Regeneration of water-deactivated Cu/SAPO-34(MO) with acids
Journal article, 2020

The Cu/SAPO-34 catalysts, used for NH3 selective catalytic reduction (SCR), are systemically studied with various characterization techniques before and after low temperature water deactivation and regeneration using techniques such as XRD, BET, ICP-SFMS, 27Al MAS NMR, 29Si MAS NMR, and H2-TPR. Analysis of results suggests that, during low-temperature water deactivation, hydrolysis of Si-O-Al occurs resulting in Si condensation and formation of Si clusters. It is proposed that these formed Si clusters are mainly responsible for the deactivation of Cu/SAPO-34 catalysts since they suppress the mobility of [Cu-(NH3)]+ and hinder the formation of the transient [CuI(NH3)2]+-O2-[CuI(NH3)2]+ intermediate, which is considered to be the rate-limiting step for NH3-SCR reaction. The regeneration of the deactivated Cu/SAPO-34 catalysts with acid can be explained by the ability of the acid to convert the Si clusters back to Si-O-H, which is able to revert to the SAPO-34 framework via reverse hydrolysis as the temperature increases.

Author

Jung Won Woo

Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Engineering Design

Competence Centre for Catalysis (KCK)

Diana Bernin

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Engineering Design

Homayoun Ahari

FCA US LLC

Mark Shost

FCA US LLC

Michael Zammit

FCA US LLC

Louise Olsson

Chalmers, Chemistry and Chemical Engineering, Chemical Technology

Competence Centre for Catalysis (KCK)

Catalysis Science and Technology

2044-4753 (ISSN) 2044-4761 (eISSN)

Vol. 10 5 1539-1550

Subject Categories

Chemical Process Engineering

Other Chemical Engineering

Organic Chemistry

DOI

10.1039/c9cy02031d

More information

Latest update

4/30/2020