FUEL
·
2025
·
IF 7.5
Jie Gao,Zijun Ran,Jingyu Ran,Xin Huang,Chuan Ma,Yunlin Shao
The catalysts utilized for low-temperature catalytic oxidation of Hg 0 from flue gas typically suffer from issues related to H 2 O and SO 2 poisoning. This study focused on doping modification of La 0.875 Ce 0.125 CoO 3 perovskite with promoters and conducted a thorough investigation on the H 2 O and SO 2 resistance through characterization and DFT methods. Experimental results demonstrated that the LCeCO/30 wt% ZrO 2 possessed optimal H 2 O and SO 2 resistance. Under high sulfur (1500 ppm SO 2 ) and high humidity (10 % H 2 O(g)) conditions, it maintained approximately 91 % Hg 0 removal efficiency after thermal regeneration cycles. Characterization results indicated that ZrO 2 doping facilitated the formation of three-dimensional macroporous structure and protected active Co 3+ sites on the surface. Based on DFT calculations, the H 2 O poisoning is attributed to competitive adsorption between H 2 O(g) and Hg 0 on the active sites. Also, the SO 2 poisoning occurs due to competitive adsorption of SO 2 and the toxicity of sulfates to the surface active sites. Meanwhile, ZrO 2 doping can lower the adsorption energies of H 2 O(g) and SO 2 by modifying their adsorption configuration, thus weakening the competitive adsorption of H 2 O(g) and SO 2 with Hg 0 . Overall, LCeCO/ZrO 2 is a promising Hg 0 removal catalyst with superior H 2 O and SO 2 resistance.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Peipei Zhao,Mingyu Guo,Qingling Liu,Lijun Fan,Jinfeng Han,Caixia Liu,Na Ji,Chunfeng Song,Degang Ma,Zhenguo Li
A series of Mn a Zr b Cr c O x catalysts with different Cr/Mn molar ratios were synthesized via co-precipitation for the selective catalytic reduction of NO x with NH 3 (NH 3 -SCR). It was found that a Mn 5 Zr 2 Cr 2.5 O x catalyst with a Mn:Zr:Cr ratio of 5:2:2.5 exhibited excellent low-temperature activity and the best levels of H 2 O resistance at a high weight hourly space velocity (WHSV) of 54,000 ml/(h·g). NO conversion levels were measured as greater than 87% within a temperature range of 150–250 °C, and catalytic performance levels reached 90% even 50 h after reactions occurred in the presence of 15% H 2 O at 230 °C. The characterization results show that strong interactions occurring between Mn, Zr and Cr oxides and higher quantities of Mn 4+ and Lewis acid sites improved the redox properties and facilitated H 2 O resistance. In situ diffuse reflectance infrared Fourier transform spectra ( in situ DRIFTS) show that coordinated NH 3 on Lewis acid sites and bidentate nitrates play important roles in SCR reactions and that such reactions follow both Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) mechanisms. The competitive adsorption of H 2 O and NO may be the main cause of the adverse effects of H 2 O on catalytic performance.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2021
·
IF 5.706
Huansheng Tan,Shibo Ma,Xiaoyu Zhao,Yushi Li,Chen Zhao,Yujun Zhu
Bimetallic W a CeO x (a = 0.06, 0.12, 0.18, 0.24) catalysts were synthesized for selective catalytic reduction of NO x with NH 3 (NH 3 -SCR). The influences of W on structure, activity and surface properties were investigated by XRF, XRD, Raman, TEM, N 2 adsorption-desorption, H 2 -TPR, O 2 /NH 3 /SO 2 -TPD, XPS, and in-situ DRIFTS. The characterization results show that the W/Ce ratio has a great effect on the NH 3 -SCR activity. The different catalytic activities of W a CeO x are mainly attributed to the acidity change, especially the increase of B-acid content plays a major role in enhancing low temperature activity. W 0.18 CeO x exhibits excellent low-temperature NH 3 -SCR activity, SO 2 /H 2 O resistance and N 2 selectivity with a broad activity window (190–490 °C) with 5%H 2 O. Moreover, good activity window (235–460 °C) can be maintained even the catalyst treated with 5% H 2 O at 800 °C for 12 h, showing especial hydrothermal stability. Thus, it can be summarized that W 0.18 CeO x is regarded as outstanding catalyst for low-temperature NH 3 -SCR of NO.
