CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Jingang Wang,Jianbo Zhang,Cheng Xing,Taosheng Jin,Jinpeng Liu,Meiting Ju,Xuejiao Tang
Phosphorus (P) poisoning of NH 3 -SCR catalysts is inevitable in application of NO x abatement of diesel exhaust. The distinct effects on Cu-SSZ-13 of P from different precursors (H 3 PO 4 and (NH 4 ) 2 HPO 4 ) were figured out and the mechanism was further investigated. P-poisoned Cu-SSZ-13 (Si/Al = 6) catalysts were prepared and characterized using N 2 adsorption, X-ray powder diffraction (XRD), scanning electron microscope with energy-dispersive X-ray spectroscopy mapping (SEM-EDX), ammonia temperature-programmed desorption (NH 3 -TPD), X-ray photoelectron spectroscopy (XPS), hydrogen temperature programmed reduction (H 2 -TPR), electron paramagnetic resonance (EPR) and 27 Al solid-state magic angle spinning nuclear magnetic resonance spectroscopies ( 27 Al NMR). Significant enhancement of high-temperature activities (400–600 °C) were observed for the catalysts with P loading of 0.3–0.9 wt%, since the appropriate incorporation enabled to bind P atoms to CuO x in remained framework. However, the high P content of 1.5 wt% resulted in a detrimental effect on framework to induce the accumulation of Cu species. Interestingly, the dominant P from H 3 PO 4 was inclined to directly attack the framework Al leading to more severe dealumination, while the P from (NH 4 ) 2 HPO 4 interacted with Cu 2+ to form copper phosphate with more Cu 2+ migrating to the surface of the catalyst which promoted the NO x conversation at each active site resulting in the low-temperature catalytic activity unchanged. So, control of the P/Cu and form of P is capable of preventing P poisoning and unlocks the potential of Cu-SSZ-13 in exhaust treatment.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
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IF 9.965
Kunli Song,Shuqi Zhao,Zhenguo Li,Kaixiang Li,Yurong Xu,Yijun Zhang,Yonghong Cheng,Jian-Wen Shi
SSZ-13 has been commercialized as a catalyst in diesel engines for the selectivity catalytic reduction of nitrogen oxides (NO x ) with ammonia (NH 3 -SCR), but the catalyst is facing the problem of poisoning. Herein, two well-designed catalysts, Cu-SSZ-13 and cerium (Ce) doped Cu-SSZ-13 are synthesized, and their tolerance to zinc (Zn) and phosphorus (P) poisoning alone and together are explored in detail. The research found that Zn and P poisoning alone leads to the destruction of Cu-SSZ-13 structure, resulting in the decline of denitration (de-NO x ) performance following the mechanism dominated by Eley-Rideal (E-R). Surprisingly, it is found that zinc phosphate particles are formed at inactive sites on the surface of Cu-SSZ-13 in the presence of Zn and P together, which protects the active sites, enhances the adsorption of nitric oxide. As a result, the excellent de-NO x performance of Cu-SSZ-13 is well maintained following the dual mechanism of E-R and Langmuir-Hinshelwood (L-H). In addition, the introduction of Ce stabilizes the active sites, so as to improve the de-NO x performance and the poisoning tolerance of Cu-SSZ-13. This work deeply analyzes the reasons of Zn and P poisoning and the positive effect of Ce on Cu-SSZ-13, which provides ideas for improving the poisoning tolerance of Cu-SSZ-13 and promotes the further application.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Catalysis
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2021
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IF 13.084
Dongdong Chen,Huarong Lei,Wuwan Xiong,Ying Li,Xiang Ji,Jia-Yue Yang,Baoxiang Peng,Mingli Fu,Peirong Chen,Daiqi Ye
Phosphorus (P) originating from lubricant oil additives or biofuels is an emerging chemical poison in catalytic systems for automotive exhaust after-treatment. Here, we demonstrate that P-poisoning led to severe deactivation of small-pore Pd-SSZ-13 zeolites (with CHA framework) as passive NOx adsorbers (PNA) and CO oxidation catalysts for cold-start exhaust purification applications. Deactivation mechanisms of P-poisoning were unraveled by comparatively examining the P-free and P-loaded Pd-SSZ-13 zeolites using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance (NMR), temperature-programmed reduction by hydrogen (H2-TPR), CO pulse adsorption, temperature-programmed desorption using NH3 as a probe molecule (NH3-TPD), ultraviolet/visible light (UV/vis) spectroscopy, and in situ diffuse relectance infrared Fourier transform spectroscopy (DRIFTS). The loss of isolated Pd sites─namely, [Pd(OH)]+ and Pd2+ (located in the eight- and six-membered rings of CHA framework, respectively)─was revealed to be largely responsible for the deactivation of Pd-SSZ-13 in passive NOx adsorption and catalytic CO oxidation. In situ DRIFTS studies using NO or CO as a probe molecule suggest that [Pd(OH)]+ was more susceptible to P-poisoning than Pd2+. Specifically, P-poisoning led to a migration of [Pd(OH)]+ from cationic exchange sites to the zeolite surface, forming inactive metaphosphate (i.e., [Pd(OH)]+PO3–) and bulk PdOx species at high temperatures. In contrast, P-poisoning of Pd2+ sites proceeded via a sequential transformation to [Pd(OH)]+ first, and then to [Pd(OH)]+PO3– and bulk PdOx. This study provides a comprehensive mechanistic understanding on the deactivation of Pd-SSZ-13 by P-poisoning, and may guide the design of high-performance, phosphorus-resistant Pd-zeolite catalysts for cold-start exhaust after-treatment.
