Reduction of Norwegian and Indian ilmenite with carbon monoxide and hydrogen gas blends

Abstract

Synthesis gas, produced from natural gas, can be used to minimise coal consumption and carbon dioxide emissions during the processing of ilmenite. Two different ilmenite ores have been reduced with carbon monoxide and hydrogen mixtures to investigate the effects of temperature and gas composition on the final product. Thermogravimetric analysis was used to observe the reaction progress. Experimental work revealed that between 900 and 1000 °C the hydrogen content in the gas has an equally significant effect as the temperature. Statistical analysis determined that the source of the ore did not have a significant effect on the reaction rate. Armalcolite is one of the main products of pre-reduction in addition to metallic iron and rutile from these ilmenite concentrates. There is also some indication that titanium dioxide is reduced. Optical microscope images revealed that increasing amounts of hydrogen resulted in smaller more uniformly distributed metallic iron particles.