CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2021
·
IF 3.171
Xin Yong,Hong Chen,Huawang Zhao,Miao Wei,Yingnan Zhao,Yongdan Li
The effects of SO 2 on an one-pot synthesized Cu-SSZ-13 catalyst for selective reduction of NO x by NH 3 were examined. The addition of SO 2 inhibited NO x conversion significantly below 300 °C, while no effect on NO x conversion was observed above 300 °C. TGA, TPD , and XPS results showed that the deactivation was caused by the formation of (NH 4 ) 2 SO 4 , SO 2 chemisorption on the isolated Cu 2+ ion sites, as well as the formation of CuSO 4 -like species. Among them, the site-blocking effect of (NH 4 ) 2 SO 4 on Cu 2+ was the primary reason for deactivation. Fortunately, 89% of deNO x activity of the poisoned catalyst was recovered after thermal treatment at 500 °C in air, where (NH 4 ) 2 SO 4 was completely decomposed. The activity was further recovered with regeneration temperature increasing to 600 °C, removing the adsorbed SO 2 on the Cu 2+ sites. The regeneration at 600 °C could not recover the activity completely, because of the high stability of CuSO 4 -like species.
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 HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Hongyuan Xi,Song Zhou,Jinxi Zhou,Zhao Zhang
The novel combined system using Na 2 S 2 O 8 /urea was used to simultaneously absorb nitric oxide and sulfur dioxide emissions from marine diesel engines as well as inhibit the formation of nitrate in cleaning wastewater to meet the increasingly stringent requirements of regulations. The influences of reaction temperature, Na 2 S 2 O 8 concentration, urea concentration, SO 2 concentration, NO concentration and pH value on SO 2 removal efficiency, NO removal efficiency and nitrate concentration were investigated. The experimental results showed that different reaction temperatures had different influences on SO 2 removal efficiency, NO removal efficiency and nitrate concentration. An increase in Na 2 S 2 O 8 could improve the absorption of NO. The addition of urea could effectively improve the removal efficiency of NO and reduce the nitrate concentration. The removal efficiencies of 1000 ppm NO and 1000 ppm SO 2 achieved 100 % with 0.2 mol/L Na 2 S 2 O 8 and 2 mol/L urea at 70℃, and the nitrate content was 8.56 mg/L which was far lower than the regulatory requirement of 60 mg/L. The acidic condition (pH ≤ 5.5) not only facilitated the absorption of NO but also reduced the generation of nitrate. According to the experimental results, the novel combined system was promising to be applied to the control technology of marine diesel engine exhaust.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Applied Sciences-Basel
·
2018
·Vol. 8
·期 1
·95
·
IF 1.689
Chengzhi Wang,Cheng Zhang,Yonggang Zhao,Xin Yan,Peng Cao
Honeycomb cordierite-based Mn–Ce/Al2O3catalysts were prepared by the impregnation method and used for low-temperature selective catalytic reduction (SCR) of NOxwith NH3, with and without SO2and/or H2O in a homemade fixed-bed tubular reactor. The catalyst reached nearly 80% NOxconversion at 100 °C in the absence of SO2. However, SO2reduces the catalytic activity (80% to 72%) of the honeycomb cordierite-based Mn–Ce/Al2O3catalysts under identical conditions. This finding demonstrated that the catalyst exhibited high activity at low temperature and excellent SO2resistance in the presence of 50 ppm SO2. The fresh and sulfated honeycomb cordierite-based Mn–Ce/Al2O3catalysts were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), N2adsorption–desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry and differential thermal analysis (TG-DTA), and Fourier transform infrared (FT-IR) spectroscopy. Characterization results indicated that the deactivation by SO2was primarily the result of the deposition of ammonium hydrogen sulfate and sulfated CeO2on the catalyst surface during the SCR process. The formed sulfates depressed the catalytic activity via the blocking of pores and the occupation of active sites. Additionally, the competitive adsorption between SO2and NH3always decreased the catalytic activity.Keywords:Mn–Ce/Al2O3catalyst;low temperature selective catalytic reduction;honeycomb cordierite;SO2resistance
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
·
2022
·
IF 9.965
Minghu Zhao,Jiuhu Zhao,Ran Ding,Rongshu Zhu,Haiyan Li,Zhi Li,Jingwen Zhang,Yongji Zhu,Huiying Li
