INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Ne Ni,Ying Ouyang,Jianqiang Liu,Enhui Xing,Yibin Luo,Xingtian Shu
It was the thermostability and acidity of P precursors that influenced the interaction between P species and framework Al to determine the hydrothermal stability of P modified ZSM-5. With H3PO2 and NH4H2PO2 as P precursors, the P–Al interactions of P modified ZSM-5 samples calcined under different temperatures were systematically investigated by X-ray fluorescence, X-ray photoelectron spectroscopy, 27Al, and 31P MAS NMR spectroscopy, and temperature-programmed desorption of NH3 (NH3-TPD). With H3PO2 as the precursor, lower calcination temperature favored less self-polymerization of P species; however, obvious loss of phosphorus was observed during hydrothermal treatment. Conversely, higher calcination temperature tended to result in excessive interaction between P and framework Al for dealumination. Therefore, moderate interactions between P and framework Al were obtained over H3PO2 modified ZSM-5 calcined at 350 °C, which contributed to weaken the self-polymerization of P species. Compared with H3PO2, neutral NH4H2PO2 generated a relatively weaker P-zeolite interaction, which was less affected by the calcination temperature.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2022
·Vol. 105
·期 8
·5167-5177
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IF 4.186
Ruili Zhang,Delong Ma,Jianrong Wang,Yang Chen,Xun Hu
A detailed structural investigation of a series of phosphate laser glasses with composition x Bi 2 O 3 – y Al 2 O 3 –(100 − x – y )NaPO 3 ( x = 0, 10; y = 0, 5, 10, 15, 20) has been conducted using solid-state nuclear magnetic resonance (NMR) techniques and X-ray photoelectron spectroscopy (XPS). 31 P MAS NMR spectroscopy demonstrates that the addition of Bi 2 O 3 and Al 2 O 3 leads to the depolymerization of the phosphorus chain in the process of Q 2 → Q 1 → Q 0 . The various phosphorus species (Q n , n = 0, 1, 2) are identified by 31 P single pulse, 31 P{ 27 Al} rotational echo adiabatic passage double resonance, 31 P{ 27 Al} J-coupling-based heteronuclear multiple-quantum coherence, and 1D refocused INADEQUATE experiments. The results of 23 Na{ 31 P}, 31 P{ 23 Na}, 27 Al{ 31 P} rotational echo double resonance, and XPS consistently confirm that Na + , Al 3+ , and Bi 3+ ions are all bound by phosphorus tetrahedron [PO 4 ] 3− . No bond is formed between these glass modifiers. Based on the complementary evidence from previous experiments, comprehensive local structure models are developed for these Bi 2 O 3 –Al 2 O 3 –NaPO 3 glasses.
研究领域:
材料科学
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固体物理学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Yimin Zhang,Yun Zu,Ke Yan,Yuan Zhu,Yibin Luo,Enhui Xing,Qiang Li,Lijuan Song,Tan Li,Yi Mei,Xingtian Shu
In this work, a "bottom-up" strategy was proposed to one-step, in-situ synthesize P@ZSM-5 zeolites in a sodium-free system by elaborately self-designed tetrapropylphosphonium hydroxide as a new member of MFI-type zeolite organic templates inventory, and the interaction of phosphorus species with framework aluminum was investigated in detail. Multiple advanced characterizations confirm that the tetrahedrally-coordinated bidentate P IV -O 2 -Al IV structures are precisely customized and uniformly scattered in the zeolite channels. After experiencing harsh hydrothermal treatment (100 %H 2 O, 800 °C, 17 h), this new structure endows excellent hydrothermal stability of zeolite (crystallinity retention beyond 95 %) and reinforces its Brønsted acidity. Furthermore, methanol-to-propylene tests show that directly synthetic P@ZSM-5 zeolite performs extraordinarily long lifetime (180 h, WHSV = 1 h −1 ), enviable propylene selectivity (60.4 %) and propylene/ethylene ratio ( ca. 4.3) compared to the counterparts, which is benefited from encouragingly olefinic cycle pathway. These findings afford value-filled opportunities in novel catalyst production mode and understandings for phosphorus-zeolite chemistry . Synopsis -A "bottom-up" strategy was demonstrated to one-step, in-situ synthesize P@ZSM-5 zeolite in a sodium-free system by elaborately self-designed tetrapropylphosphonium hydroxide. The resultant P@ZSM-5 catalyst with hyperuniformly-stable bidentate P IV -O 2 -Al IV structures exhibited extraordinarily long lifetime (180 h) and enviable propylene selectivity (60.4 %).
