TY  - JOUR
AU  - Wan, Yuyi
AU  - Yang, Guangpeng
AU  - Xiang, Jinyao
AU  - Shen, Xiaoqiang
AU  - Yang, Dafei
AU  - Chen, Yanrong
AU  - Rac, Vladislav
AU  - Rakić, Vesna
AU  - Du, Xuesen
PY  - 2020
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5328
AB  - Cu-SAPO-34 catalysts with varied Cu loadings were synthesized through ion exchange to study the influence of water on the NH3-SCR reaction. The catalytic activities were evaluated by selective catalytic reduction of NO under a reactant feed in the presence/absence of water. Transient experiments were designed to study the response of NO conversion to the presence of water. H-2-TPR and DFT calculations were performed to study the reducibility of Cu species. NH3-TPD and XPS were conducted to reveal the migration of Cu species. The results show that water could remarkably improve NO reduction activities and the promoting effect is more significant on the catalyst with low Cu loading. Both transient and permanent influences were found in this promoting phenomenon. For the transient influence, water has been proved to accelerate the re-oxidation half-cycle. Moreover, water can enhance the promoting effect of the SCR feed on the migration of Cu species. These unanchored Cu ions migrate to defect sites to form active sites, which lead to a permanent influence of water.
PB  - Royal Soc Chemistry, Cambridge
T2  - Dalton Transactions
T1  - Promoting effects of water on the NH3-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species
EP  - 773
IS  - 3
SP  - 764
VL  - 49
DO  - 10.1039/c9dt03848e
ER  - 

@article{
author = "Wan, Yuyi and Yang, Guangpeng and Xiang, Jinyao and Shen, Xiaoqiang and Yang, Dafei and Chen, Yanrong and Rac, Vladislav and Rakić, Vesna and Du, Xuesen",
year = "2020",
abstract = "Cu-SAPO-34 catalysts with varied Cu loadings were synthesized through ion exchange to study the influence of water on the NH3-SCR reaction. The catalytic activities were evaluated by selective catalytic reduction of NO under a reactant feed in the presence/absence of water. Transient experiments were designed to study the response of NO conversion to the presence of water. H-2-TPR and DFT calculations were performed to study the reducibility of Cu species. NH3-TPD and XPS were conducted to reveal the migration of Cu species. The results show that water could remarkably improve NO reduction activities and the promoting effect is more significant on the catalyst with low Cu loading. Both transient and permanent influences were found in this promoting phenomenon. For the transient influence, water has been proved to accelerate the re-oxidation half-cycle. Moreover, water can enhance the promoting effect of the SCR feed on the migration of Cu species. These unanchored Cu ions migrate to defect sites to form active sites, which lead to a permanent influence of water.",
publisher = "Royal Soc Chemistry, Cambridge",
journal = "Dalton Transactions",
title = "Promoting effects of water on the NH3-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species",
pages = "773-764",
number = "3",
volume = "49",
doi = "10.1039/c9dt03848e"
}

Wan, Y., Yang, G., Xiang, J., Shen, X., Yang, D., Chen, Y., Rac, V., Rakić, V.,& Du, X.. (2020). Promoting effects of water on the NH3-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species. in Dalton Transactions
Royal Soc Chemistry, Cambridge., 49(3), 764-773.
https://doi.org/10.1039/c9dt03848e

Wan Y, Yang G, Xiang J, Shen X, Yang D, Chen Y, Rac V, Rakić V, Du X. Promoting effects of water on the NH3-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species. in Dalton Transactions. 2020;49(3):764-773.
doi:10.1039/c9dt03848e .

Wan, Yuyi, Yang, Guangpeng, Xiang, Jinyao, Shen, Xiaoqiang, Yang, Dafei, Chen, Yanrong, Rac, Vladislav, Rakić, Vesna, Du, Xuesen, "Promoting effects of water on the NH3-SCR reaction over Cu-SAPO-34 catalysts: transient and permanent influences on Cu species" in Dalton Transactions, 49, no. 3 (2020):764-773,
https://doi.org/10.1039/c9dt03848e . .

