MOLECULES
·
2024
·Vol. 29
·期 16
·3747
·
IF 4.2
Guanyu Chen,Weixin Zhang,Rongshu Zhu,Yanpeng Chen,Minghu Zhao,Mei Hong
Zeolite-based catalysts efficiently catalyze the selective catalytic reduction of NOxwith methane (CH4-SCR) for the environmentally friendly removal of nitrogen oxides, but suffer severe deactivation in high-temperature SO2- and H2O-containing flue gas. In this work, SSZ-39 zeolite (AEI topology) with high hydrothermal stability is reported for preparing CH4-SCR catalysts. Mild acid leaching with oxalic acid (OA) not only modulates the Si/Al ratio of commercial SSZ-39 to a suitable value, but also removes some extra-framework Al atoms, introducing a small number of mesopores into the zeolite that alleviate diffusion limitation. Additional Co3O4modification during indium exchange further enhances the catalytic activity of the resulting In-Co3O4/H-SSZ-39(OA). The optimized sample exhibits remarkable performance in CH4-SCR under a gas hourly space velocity (GHSV) of 24,000 h−1and in the presence of 5 vol% H2O. Even under harsh SO2- and H2O-containing high-temperature conditions, it shows satisfactory stability. Catalysts containing Co3O4components demonstrate much higher CH4conversion. The strong mutual interaction between Co3O4and Brønsted acid sites, confirmed by the temperature-programmed desorption of NO (NO-TPD), enables more stable NxOyspecies to be retained in In-Co3O4/H-SSZ-39(OA) to supply further reactions at high temperatures.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
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 Physical Chemistry C
·
2021
·
IF 4.126
Shichao Han,Xiaomin Tang,Ye Ma,Qinming Wu,Jiaqi Shi,Jian Li,Xiangju Meng,Anmin Zheng,Feng-Shou Xiao
The selective catalytic reduction of nitrogen oxide with methane (CH4–SCR) has been considered as an alternative technology for the simultaneous removal of NOx and CH4, and one of the efficient catalysts for this reaction is Co-exchanged SSZ-13 (Co-SSZ-13) zeolite catalyst. However, the preparation of the Co-SSZ-13 zeolite catalyst is costly due to the use of an expensive organic template and Co exchange. We demonstrate here the design of a low-cost cobalt–amine complex (Co–DETA) as a novel structure-directing agent (SDA) for the one-pot synthesis of Co-SSZ-13 zeolite with the assistance of theoretical calculations. Physicochemical characterizations including X-ray diffraction, scanning electron microscopy, N2 sorption, and magic-angle spinning nuclear magnetic resonance show that the Co-SSZ-13 zeolite has good crystallinity, a cubic morphology, a high surface area, and four-coordinated aluminum species. Furthermore, thermogravimetry–differential thermal analysis, Fourier transform infrared spectroscopy, and diffuse reflectance ultraviolet–visible spectroscopy confirm that the Co–DETA complex acts as a SDA for the synthesis of Co-SSZ-13 zeolite. More importantly, the Co-SSZ-13 zeolite exhibits good catalytic performance in the CH4–SCR reaction with 10% H2O in the feed gas stream. The efficient and facile synthesis of Co-SSZ-13 zeolite plus its good catalytic performance might offer a good opportunity for its industrial applications in the future.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2023
·
IF 3.7
Jiuhu Zhao,Huiying Li,Yungang Wang,Rongshu Zhu,Senlin Sun,Jingwen Zhang,Chaolin Li,Mei Hong
Mesoporous In/Hβ-X series catalysts were prepared by desilication method with tetrapropylammonium hydroxide (TPAOH) and indium incorporation for selective catalytic reduction of NO with methane (CH 4 -SCR). The post desilication treatment conditions for preparing In/Hβ-X were optimized. Etching time is the most important desilication parameter influencing the resulting CH 4 -SCR performance of the catalyst. The In/Hβ-3 sample which was etched for 3 h presents the highest NO x conversion, 22% higher than In/H-Beta counterparts using commercial microporous beta. Obvious analysis reveals that besides generating mesopores, controlled desilication can modulate the proportion of InO + active sites and surface oxygen species, allowing more active sites to be exposed.
研究领域:
催化
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 13
·2691
·
IF 4.6
Jiuhu Zhao,Jingjing Jiang,Guanyu Chen,Meng Wang,Xiaoyuan Zuo,Yanjiao Bi,Rongshu Zhu
The selective catalytic reduction of NOxwith CH4(CH4-SCR) holds the potential to simultaneously abate harmful NOxand CH4greenhouse gases. In this study, a series of bimetallic M-In/H-SSZ-39 catalysts (where M represents Cr, Co, Ce, and Fe) were prepared via an ion exchange method and subsequently evaluated for their CH4-SCR activity. The influences of the preparation parameters, including the metal ion concentration and calcination temperature, as well as the operating conditions, such as the CH4/NO ratio, O2concentration, water vapor content, and gas hourly space velocity (GHSV), on the catalytic activity of the optimal Cr-In/H-SSZ-39 catalyst were meticulously examined. The results revealed that the Cr-In/H-SSZ-39 catalyst exhibited peak CH4-SCR catalytic performance when the Cr(NO3)3concentration was 0.0075 M, the In(NO3)3concentration was 0.066 M, and the calcination temperature was 500 °C. Under optimal operating conditions, namely GHSV of 10,000 h−1, 400 ppm NO, 800 ppm CH4, 15 vol% O2, and 6 vol% H2O, the NOxconversion rate reached 93.4%. To shed light on the excellent performance of Cr-In/H-SSZ-39 under humid conditions, a comparative analysis of the crystalline phase, chemical composition, pore structure, surface chemical state, surface acidity, and redox properties of Cr-In/H-SSZ-39 and In/H-SSZ-39 was conducted. The characterization results indicated that the incorporation of Cr into In/H-SSZ-39 enhanced its acidity and also facilitated the generation of InO+active species, which promoted the oxidation of NO and the activation of CH4, respectively. A synergistic effect was observed between Cr and In species, which significantly improved the redox properties of the catalyst. Consequently, the activated CH4could further interact with InO+to produce carbon-containing intermediates such as HCOO−, which ultimately reacted with nitrate-based intermediates to yield N2, CO2, and H2O.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）