Comparative Study of SO2 and SO2/SO3 Poisoning and Regeneration of Cu/BEA and Cu/SSZ-13 for NH3 SCR
Artikel i vetenskaplig tidskrift, 2021

Two copper-exchanged zeolites, Cu/SSZ-13 and Cu/BEA, were studied as catalysts for the selective reduction of NOx by NH3 (NH3-SCR). Their activities for standard SCR (NOx = NO) and fast SCR (NOx = 50% NO + 50% NO2) were measured before and after sulfur poisoning at 250 °C. The effect of 30 ppm SO2 and a mixture of 24 ppm SO3 + 6 ppm SO2 was evaluated. The repetition of subsequent activity measurements served as regeneration method in SCR conditions. SO2 deactivated Cu/SSZ-13 whereas Cu/BEA was only moderately affected. SO3 led to stronger deactivation of both catalysts than SO2. However, also for this case, the Cu/BEA was significantly less affected than Cu/SSZ-13, even though Cu/BEA contained larger amount of stored sulfur. One possible reason for this could be the large pores of Cu/BEA, where the sulfur species possibly resulted in less sterical hindrance than in the small pore SSZ-13 structure. NH3 temperature-programmed desorption (NH3-TPD) showed no loss of storage sites upon sulfur treatment and subsequent regeneration. Partial activity recovery was observed after a period in SCR conditions at 400 °C and 500 °C. Temperature at 300 °C was insufficient to regenerate the catalysts. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of NO adsorption suggested that SO2 interacts with the ZCuOH sites on Cu/SSZ-13, causing the strong poisoning.

Cu/zeolites

Poisoning

NH SCR 3

SO and SO 2 3

Författare

Xavier Auvray

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

Maria Arvanitidou

Student vid Chalmers

Åsa Högström

Student vid Chalmers

Jonas Jansson

Volvo Group

Sheedeh Fouladvand

Volvo Group

Louise Olsson

Chalmers, Kemi och kemiteknik, Kemiteknik

Emission Control Science and Technology

21993629 (ISSN) 21993637 (eISSN)

Vol. In Press

Ämneskategorier

Oorganisk kemi

Annan kemiteknik

Annan kemi

DOI

10.1007/s40825-021-00203-4

Mer information

Senast uppdaterat

2021-11-01