Experimental study on the selective catalytic reduction of NO by C<sub>3</sub>H<sub>6</sub> over Cu modified Fe/Al-PILC catalysts

CHENG Jiang-hao; SU Ya-xin; LIN Rui; ZHANG Xian-wei; WEN Ni-ni; DENG Wen-yi; ZHOU Hao

Volume 47 Issue 7

Jul. 2019

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Article Navigation > Journal of Fuel Chemistry and Technology > 2019 > 47(7): 823-833

CHENG Jiang-hao, SU Ya-xin, LIN Rui, ZHANG Xian-wei, WEN Ni-ni, DENG Wen-yi, ZHOU Hao. Experimental study on the selective catalytic reduction of NO by C3H6 over Cu modified Fe/Al-PILC catalysts[J]. Journal of Fuel Chemistry and Technology, 2019, 47(7): 823-833.

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CHENG Jiang-hao, SU Ya-xin, LIN Rui, ZHANG Xian-wei, WEN Ni-ni, DENG Wen-yi, ZHOU Hao. Experimental study on the selective catalytic reduction of NO by C₃H₆ over Cu modified Fe/Al-PILC catalysts[J]. Journal of Fuel Chemistry and Technology, 2019, 47(7): 823-833.

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Experimental study on the selective catalytic reduction of NO by C₃H₆ over Cu modified Fe/Al-PILC catalysts

1.
School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
2.
Changzhou Vocational Institute of Engineering, Changzhou 213164, China

Funds:

Jiangsu Province Natural Science Foundation BK20181161

the Fundamental Research Funds for the Central Universities 2232019D3-24

National Natural Science Foundation of China 51278095

More Information

Corresponding author: SU Ya-xin, Tel: 021-67792552, E-mail: suyx@dhu.edu.cn
Received Date: 2019-03-28
Rev Recd Date: 2019-05-10

Available Online: 2021-01-23

Publish Date: 2019-07-10

Abstract

Abstract

In order to improve the low temperature activity of Fe/Al-PILC catalysts for SCR of NO, copper doping was used for the modification. xCu-Fe/Al-PILC catalysts were prepared by ultrasonic impregnation technique and characterized by XRD, N₂ adsorption-desorption, H₂-TPR, UV-vis, XPS and Py-FTIR. The SCR of NO with C₃H₆ tests were carried out in a fixed bed reactor. The experimental results showed that the xCu-Fe/Al-PILC catalysts can effectively solve the problem of insufficient SCR activity of Fe/Al-PILC catalysts at low temperature and as well as improve the activity at medium and high temperature. High NO reduction efficiency, 80% and beyond could be achieved at a wide temperature range of 200-500℃ by the catalysts, among which 0.13Cu-Fe/Al-PILC exhibited 90% of the NO conversion at 250-500℃ and maximum NO reduction efficiency of 93% at 250℃. XRD and N₂ adsorption-desorption results proved that the catalysts modified by copper provided more active sites and increased the reaction rate. The results of H₂-TPR indicated that the doping of copper improved the catalyst's redox ability at lower temperature, while enhanced the catalyst's redox ability at medium and high temperature. UV-vis and XPS study showed that the doping of copper not only increased the higher oxidation state of iron but also produced more isolated Fe³⁺ which is the low-temperature active species. Py-FTIR test illustrated that Lewis acid and Brönsted acid existed simultaneously on the catalyst surface, and Lewis acid sites were the activity center of the SCR reaction.
- NO reduction,
- SCR-C₃H₆,
- xCu-Fe/Al-PILC,
- low-temperature activity

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References(58)

References

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