A clean and efficient approach for recovery of vanadium and tungsten from spent SCR catalyst

The widespread use of selective catalytic reduction (SCR) catalysts will provide many waste SCR catalysts. These spent catalysts can be identified as hazardous solid waste because they contain a lot of heavy metals. This work aims to develop a clean, green, and economical way to recover valuable metals and regenerate the catalyst. The effect parameters of hydrogen peroxide and ammonium carbonate concentration, time, and temperature on the V and W leaching efficiencies were investigated. The leaching process can be described by a shrinking core model (SCM). The raw material and the residue were characterized by XRD, SEM-EDS, XPS, and Raman analysis. The crystal structure of the leaching residue was stable through the leaching process and can serve as a carrier for the regenerated catalyst. Ammonium paratungstate (APT) and vanadium pentoxide were obtained. This work may introduce a new perspective for the efficient and comprehensive usage of the spent SCR catalyst.

Automated summary

This study aims to develop a clean, green, and economical method for the recovery of valuable metals and regeneration of spent SCR catalysts. The leaching process and mechanism were investigated, and the raw material and residue were characterized by XRD, SEM-EDS, XPS, and Raman analysis to obtain ammonium paratungstate (APT) and vanadium pentoxide. The stable crystal structure of the leaching residue serves as a carrier for the regenerated catalyst, introducing a new perspective for the efficient and comprehensive usage of the spent SCR catalyst.