Experimental research and kinetics analysis on hydrogen reduction of limonite

Abstract

This article presents experimental studies on the effects of H2 on the reduction degree and rate of limonite at different temperatures and kinetic analysis during the hydrogen reduction. The water loss of limonite was investigated by thermal gravimetric analysis. Limonite of 8 to 12 mm in granularity was reduced with 4 L·min-1 H2 at five temperatures of 750 to 950℃. As the reduction reaction proceeded, the reduction degree increased, and the sequence of 5 reduction degree curves was consistent with that of reaction temperature when t>28 min. The apparent activation energy was kinetically calculated to be 15.323 kJ·mol-1, so diffusion is the restrictive step of the reduction reaction.

Keywords

• ironmaking
• limonite
• hydrogen reduction
• reduction kinetics
• thermal gravimetric analysis