The existence of sulfur dioxide and water vapor in the flue gas generated from waste-to-energy stations could lead to catalyst deactivation , which has adverse effects on NO x removal. It is thus particularly important to study the reaction mechanism of catalyst resistance to poisoning. Herein, we report the mechanism of In-Co 3 O 4 -Ga 2 O 3 /H-Beta catalyst to SO 2 and H 2 O resistance in the selective catalytic reduction (SCR) of NO x by CH 4 . The catalyst could achieve 74.6% NO x removal efficiency in the presence of 100 ppm SO 2 and 5% H 2 O. In this catalyst, Co 3 O 4 is attributed to enhancing the reversible poisoning of SO 2 and CH 4 activation and increasing the number of Brønsted acid sites by decomposing H 2 O. However, the InO + active center was still eroded by a small amount of water vapor, leading to a reduction in NO x removal efficiency. The addition of Ga 2 O 3 primarily provided an important intermediate NO 2 for CH 4 -SCR reaction and reduced the aggregates of Co 3 O 4 to increase the exposure of indium sites, and could reduce a part of SO 2 to S 2− . This study provides a good candidate for preparing catalysts with superior resistance towards SO 2 and H 2 O for CH 4 -SCR.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Qiao Ding,Ning Li,Bo Wu,Qing Cheng,Qi Zhao,Tong Liu,Rui Wang,Deyu Li
In this study, SO 2 was used to chemically modify the commonly used leveling agent polydimethyldiallylammonium (PD) in through-hole electroplating, resulting in a more effective leveling agent, PDS, which improved the throwing power (TP), leading to through-hole circuit boards with better metal coverage in difficult-to-reach areas. Furthermore, theoretical and experimental studies were conducted to understand how the −SO 2 structure influences the leveling ability of the leveling agent. The study demonstrates that the −SO 2 -modified additive significantly enhances the copper plating process, resulting in thicker and more uniform deposits in through-holes, which are critical for ensuring high-quality circuit boards.Additionally, this study elucidates the mechanism of action of the leveling agent on the copper surface, providing theoretical support for the development of copper plating leveling agents. The leveling ability differences between the leveling agents PD and PDS were investigated using Cyclic Voltammetry, constant current method, and Electrochemical Impedance Spectroscopy. Additionally, the optimal concentrations of the additives were determined. Quantum chemical calculations were employed to analyze the electrostatic potential, HOMO/LUMO orbitals, and differential charge density on the Cu (111) surface for both leveling agents. These theoretical analyses provided insights into the reasons behind the differing leveling abilities of the two agents.
研究领域:
材料科学
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电化学
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理论化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
·
IF 22.1
Ning Luo,Fengyu Gao,Hengheng Liu,Tingkai Xiong,Jiajun Wen,Erhong Duan,Chengzhi Wang,Shunzheng Zhao,Honghong Yi,Xiaolong Tang
Developing effective and stable catalysts for low-temperature selective catalytic reduction (SCR) of NO x remains challenging. Herein, we constructed a hierarchical structure by loading CoMn 2 O 4 onto Ti-doped CeO 2 , that CoMn 2 O 4 /CeTiO x catalyst has shown superior deNO x activity (>95% at 100–225 °C), prominent reaction activation energy (28.8 ± 0.9 kJ mol −1 ) and outstanding stability (>75% at 100–200 °C within H 2 O and SO 2 ). The “low-temperature active sites” and “dual anti-poisoning sites” contribute to excellent activity and stability. Firstly, the hierarchical structure boosts generation of active metal-support interface, which is conducive to oxygen migration (including adsorbed oxygen (O ads ), lattice oxygen (O lat ) and oxygen vacancy (O v )) and metal charge transfer (Mn 2+/3+ +Ce 4+ ↔Mn 3+/4+ +Ce 3+ , Ti 4+ +Ce 3+ ↔Ce 4+ +Ti 3+ ). This is the key to breaking through the limits of catalytic activity stability. Secondly, enhanced surface acidity favors NH 3 adsorption and activation, which accelerates -NH 2 /-NH concatenate with NO x through Eley-Rideal mechanism to generate N 2 and H 2 O. Thirdly, the dual strong SO 2 affinity sites by Ti-induced CeO 2 crystal reconstruction retard the active center affected by the sulfate species, which contributes to striking stability. This work highlights the importance of design of isolated active sites to improve SO 2 and H 2 O endurance.
