, we prepared ZSM-5 zeolites in the sodium-free system using organic amines in a rotating packed bed (RPB), which can greatly reduce the amount of wastewater. It was found that the ZSM-5 zeolites synthesized by isopropanolamine (MIPA) had the highest acid amount with a value of 2.331 mmol/g compared to that by other three amines, and exhibits the highest conversion of benzaldehyde with a value of 77.63% in the acetal reaction of benzaldehyde and ethylene glycol . More importantly, RPB premixing can improve the transfer of Al into the framework of ZSM-5 zeolites relative to conventional stirring technique. This work provided a new route to prepare ZSM-5 zeolites with high acid amount in sodium-free system.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
ENERGY
·
2024
·
IF 9
Deshi Yang,Jianpeng Huang,Zhipeng Hu,Shiqi Qin,Jiaxin Mu,Fengqiang Wang,Zhijun Zhang,Yanjun Xie,Shouxin Liu,Qingwen Wang
Catalytic fast pyrolysis (CFP) of lignin aiming monocyclic aromatic hydrocarbons (MAHs) is attractive. Five metal oxide catalysts (named c-Nb 3 Al x ) with different Nb/Al ratios, c-Nb, c-Al, c-Nb 3 Al 1 , c-Nb 3 Al 2 and c-Nb 3 Al 3 were synthesized and applied to CFP of lignin. Among these catalysts, c-Nb 3 Al 2 exhibits excellent deoxygenation ability and the highest selectivity for MAHs (77.0 %). The selectivity and deoxygenation capacity of c-Nb 3 Al 2 for MAHs were higher than H-ZSM-5 (25) as a control. It was attributed to the large external surface area (90 m 2 g -1 ), mesoporous structure (16.15 nm) and high acid amount (2.00 mmol NH 3 /g cat ) of c-Nb 3 Al 2 . The c-Nb 3 Al 2 has good stability and can be regenerated by simple calcination . The selectivity of the regenerated c-Nb 3 Al 2 for MAHs was still high at 70.1 %. Guaiacol was used to compare the difference in the deoxygenation capacity of c-Nb 3 Al 2 and H-ZSM-5.
研究领域:
化学工程
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材料科学
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催化
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生物能源
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 2
·361
·
IF 3.06
Haili Wang,Wenfeng Han,Xiliang Li,Bing Liu,Haodong Tang,Ying Li
Cr2O3nanoparticles were prepared by solution combustion synthesis (SCS) with chromium nitrate as the precursor and glycine as the fuel. Commercial Cr2O3and Cr2O3prepared by a precipitation method were also included for comparison. The morphology, structure, acidity and particle size of fresh and spent Cr2O3catalysts were investigated by techniques such as XRD, SEM, TEM, BET and NH3-TPD. In addition, catalytic performance was evaluated for the dehydrofluorination of 1,1,1,3,3-pentafluoropropane (CF3CH2CHF2, HFC-245fa) to 1,3,3,3-tetra-fluoropropene (CF3CH=CHF, HFO-1234ze). The catalytic reaction rate of Cr2O3prepared by SCS method is as high as 6 mmol/h/g, which is about 1.5 times and 2 times higher than that of precipitated Cr2O3and commercial Cr2O3, respectively. The selectivity to HFO-1234ze for all the catalysts maintains at about 80%. Compared with commercial and precipitated Cr2O3, Cr2O3-SCS prepared by SCS possesses higher specific surface area and acid amount. Furthermore, significant change in the crystal size of Cr2O3prepared by SCS after reaction was not detected, indicating high resistance to sintering.
研究领域:
材料化学
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催化化学
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纳米材料科学
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环境友好化工
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氟化学
✓ 已验证
DOI
高影响因子
FUEL
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2023
·
IF 7.4
Yang Du,Shi-Qi Yang,Yun-Jie Li,Zhi-Bin Wang,Xing-Bao Wang,Zhen-Yi Du,Wen-Ying Li
Nickel-based catalysts have been broadly studied for the steam reforming of coal/biomass tar due to their inexpensiveness and good activity. Nevertheless, their industrial application has long been restricted by the deactivation induced by carbon deposition and Ni sintering in the reforming process. Herein, ordered mesoporous nickel-alumina catalysts with varying K contents were prepared. Their performance in steam reforming of toluene as a model compound of tar was evaluated to reveal the effects of K doping. Among them, the catalyst with 2 wt% K loading displayed the best catalytic activity and stability. Experimental and theoretical calculation results suggested that K doping enhances the water adsorption capability of the catalysts, which thereby reduces the amount and graphitization degree of carbon deposits. Moreover, the K doping reduces the acid amount of the support and thereby inhibits the formation of carbon deposits as well. However, K doping does not affect the reaction pathway of the catalysts in toluene steam reforming, and the main reaction intermediates detected with in-situ DRIFTS remain the carbonate groups. Furthermore, the confinement effects of the ordered mesoporous structures inhibit the sintering of Ni particles and the formation of carbon deposits. In addition, the influence of different spatial positions of K on the catalysts was explored. It was found that the K introduction via the one-pot solvent evaporation induced self-assembly method can suppress the loss of K from the catalysts.
研究领域:
催化
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化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 9
·e202203501
·
IF 2.1
Br. Yundi Zhang,Mingyu Cui,Yidong Zhang,Wei Xu,Min Wang,Rong Shao,Jianfei Ding
Graphical The PMD conversion, TBPM selectivity, yield and the catalytic stability were obviously improved on the nanocrystalline HZSM-5 (Z-1) prepared by supercritical hydrothermal synthesis, because it had more amount of framework tetrahedral Al species and the total acidity, higher surface area and pore volume than those of HZSM-5 (Z-2) prepared by conventional hydrothermal synthesis. The nanocrystalline HZSM-5 was synthesized by supercritical hydrothermal synthesis for the first time and investigated in catalytic esterification of pyromellitic dianhydride(PMD)and n-butanol to tetrabutyl pyromellitate(TBPM). The HZSM-5 prepared by conventional hydrothermal synthesis was also examined for comparison. The catalysts were studied using XRD, N 2 adsorption, NH 3 -TPD, Pyridine-adsorption FT-IR, SEM, [27] Al MAS NMRandCHNS analysis. According to the results of characterization, the supercritical hydrothermal condition was helpful to reduce the size of crystal particles and improve the crystallinity of HZSM-5, and shorten the crystallization time. The surface area, especially external surface area, and pore volume were increased, and the total acidity was increased. The strong acid sites were transformed into the weak acid sites, and the strength of weak and strong acid was weakened. The amount of framework tetrahedral Al species and Brönsted acid sites were increased. Therefore, the formation of coke was retarded, and thePMD conversion, the TBPM selectivity and the catalytic stability were obviously improved.
研究领域:
化学
·
催化
·
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）