Experimental and thermodynamic study on SO2 reduction to elemental sulfur by activated coke and pyrolysis gas: Influence of the reaction atmosphere.

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 SO 2 reduction by CO and H 2. The reactivity of CO reducing SO 2 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 CO 2 on SO 2 reduction was slight, while the participation of H 2 O 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 SO 2 , CO 2 or H 2 O. • The coupling reduction of SO 2 with active coke and pyrolysis gas is effective. • Activated coke is used as both reducing agent and catalyst in the SO 2 reduction. • Reduction of SO 2 by CO and H 2 in activated coke bed is almost mutually independent. • CO 2 affects SO 2 reduction to elemental sulfur to a small degree. • The presence of H 2 O had a significant negative effect on the SO 2 reduction. [ABSTRACT FROM AUTHOR]