To develop a new process of sulfur recovery for activated coke desulfurization, reduction of sulfur dioxide by activated coke and pyrolysis gas from powder coke fast preparation system was studied experimentally and theoretically. The distribution of gas products in the experiment was measured by GC-MS analyzer and refinery gas analyzer, while the thermodynamic equilibrium data was calculated by the Factsage software. The activated coke presented great catalytic performance for SO2 reduction by CO and H-2. The reactivity of CO reducing SO2 was higher than that of H-2, and the two gaseous reducing agents were independent of each other during the reaction process. The effect of CO2 on SO2 reduction was slight, while the participation of H2O resulted in a significant decrease in S yield. The unsteady state experiment shows that the catalytic ability of activated coke did not affect by reaction between carbon and SO2, CO2 or H2O. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.