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Feng Shi,Lili Hu,Yun Cui,Jinjun Ren
Glasses in the xLa2O3-yAl2O3-(100 – x – y)NaPO3 system were synthesized by a melt quenching method, where 0 ≤ x ≤ 7.5, y = 0 and x = 5, 5 ≤ y ≤ 15. The structures were characterized by advanced multinuclei solid-state nuclear magnetic resonance spectroscopy (SSNMR) and X-ray photoelectron spectroscopy (XPS). 31P MAS NMR spectroscopy indicates that the glass Q2 structure is depolymerized by La2O3 and Al2O3, forming multiple QxAln and QyLan phosphorus species, where n, x, and y represent the number of P–O–P, P–O–Al, and P–O–La bonds, respectively. The various phosphorus species were identified by the J-coupling effect based one and two-dimensional (1D and 2D) experiments such as 2D J-resolved, 1D refocused INADEQUATE and 1D 31P{27Al} J-coupling heteronuclear multiple quantum coherence (HMQC). La is used as a mimic to simulate the local structure of the luminescent rare earth ions. 139La wideband uniform rate smooth truncation quadrupolar Carr–Purcell–Meiboom–Gill (WURST-QCPMG) spectra show that the coordination number of La is dominantly nine, and some La atoms transfer to lower coordination with the addition of Al2O3. La, Al, and Na atoms exclusively bond to phosphorus tetrahedron PO4, which is evidenced by the 31P/23Na, 31P/27Al double resonance NMR, XPS, and the calculation of charge balance. However, the Al/P and La/P connection methods are much different based on the calculation of charge balance and bond number. Finally, comprehensive and novel local structure models are developed for these rare earth-doped aluminum phosphate glasses.
研究领域:
材料科学
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化学
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
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2020
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IF 2.929
Tongyao Zhao,Xuyang Zhang,Jinjun Ren
A series of glasses with the compositions of 10NaF-(90-x) NaPO 3 -xYF 3 ( x = 5, 10, 15 and 20 mol%) were prepared via the conventional melt-quenching method. The structures of these glasses were characterized by multiple advanced solid-state nuclear magnetic resonance (SSNMR) techniques. Multiple phosphorus species Q m nY were resolved at atomic level. Here, the value m and n denote the number of P–O–P bonds and the number of Y 3+ ion bounding to phosphorus oxygen tetrahedron, respectively, which were identified by two dimensional (2D) J -resolved spectroscopy. 19 F MAS spectra, 19 F↔ 23 Na and 19 F↔ 31 P rotational echo double resonance (REDOR) prove that F − ions are involved into the glass networks through Y-F•••Na and P-F•••Na linkages. The 31 P { 19 F} J -coupling based heteronuclear multiple quantum coherence ( J -HMQC) spectrum proves that F − ions selectively connect with Q 1 species. F − ions show significant preference to connecting with Y 3+ over P 5+ .
