Influence of MgO Content on Reactivity of Calcined Dolomite with Hydrogen Sulfide

Abstract

The aim of this study is to evaluate H₂S desulfidation reactivity of calcined dolomite. Six dolomites having different CaO/MgO mole ratio were calcined at 1173 K under air atmosphere, and H₂S desulfidation reactivities of them were investigated by a fixed bed reactor.
H2S desulfidation experiments were conducted for 120 minutes at 1173 K under H₂S/N₂ atmosphere. In order to investigate effects of physical and chemical characteristics of calcined dolomites or calcined limestones on its conversions, EDX observation, SEM observation, MgO content in dolomite, BET specific surface area and pore volume were analyzed.
Consequently, it was found that conversions at 120 minutes are closely correlated with the BET specific surface area, and that magnesium oxide content in calcined dolomite have an important role for H₂S desulfidation.
The average H25 absorption capacity per weight of calcined dolomite was 1.17 times of calcined limestone.