@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"
}