Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR
Manganese oxides (MnO<i><sub>x</sub></i>) have attracted particular attention in the selective catalytic reduction of NO<i><sub>x</sub></i> with NH<sub>3</sub> (NH<sub>3</sub>-SCR) because of their excellent low-temperature acti...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Catalysts |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4344/12/10/1291 |
| _version_ | 1797474384712040448 |
|---|---|
| author | Yuanyuan Dong Baofang Jin Shaomian Liu Jiajian Gao Kangjun Wang Fabing Su |
| author_facet | Yuanyuan Dong Baofang Jin Shaomian Liu Jiajian Gao Kangjun Wang Fabing Su |
| author_sort | Yuanyuan Dong |
| collection | DOAJ |
| description | Manganese oxides (MnO<i><sub>x</sub></i>) have attracted particular attention in the selective catalytic reduction of NO<i><sub>x</sub></i> with NH<sub>3</sub> (NH<sub>3</sub>-SCR) because of their excellent low-temperature activity. Herein, we prepared a highly efficient MnO<sub>2</sub> (MnO<sub>2</sub>-M) catalyst through a facile ball milling-assisted redox strategy. MnO<sub>2</sub>-M shows a 90% NO<i><sub>x</sub></i> conversion in a wide operating temperature window of 75–200 °C under a gas hourly space velocity of 40,000 h<sup>−1</sup>, which is much more active than the MnO<sub>2</sub> catalyst prepared by the redox method without the ball-milling process. Moreover, MnO<sub>2</sub>-M exhibits better H<sub>2</sub>O and SO<sub>2</sub> resistance. The enhanced catalytic properties of MnO<sub>2</sub>-M originated from the high surface area, abundant oxygen vacancies, more acid sites, and higher Mn<sup>4+</sup> content induced by the ball-milling process. In situ DRIFTS studies probed the reaction intermediates, and the SCR reaction was deduced to proceed via the typical Eley–Rideal mechanism. This work provides a facile method to enhance the catalytic performance of Mn-based catalysts for low-temperature denitrification and deep insights into the NH<sub>3</sub>-SCR reaction process. |
| first_indexed | 2024-03-09T20:29:18Z |
| format | Article |
| id | doaj.art-8ea0f08579d941929b25153ceedc1d85 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-09T20:29:18Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-8ea0f08579d941929b25153ceedc1d852023-11-23T23:26:53ZengMDPI AGCatalysts2073-43442022-10-011210129110.3390/catal12101291Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCRYuanyuan Dong0Baofang Jin1Shaomian Liu2Jiajian Gao3Kangjun Wang4Fabing Su5Key Laboratory of Resources Chemicals and Materials, Shenyang University of Chemical Technology, Ministry of Education, Shenyang 110142, ChinaState Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, ChinaState Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, ChinaInstitute of Sustainability for Chemicals, Energy and Environment, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, SingaporeKey Laboratory of Resources Chemicals and Materials, Shenyang University of Chemical Technology, Ministry of Education, Shenyang 110142, ChinaState Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, ChinaManganese oxides (MnO<i><sub>x</sub></i>) have attracted particular attention in the selective catalytic reduction of NO<i><sub>x</sub></i> with NH<sub>3</sub> (NH<sub>3</sub>-SCR) because of their excellent low-temperature activity. Herein, we prepared a highly efficient MnO<sub>2</sub> (MnO<sub>2</sub>-M) catalyst through a facile ball milling-assisted redox strategy. MnO<sub>2</sub>-M shows a 90% NO<i><sub>x</sub></i> conversion in a wide operating temperature window of 75–200 °C under a gas hourly space velocity of 40,000 h<sup>−1</sup>, which is much more active than the MnO<sub>2</sub> catalyst prepared by the redox method without the ball-milling process. Moreover, MnO<sub>2</sub>-M exhibits better H<sub>2</sub>O and SO<sub>2</sub> resistance. The enhanced catalytic properties of MnO<sub>2</sub>-M originated from the high surface area, abundant oxygen vacancies, more acid sites, and higher Mn<sup>4+</sup> content induced by the ball-milling process. In situ DRIFTS studies probed the reaction intermediates, and the SCR reaction was deduced to proceed via the typical Eley–Rideal mechanism. This work provides a facile method to enhance the catalytic performance of Mn-based catalysts for low-temperature denitrification and deep insights into the NH<sub>3</sub>-SCR reaction process.https://www.mdpi.com/2073-4344/12/10/1291MnO<sub>2</sub>ball-millinghigh surface areaoxygen vacancieslow-temperature NH<sub>3</sub>-SCR |
| spellingShingle | Yuanyuan Dong Baofang Jin Shaomian Liu Jiajian Gao Kangjun Wang Fabing Su Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR Catalysts MnO<sub>2</sub> ball-milling high surface area oxygen vacancies low-temperature NH<sub>3</sub>-SCR |
| title | Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR |
| title_full | Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR |
| title_fullStr | Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR |
| title_full_unstemmed | Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR |
| title_short | Abundant Oxygen Vacancies Induced by the Mechanochemical Process Boost the Low-Temperature Catalytic Performance of MnO<sub>2</sub> in NH<sub>3</sub>-SCR |
| title_sort | abundant oxygen vacancies induced by the mechanochemical process boost the low temperature catalytic performance of mno sub 2 sub in nh sub 3 sub scr |
| topic | MnO<sub>2</sub> ball-milling high surface area oxygen vacancies low-temperature NH<sub>3</sub>-SCR |
| url | https://www.mdpi.com/2073-4344/12/10/1291 |
| work_keys_str_mv | AT yuanyuandong abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr AT baofangjin abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr AT shaomianliu abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr AT jiajiangao abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr AT kangjunwang abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr AT fabingsu abundantoxygenvacanciesinducedbythemechanochemicalprocessboostthelowtemperaturecatalyticperformanceofmnosub2subinnhsub3subscr |