研究领域:
催化化学
·
环境科学
✓ 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
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2021
·
IF 6.064
Bichun Huang,Hansun Fang,Huajun Huang,Meijuan Lu,Chenglong Yu
A one-pot synthetic method was used to prepare copper (Cu)-modified manganese (Mn)-rich MnSAPO-34 catalysts, which were then used for NO x removal from stationary-source flue gas. The addition of Cu to these Mn-rich MnSAPO-34 catalysts significantly enhanced their low temperature (LT) selective catalytic reduction (SCR) activity and H 2 O resistance. The Mn 0.4 Cu 0.05 SAPO-34 catalysts demonstrated excellent LT NH 3 -SCR activity, with NO x removal being >90% from 160 to 300 °C. In addition, Mn 0.4 Cu 0.05 SAPO-34 catalysts exhibited high H 2 O resistance. This excellent performance was ascribed to strong synergistic effects between Mn 4+ and isolated Cu 2+ species in Mn 0.4 Cu 0.05 SAPO-34 catalysts, leading to suitable redox ability. The results of in situ FT-IR analysis indicated that LT-SCR reactions mainly proceeded by an Eley–Rideal reaction pathway at 200 °C in Cu-modified manganese-rich MnSAPO-34 catalysts. Thus, Mn 0.4 Cu 0.05 SAPO-34 was considered as a promising candidate for NO x removal from flue gas of stationary sources at low temperatures.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Jiayi Qi,Xingkun Qi,Yan Pan,Junshuo Cui,Ying Xiong,Weijun Shan,Haibiao Yu
Sm 0.06 Ni with excellent H 2 O resistance for eliminating N 2 O was prepared by co-precipitation method. Research indicated that the introduction of Sm into Sm 0.06 Ni has the following effects: (1) Sm species (Sm 2 O 3 ) highly dispersed on the surface of Sm 0.06 Ni catalyst, which not only decreased the crystallite size of NiO, but also produced a certain number of edge dislocations and defects. (2) Sm 2 O 3 weakened the Ni-O band and increased the number of active sites. (3) The redox cycle of Ni 2+ + Sm 3+ ↔ Ni 3+ + Sm 2+ was formed on the surface of Sm 0.06 Ni during the reaction. Based on the above changes, Sm 0.06 Ni exhibited superior catalytic performance and much lower E a for the reaction compared with pure NiO. Over Sm 0.06 Ni, the TOF at 350 ℃ was 4.1 × 10 −3 s −1 , 37 times of that over pure NiO. More importantly, Sm 0.06 Ni exhibited excellent H 2 O resistance performance under submitted real reaction conditions, about 76 % N 2 O conversion can be obtained at 400 ℃.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Linjia Li,Yiran Zhang,Xiaochao Wang,Junfeng Lu,Jiaqi Feng,Shu Zhao,Wei Qiu,Zhen Huang,He Lin
Integrated carbon capture and utilization (ICCU) technology based on Ca-Ni-based dual-function materials (DFMs) is an important carbon reduction measure. However, the severe performance degradation of DFMs caused by H 2 O is a challenge for ICCU. This study aims to improve the H 2 O resistance of Ce-doped Ni-Ca-based DFMs by Mg-Y co-doping. After 10 cycles with H 2 O, the carbon capture capacity, methane yield, and methane production rate were maintained at 11 mmol/g, 10.5 mmol/g, and 121.18 μmol/g·min, respectively. Changing the water vapor content (0 ∼ 10 %) has little effect on its performance. Characterizations (XRD, TEM, XPS, H 2 -TPR, CO 2 -TPD, NH 3 -TPD, H 2 -TPSR, and in-situ DRIFTS) and experiments (carbonation and conversion by H 2 O experiments) revealed a directional induced hydrogen spillover mechanism: The strong interactions of Ni-Mg and Ni-Y reduce the particle size and inhibit agglomeration; meanwhile, H 2 O can activate the Y-doped Ni-based catalyst in the carbonation process, inducing hydrogen spillover into the methanation reaction path during the subsequent conversion process, where Mg-promoted generated formaldehyde species act as a vital intermediate. It provides a novel idea to enhance the H 2 O resistance of DMFs to achieve stable ICCU performances.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 23
·8086-8093
·
IF 5.721
Haoxi Jiang,Debin Kong,Ying Niu,Sheng Wang
MnO2–CoOX catalysts with different Mn/Co ratios were prepared using polyvinyl pyrrolidone (PVP) as an assistant to control the morphology and exposed crystal faces of composite oxides. The physicochemical properties of the catalysts were systematically characterized and the catalytic activity of NH3-SCR and resistance to SO2/H2O were investigated. It was found that the NO conversion over Mn–Co-0.2-PVP was apparently higher compared with that over Mn–Co-X-PVP (X = 0.9, 0.8, 0.6, and 0.4). This can be interpreted in terms of exposed crystal surface (110) and enhanced adsorption of NH3/NO, and better redox performance resulting from higher Co3+/Co2+ ratio. Furthermore, different PVP and HAc additives have different H2O and SO2 resistance. Mn–Co-0.2-PVP showed good resistance to H2O and SO2 poisoning owing to having more low-temperature (∼200 °C) NO adsorption sites, which are beneficial to promote the de-NOX reaction and less affected by SO2.