研究领域:
催化材料
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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
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
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2023
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IF 4.6
Ning Fan,Qian Li,Yuan Liu,Bohua Ma,Meng Li,Dongfeng Yin
Purpose Organophosphorus compounds (OPs) is a serious threat to human health and life safety, but because of the existence of blood-brain barrier, most of the therapeutic drugs cannot enter the center, reactivate centrally located toxic acetylcholinesterase (AChE), it is urgent to find an efficient treatment method. Methods The c(RGDyK) cyclic peptide modified HI-6-loaded brain targeting liposomes [c(RGDyK)-PEG 2000 HI-6-lipo] were prepared by ammonium sulfate gradient method. The in vitro blood-brain barrier (BBB) model was established, and the function of the liposomes was evaluated. The animal model of DDVP poisoning was established, and the central toxic enzyme reactivation ability of c(RGDyK)-PEG 2000 HI-6-lipo by both the intravenous and nasal administration route was verified. Results The HI-6-loaded liposomes with brain targeting function were successfully synthesized and prepared with high encapsulation efficiency (70.23 ± 2.18%), drug loading (2.86 ± 0.07)%, average particle size 242.9 nm (polydispersion index 0.149), and ζ potential -16.2 mV. Combined with the in vitro and in vivo studies, the c(RGDyK)-PEG 2000 HI-6-lipo has better ability to cross the BBB. In addition, compared with intravenous injection, nasal administration was proved to be more effective against organophosphorus poisoning, and the reactivation rate of brain acetylcholinesterase reached (26.19 ± 7.70)%. Conclusion The prepared c(RGDyK)-PEG 2000 HI-6-lipo has a better ability to cross BBB. Nasal administration, as a way to bypass the BBB and directly deliver drugs into the brain, effectively improves the bioavailability of HI-6 in the brain. This study holds promise by providing a non-invasive approach to deliver water-soluble oxime antidote into the brain and reactivate central acetylcholinesterase via the naso-brain route.
研究领域:
药剂学
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毒理学
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神经科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2020
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IF 6.785
Lan Guo,Ya-Jie Zhang,Yong-Liang Yu,Jian-Hua Wang
Butyrylcholinesterase (BuChE), the primary source of serum cholinesterase activity, is an indispensable biochemical marker for clinical diagnosis of liver function and organophosphorus poisoning. The requirement for bulky and expensive instruments represents a huge hindrance for point-of-care testing (POCT) of BuChE, especially in resource-limited settings. Herein, an easy-operated, economic, and portable photothermal (PT) biosensing platform for high-throughput BuChE detection was rationally designed. BuChE could “light up” the PT signal through in situ generation of Prussian blue (PB) by MIL-53 (Fe), which allowed us to translate biological signals into temperature signals. Such temperature change signals could be monitored at high throughput (six samples for a single measurement) by a miniature self-made integrated PT device via combining separable 96-well plates, a three-dimensional (3D) printed sample bracket, 808 nm lasers, and thermometers, satisfying the requirement for rapid on-site detection in a large batch with low cost. In addition, the large specific surface area, 3D network structure, and high porosity of MIL-53 (Fe) offered a beneficial platform for its reaction with enzymatic hydrolysate, resulting in high sensing sensitivity and low detection limit (0.3 U L–1), which was at least 20 000 times lower than the normal human serum BuChE activity. This facile, affordable, and broad applicability PT sensing platform provides a beneficial reference for the rational design of other disease diagnostic approaches suitable for POCT.
研究领域:
生物化学
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分析化学
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医学诊断
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2021
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IF 4.821
Zerui Ma,Lili Cao,Yifei Xing,Anrui Feng,Peng Zhang,Wei Li,Hailiang Nie,Yu-e Shi,Zhenguang Wang
Butyrylcholinesterase (BChE), a regulator for the cholinesterase activity in serum, is an important index for clinical diagnosis of organophosphorus poisoning and liver related disease. However, the assays for BChE activity are highly dependent on expensive and bulk equipment and professional operators, which limits its straightforward and portable detection. In this work, we proposed a straightforward and sensitive photothermal assay for the detection of BChE activity, avoiding the use of expensive instrument, professional operators, and separation process. Polydopamine (PDA) nanoparticles can be produced through the oxidation of dopamine by MnO 2 nanosheets, which show a rather strong photothermal features. Hydrolyzation of substrate into thiocholine and butyrate happens after introducing BChE. The generated thiocholine and butyrate inhibit the formation of PDA nanoparticle through reducing MnO 2 into Mn 2+ and creating an acidic environment, respectively. Those effects lead to the decreasing of photothermal efficiency of the reaction system, resulting in the decreasing on temperature change. Quantitative detection of BChE activity is achieved by recording the temperature change of system, using a common device, with a limit of detection of 40.65 U/L calculated. The presented results provide a clue for developing straightforward and portable photothermal assay for BChE, which shows great potential for their clinical applications.
研究领域:
生物化学
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分析化学
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纳米技术
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临床诊断
✓ 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）