TY  - JOUR
AU  - Yang, Guangpeng
AU  - Du, Xuesen
AU  - Ran, Jingyu
AU  - Wang, Xiangmin
AU  - Chen, Yanrong
AU  - Zhang, Li
AU  - Rac, Vladislav
AU  - Rakić, Vesna
AU  - Crittenden, John
PY  - 2020
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5346
AB  - SCR activity of Cu-SAPO-34 catalyst was reduced by alkali metal ions. The alkali metals ions (Li+, Na+ and K+) have shown irregular influences on Cu-SAPO-34. The order of poisoning strengths under 400 degrees C was found to be: Na+ > K+ Li+, which is not consistent with the basicities of their corresponding metals. Experimental results and calculations showed that the alkali metal ions readily replace H+ and Cu2+/Cu3+ ions. These exchanges result in the loss of Bronsted acid sites and migration of isolated Cu2+ ions in Cu-SAPO-34, which decrease the NH3-SCR activity. Both the basicity and ion diameter will affect the exchanging behavior of an alkali ion. Na+ and Li+ ions will influence both H+ and Cu2+/Cu+ ions but K+ ions only preferably replace the H+ We hypothesize that K+ cannot enter into a small ring (6-membered ring) to replace a Cu2+/Cu+ ion because of its large ion diameter. The displaced Cu2+/Cu+ ions will transfer to adjacent unbonded Al site to form a CuAlO2 species.
PB  - Elsevier, Amsterdam
T2  - Journal of Hazardous Materials
T1  - Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NOx with ammonia
VL  - 387
DO  - 10.1016/j.jhazmat.2019.122007
ER  - 

@article{
author = "Yang, Guangpeng and Du, Xuesen and Ran, Jingyu and Wang, Xiangmin and Chen, Yanrong and Zhang, Li and Rac, Vladislav and Rakić, Vesna and Crittenden, John",
year = "2020",
abstract = "SCR activity of Cu-SAPO-34 catalyst was reduced by alkali metal ions. The alkali metals ions (Li+, Na+ and K+) have shown irregular influences on Cu-SAPO-34. The order of poisoning strengths under 400 degrees C was found to be: Na+ > K+ Li+, which is not consistent with the basicities of their corresponding metals. Experimental results and calculations showed that the alkali metal ions readily replace H+ and Cu2+/Cu3+ ions. These exchanges result in the loss of Bronsted acid sites and migration of isolated Cu2+ ions in Cu-SAPO-34, which decrease the NH3-SCR activity. Both the basicity and ion diameter will affect the exchanging behavior of an alkali ion. Na+ and Li+ ions will influence both H+ and Cu2+/Cu+ ions but K+ ions only preferably replace the H+ We hypothesize that K+ cannot enter into a small ring (6-membered ring) to replace a Cu2+/Cu+ ion because of its large ion diameter. The displaced Cu2+/Cu+ ions will transfer to adjacent unbonded Al site to form a CuAlO2 species.",
publisher = "Elsevier, Amsterdam",
journal = "Journal of Hazardous Materials",
title = "Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NOx with ammonia",
volume = "387",
doi = "10.1016/j.jhazmat.2019.122007"
}

Yang, G., Du, X., Ran, J., Wang, X., Chen, Y., Zhang, L., Rac, V., Rakić, V.,& Crittenden, J.. (2020). Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NOx with ammonia. in Journal of Hazardous Materials
Elsevier, Amsterdam., 387.
https://doi.org/10.1016/j.jhazmat.2019.122007

Yang G, Du X, Ran J, Wang X, Chen Y, Zhang L, Rac V, Rakić V, Crittenden J. Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NOx with ammonia. in Journal of Hazardous Materials. 2020;387.
doi:10.1016/j.jhazmat.2019.122007 .

Yang, Guangpeng, Du, Xuesen, Ran, Jingyu, Wang, Xiangmin, Chen, Yanrong, Zhang, Li, Rac, Vladislav, Rakić, Vesna, Crittenden, John, "Irregular influence of alkali metals on Cu-SAPO-34 catalyst for selective catalytic reduction of NOx with ammonia" in Journal of Hazardous Materials, 387 (2020),
https://doi.org/10.1016/j.jhazmat.2019.122007 . .