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
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2018
·
IF 4.841
Jiahong Zhu,Yingjie Xu,Xiao Feng,Xiao Zhu
To get a better understanding of the effect of physicochemical properties and microstructure on SO 2 absorption behavior of DESs with different molar ratios of EmimCl and EG (from 2:1 to 1:2), densities ( ρ ), viscosities ( η ), speeds of sound ( u ), refractive indices ( n D ), and thermal decomposition temperatures ( T d ) of EmimCl-EG DESs were measured and used to obtain the other derived properties, such as thermal expansion coefficient ( α p ) and activation energy for viscous flow ( E η ). Moreover, FT-IR spectra and in situ variable-temperature NMR spectroscopy were employed to study the microstructures of DESs. Based on physicochemical and spectroscopic properties, the influence of the concentrations of EmimCl on the interactions in DESs was explored to be associated with their SO 2 absorption behavior. The results show that the interactions between Emim + and Cl − of EmimCl is gradually weakening with increasing the concentration of EG in DESs by forming of hydrogen bond interaction of O H⋯Cl − , resulting in a decrease of ρ , η , u , n D , and T d of DESs, and hindering the charge–transfer interaction of SO 2 with Cl − and deceasing SO 2 capture capacity. Moreover, the SO 2 absorption capacity of DESs is proportional to their ρ and E η , respectively.
研究领域:
化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2021
·Vol. 11
·期 3
·314
·
IF 4.146
Lusha Zhou,Jinkun Guan,Chenglong Yu,Bichun Huang
The ethanol dispersion method was employed to synthesize a series of MnOx/SAPO-34 catalysts using SAPO-34 with the hierarchical pore structure as the zeolite carrier, which were prepared by facile acid treatment with citric acid. Physicochemical properties of catalysts were characterized by XRD, XPS, BET, TEM, NH3-TPD, SEM, FT-IR, Py-IR, H2-TRP and TG/DTG. NH3-SCR performances of the hierarchical MnOx/SAPO-34 catalysts were evaluated at low temperatures. Results show that citric acid etching solution at a concentration of 0.1 mol/L yielded a hierarchical MnOx/SAPO-34-0.1 catalyst withca.15 wt.% Mn loading, exhibiting optimal catalytic activity and SO2tolerance at low temperatures. Almost 100% NO conversion and over 90% N2selectivity at 120 °C under a gas hourly space velocity (GHSV) of 40,000 h−1could be obtained over this sample. Furthermore, the NO conversion was still higher than 65% when 100 ppm SO2was introduced to the reaction gas for 4 h. These could be primarily attributed to the large specific surface area, high surface acidity concentration and abundant chemisorbed oxygen species provided by the hierarchical pore structure, which could also increase the mass transfer of the reaction gas. This finding suggests that the NH3-SCR activity and SO2poisoning tolerance of hierarchical MnOx/SAPO-34 catalysts at low temperatures can be improved by controlling the morphology of the catalysts, which might supply a rational strategy for the design and synthesis of Mn-based SCR catalysts.
研究领域:
催化化学
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环境科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Wei Chen,Juan Zheng,Yarong Fang,Yutao Wang,Jinpeng Hu,Yuhua Zhu,Xiaoxiao Zhu,Weihao Li,Qian Zhang,Chuanqi Pan,Baojian Zhang,Xiaofeng Qiu,Sibo Wang,Shuang Cui,Jinlong Wang,Jinsong Wu,Zhu Luo,Yanbing Guo
Typically, SO2 unavoidably deactivates catalysts in most heterogeneous catalytic oxidations. However, for Pt-based catalysts, SO2 exhibits an extraordinary boosting effect in propane catalytic oxidation, but the promotive mechanism remains contentious. In this study, an in situ-formed tactful (Pt–S–O)-Ti structure was concluded to be a key factor for Pt/TiO2 catalysts with a substantial SO2 tolerance ability. The experiments and theoretical calculations confirm that the high degree of hybridization and orbital coupling between Pt 5d and S 3p orbitals enable more charge transfer from Pt to S species, thus forming the (Pt–S–O)-Ti structure with the oxygen atom dissociated from the chemisorbed O2 adsorbed on oxygen vacancies. The active oxygen atom in the (Pt–S–O)-Ti active structure is a robust site for C3H8 adsorption, leading to a better C3H8 combustion performance. This work can provide insights into the rational design of chemical bonds for high SO2 tolerance catalysts, thereby improving economic and environmental benefits.