研究领域:
材料科学
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物理学
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DOI
高影响因子
GREEN CHEMISTRY
·
2022
·Vol. 24
·期 4
·1570-1577
·
IF 11.034
Ruixue Yangcheng,Jiansu Ran,Zhaohui Liu,Yuntong Cui,Jianjian Wang
Efficient production of high value-added chemicals and biofuels via low-temperature chemoselective HDO of lignin derivatives in water is still a challenge. Here, we construct a low-cost, active and stable Pd/PCE catalyst using phosphoric acid-modified commercial Celite (PCE) as the support, and this catalyst exhibits excellent activity in low-temperature HDO of vanillin as well as other lignin derivatives in water. The superior catalytic performance is due to the presence of P species on the surface of Pd/PCE, accelerating the selective conversion of the intermediate into the final product. Detailed experimental and mechanistic studies reveal that the rapid conversion of the intermediate to the final product proceeds via a free-radical process in an interfacial microenvironment created by intimate interacting between the P species and Pd NPs. The insights of this work provide a new low-cost catalytic system for efficient production of valuable chemicals and future biofuels from lignin derivatives.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
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IF 10.753
Gang Chu,Wangmin Wang,Jing Zhao,Dandan Zhou
Phosphoric acid-assisted pyrolysis (PAAP) is a pyrolysis technique with potential for the engineered and environmental application. Nevertheless, the volatilisation, immobilisation, and dissolution of phosphorus (P) species have been neglected during PAAP of lignocellulose. Therefore, we compared the transformation of P species with direct-pyrolysis and PAAP system, using multiple techniques including gas chromatography tandem mass spectrometry (GCMS) and 31 P nuclear magnetic resonance (NMR). It was also investigated that the properties of pyrogenic and modified carbons obtained from lignocellulose pyrolysis at 200–650 °C. As the temperature increased, volatile P species evolved into gas-phase during PAAP, inhibiting the formation of the macromolecular volatile components. Compared with pyrogenic carbons, modified carbons with more aromatic structures experienced a higher degree of dehydration and cyclisation via catalytic crosslinking reaction. PAAP system facilitated more generation of persistent free radical (PFR) below 500 °C and the attenuation of PFR signals was observed at 500–650 °C, which may be associated with the sequestration and elimination of P species between carbon matrix. Notably, three configurations of C 3 P O, C P O, and C O P were the major combinations of P and C elements on modified carbons. Increased gaseous P and decreased soluble P were observed with elevated temperatures in PAAP system. The species proportion of immobilised P clearly demonstrated the transformation of partial P species from inorganic to organic through pyrolysis. The immobilised P could serve as a potential sustained-release source participating in P biogeochemical cycles . These findings are fundamental for the technical design of lignocellulose pyrolysis.
研究领域:
环境科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Guosheng Li,Yu Ding,Xiaohan Li,Kunhong Li,Xinrui Yin,Liang Zhao,Shenyong Ren,Chunming Xu,Baojian Shen
Regulation of electronic structure of metal active phase for catalysts has been known as efficient in promoting its catalytic activity; however, manipulating the activity of catalysts via controllable metal active phase electronic structure is still challenging. A non-equilibrium electronic structure Fe-based bulk catalyst has been developed via controllably adding P species, where the non-equilibrium electronic structure of Fe species is formed through the electron transfer from the Zn species through the P electronic channel. As a result, the catalytic activity of the modified Fe-based bulk catalysts has increased by 24.4–50.4%. Meanwhile, the sulfurization degree (SD) of the modified Fe-based bulk catalysts has increased by 5.6–25.9%. In addition, the HDS reaction rate constant ( k HDS ) has increased by about 2.0 times, and the DDS reaction rate constant ( k DDS ) has increased by about 2.4 times. The P modifying can regulate the directional transfer of unpaired free electrons between Fe and Zn species to form a more non-equilibrium electronic structure of Fe species, which can reduce the energy barrier of the C–S bond adsorbed on the P-modified Fe-based bulk catalysts. Importantly, the P species can be used as an active site to adsorb S-containing compounds in the modified Fe-based bulk catalysts, which is conducive to generating more coordinatively unsaturated sites (CUSs). The former can promote the formation of the more non-equilibrium electronic structure of Fe species, and the latter can adjust the adsorption active site of S-containing on the catalyst surface. Therefore, an electron transfer channel is formed among Fe, Zn, and P species, and another one is formed among Fe, P, and S-containing compounds, which form a dual-channel electron transfer behavior. Furthermore, the specific surface area, total pore volume, and reducibility of the modified Fe-based bulk catalysts have also shown varying degrees of improvement via the controllable addition of P species.
研究领域:
催化
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材料科学
·
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）