High temperature corrosion tests were performed in a fluidized bed of black Kraff liquor using a pulsed burner process to determine the optimum materials for use in a commercial application. The materials tested included three different austenific stainless steels, Type 446 martensitic stainless steel, a high temperature carbon steel, 153MA, and four nickel base alloys. All materials performed well with no corrosion attributed to the environment created by the decomposition of a black Kraft liquor. This behavior was cantrary ta what was expected due ta the high concentration of H2S present in the high temperature, 562°C, atmosphere.