研究领域:
催化化学
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环境科学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2019
·
IF 6.35
Xu You,Junjie Wu,Yuwu Chi
Recently emerging perovskite quantum dots (PQDs) with several excellent optical properties, such as quantum efficiency, narrow band emission, and tunable emission wavelength, have promising applications in solar cells and light emitting diodes. However, relatively rare applications of PQDs can be found in the field of sensing, mainly due to the very easy degradation of PQDs upon exposure to water or ambient humidity. In this work, for the first time CH3NH3PbBr3 PQDs were encapsulated into superhydrophobic silica aerogels (AGs) to protect PQDs from being degraded by water. The synthesized PQDs@AGs not only maintain the strong fluorescence emission activity of PQDs but also show excellent stability in the presence of water. Additionally, PQDs@AGs have abundant pores making them very suitable for gas sensing. For improving sensing performances, 3D-printing technology is introduced into gas cell design and fabrication for the first time. Finally, a novel, sensitive, selective, and reversible fluorescence sensor for SO2 gas based on the PQDs@AGs functional material and the 3D-printed gas cell has been developed.
研究领域:
材料科学
·
化学传感器
·
光学材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Xiaocai Meng,Jianying Wang,Haichao Jiang,Xinle Shi,Yongqi Hu
A functional 2-ethyl-4-methylimidazole alanine ([Emim][Ala]) ionic liquid was synthesized. Its density, viscosity, and surface tension were measured at the temperature range from 293.15 to 343.15 K at atmosphere pressure. The solubility of SO2 in pure [Emim][Ala] ionic liquid and the binary mixture of [Emim][Ala] and water was also investigated. The absorption\desorption mechanism of SO2 was proposed on the basis of 13C nuclear magnetic resonance and Fourier transform infrared spectroscopy. Results showed that SO2 was captured as ammonia sulfonic acid ester by pure [Emim][Ala], while for the binary mixture of [Emim][Ala] and water, the final product of SO2 absorption is alanine and [Emim]+[HSO3]−/[Emim]+2[SO3]2–.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2022
·
IF 5.477
Kaiwen Ni,Yuewang Peng,Geyu Dai,Huawang Zhao,Zhiwei Huang,Xiaomin Wu,Guohua Jing,Wei Feng,Ye Yuan
Background Ammonia bisulfate (ABS) deposition on the active sites of the catalyst surface is the main reason for SO 2 poisoning in low-temperature NH3-selective catalytic reduction (SCR). Accelerated ABS decomposition efficiently enhances the SO 2 resistance. Methods In this work, ceria was specifically chosen to decorate V 2 O 5 -WO 3 /TiO 2 catalyst (Ce-VW/Ti) to activate ABS decomposition in low-temperature NH 3 -SCR. Significant findings The optimal 7Ce-VW/Ti catalyst accelerated the decomposition of ABS and had superior SO 2 tolerance at 250°C. The additive CeO 2 improved the specific surface area and surface acidity, favoring the NH 3 -SCR catalytic activity. ABS was preferentially deposited on the additive CeO 2 on the surface of the 7Ce-VW/Ti catalyst and generated cerium sulfate, eventually protecting the active V 2 O 5 sites and TiO 2 support. Moreover, high quantity of V 5+ and charge transfer between active species V 2 O 5 and support TiO 2 could be maintained due to CeO 2 protection, subsequently maintaining the high NH 3 -SCR performance and enhancing the SO 2 tolerance.
研究领域:
催化
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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）