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2018
·Vol. 44
·期 5
·3455-3474
·
IF 1.674
Sun Xiao,Guo Rui-tang,Li Ming-yuan,Sun Peng,Pan Wei-guo,Liu Shu-ming,Liu Jian,Liu Shuai-wei
Fe was used as the modifier to improve the performance of CeZr 2 O
x
catalyst for the selective catalytic reduction (SCR) reaction with ammonia. Experimental results revealed that proper Fe species (Fe/Ce molar ratio = 2) could effectively improve the SCR activity of CeZr 2 O
x
, along with the elevated resistance to SO 2 and H 2 O. The characterization results including BET, XRD, H 2 -TPR and NH 3 -TPD confirmed that Fe species in Fe 2 CeZr 2 O
x
catalyst could inhibit the formation of ZrO 2 crystals and lead to higher reducibility and surface acidity. In addition, more Ce 3+ and surface active oxygen species could be detected on Fe 2 CeZr 2 O
x
compared with CeZr 2 O
x
. By means of in situ DRIFT technique, it could be deduced that the SCR reaction process over Fe 2 CeZr 2 O
x
was accelerated mainly through theL–H pathway due to the advanced adsorption of NH 3 and NO
x
species, along with the promoted NO conversion to NO 2 . Therefore, the modification of CeZrO
x
catalyst by Fe had a significant stimulation effect on its low-temperature SCR performance.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2014
·
IF 1.197
Rui-tang Guo,Wen-long Zhen,Wei-guo Pan,Jie-nan Hong,Qiang Jin,Cheng-gang Ding,Shi-yi Guo
CeO2–CuO/Al2O3 catalysts were prepared by three different methods and their activities for selective catalytic reduction (SCR) of NO with NH3 were investigated. As can be seen from the experimental results, the catalyst prepared by the single-step sol–gel (SG) method showed the best SCR activity and resistance to SO2 and H2O. In order to investigate the relationship between the preparation method and the performance of SCR catalysts, the catalysts were characterized by using Brunauer–Emmett–Teller, X-ray diffraction, temperature programmed reduction with hydrogen, temperature programmed desorption with ammonia, X-ray photoelectron spectroscopy, Fourier transform infrared and thermo-gravimetric analysis techniques. It was found that the excellent performance of CeO2–CuO/Al2O3 catalyst prepared by the single-step SG method should be resulted from its large surface area, low crystallinity, high oxygen storage capacity, high NH3 adsorption capacity, high concentration of surface chemisorbed oxygen, weak sulphation process and weak water absorption.
研究领域:
环境科学
·
催化材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Junying Fu,Min Lu,Kejing Fang,Pengmei Lv,Zuhong Xiong
Biodiesel, a renewable liquid fuel, is undergoing eco-transition in catalyst research and development. Calcium oxide (CaO) was a widely studied heterogeneous catalyst due to its considerable activity. However, the poor stability of CaO during storage in air, especially by CO2 and H2O poisoning, presents a challenge. This research successfully developed a high-activity CaO/La2O3 catalyst for biodiesel production with CaO nanoparticles well-dispersed on the La oxide support (Ca/La=0.12). Under mild reaction conditions, a fatty acid methyl esters (FAMEs) yield of 96.9% was achieved. After exposure to air for two weeks, the CaO/La2O3 (Ca/La=0.12) catalyst absorbed 49% less CO2 and 91% less water than pure CaO and keeps 71.4% of the original activity. Thermogravimetric and in-situ Fourier Transform Infrared Spectroscopy analysis reveal that CO2 and H2O will preferentially be captured by La oxides and keep the supported CaO active sites safe. DFT calculations confirmed that CO2 and H2O adsorption on CaO terrace sites became an unfavoured process due to lattice compression of CaO nanoparticles on La2O3, which imparts the CO2/H2O-proof property to CaO/La2O3 catalyst. Methanol adsorption, dissociation, and migration pathways on CaO/La2O3 that produce active methoxy anions at Ca-La interfaces were identified as key steps in achieving efficient catalytic reactions.
研究领域:
化学工程
·
催化材料
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Xiangsen Xu,Jiangxiao Qiao,Shibo Yu,Jiahao Chen,Yiqing Zeng,Feng Zhang,Zhaoxiang Zhong,Weihong Xing
The rational design of catalysts and the establishment of uniform filter structure are key points in the development of high-performance catalytic filters. To resolve the issue of increased N 2 O concentration in catalysts with high vanadium content at high temperatures, a range of catalytic filters with low vanadium loading were fabricated by partially substituting vanadium in 6VWTi catalysts with transition metals (Mn, Cu, Co and Ce). The experimental results show that the introduction of Ce, which leads to rich surface-adsorbed reactive oxygen species, good redox properties and appropriate surface acidity, thus the 1V5CeWTi/SiC catalytic filter exhibits the highest denitration efficiency (NO conversion >90 % at the temperature of 300–500 °C without N 2 O production), presenting significant advantages in contrast to 1VWTi/SiC and 6VWTi/SiC. Furthermore, the preparation technology was optimized to obtain a more uniform structure, which enhanced NH 3 -SCR performance and reduced filter pressure drop. The optimized 1V5CeWTi/SiC also exhibited exceptional resistance to SO 2 + H 2 O and long-term stability for a duration of 200 h at 300 °C, as well as displays a noteworthy efficiency in filtering particulate matter (10 μm SiO 2 ). Therefore, the optimized 1V5CeWTi/SiC catalytic filter holds great potential in the realm of gas purification.
研究领域:
环境工程
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子