This study examined the activity of Cu-Sn-Zr-based catalysts for the direct sulfur recovery process under the regeneration gas containing oxygen, which consisted of sulfur dioxide and nitrogen as the main components. The catalytic reaction behavior was investigated with the addition of a copper promoter, and the reactive temperature for SO2 reduction was investigated according to the change in temperature by increasing and decreasing the temperature in the processes in stages. The catalytic reaction pathway changed with the catalysis of the promoter, and the activity of the reacted catalyst was higher than that of the fresh catalyst due to the sulfidation of the Cu-promoter. CuS leads to a COS intermediate mechanism, and prevents the deactivation of Cu-Sn-Zr-based by oxygen contained in the regeneration gas. (C) 2015 Elsevier B.V. All rights reserved.