STUDY OF LOW-TITANIUM SLAG AND SODA BAKING PROCESS

Abstract

The article presents study results of soda and low-titanium slag baking, where the slag is produced during processing of titanium magnetite concentrate. The purpose of baking is to change the mineralogical composition of Ti-containing phases and obtain a product suitable for chemical separation of titanium dioxide from impurities. The X-ray phase analysis revealed that the obtained titanium slag belonged to the spinel-anosovit type. The article studies the factors influencing the baking process: the slag to soda mass ratio, the process duration, the temperature and the size of slag particles. The thermal analysis of the slag and soda baking process revealed that the optimum process temperature was 900°C. This temperature ensured formation of sodium titanates and a cake of sufficient porosity. The article demonstrates that effective decomposition pro cess requires a pretreatment of titanium slag by fine grinding. It was found that grinding of titanium slag particles to 40 μm contributes to more complete decomposition of the anosovite and formation of sodium titanates. It was found that during titanium slag and soda baking at the slag to soda mass ratio of 1 : 1,05, decomposition of anosovite occurred, and virtually all titanium was bound to sodium titanates. Optimal process conditions were determined as follows: slag to soda mass ratio – 1 : 1,05, baking temperature – 900 ° C, duration – 60 minutes and slag particle size – 40 μm. During baking, the titanium-containing slag phases were converted into Na 2 TiO 3 and Na 8 Ti 5 O 14 . The presence of a significant amount of silicon dioxide and the sodium-magnesium silicate phase was observed in the cake. The electron microprobe analysis of the cake showed that impurity elements were adsorbed on the particles of formed Na 2 TiO 3 .