Deactivation mechanism of Cu active sites in Cu/SSZ-13 — Phosphorus poisoning and the effect of hydrothermal aging
Artikel i vetenskaplig tidskrift, 2020

Non-poisoned and P-poisoned Cu/SSZ-13 catalysts with different types of Cu sites, i.e., [Cu(OH)]+ and Cu2+, were investigated for NH3-SCR. Phosphorus was found to interact more with [Cu(OH)]+ than Cu2+. Moreover, less phosphorus was required per Cu for poisoning in the samples with a high content of [Cu(OH)]+. We propose a phosphorus poisoning mechanism based on H2-TPR and XPS: poisoning of one Cu2+ involved two P atoms, i.e., P2O5, but for [Cu(OH)]+ contamination, only one P atom (PO3− or PO43−) is needed. Furthermore, phosphorus poisoning resulted in a decline in NH3/NO oxidation and an improvement in SCR activity at high temperatures. Upon hydrothermal aging, [Cu(OH)]+−phosphate/metaphosphate complexes were likely easier detached from the framework than the Cu2+−P2O5 species. This resulted in that the P-poisoned catalyst with high content [Cu(OH)]+ experienced more severe deactivation and dealumination than the non-poisoned catalyst. Additionally, 27Al-NMR suggested that the formation of AlPO4 has a linear relationship with [Cu(OH)]+/Cu2+ ratios.

Cu/SSZ-13

Hydrothermal aging

Zeolite

SCR

Phosphorus-poisoned

Författare

Aiyong Wang

Chalmers, Kemi och kemiteknik, Kemiteknik, Kemisk apparat- och reaktionsteknik

Kunpeng Xie

Chalmers, Kemi och kemiteknik, Kemiteknik, Kemisk apparat- och reaktionsteknik

Diana Bernin

Chalmers, Kemi och kemiteknik, Kemiteknik, Kemisk apparat- och reaktionsteknik

A. Kumar

Cummins Inc.

K. Kamasamudram

Cummins Inc.

Louise Olsson

Chalmers, Kemi och kemiteknik, Kemiteknik

Applied Catalysis B: Environmental

0926-3373 (ISSN) 1873-3883 (eISSN)

Vol. 269 118781

Ämneskategorier

Oorganisk kemi

Kemiteknik

Organisk kemi

Drivkrafter

Hållbar utveckling

Styrkeområden

Transport

Fundament

Grundläggande vetenskaper

DOI

10.1016/j.apcatb.2020.118781

Mer information

Senast uppdaterat

2021-02-08