Synthetic rutile enhancement process

SREP [Synthetic Rutile Enhancement Process] An improved version of the Becher process for upgrading titanium ores. It is designed to reduce the level of radioactive contamination in the product. Developed in the early 1990s by Renison Goldfields, Australia, in collaboration with the CSIRO, Perth, and first operated in Narngulu in 1996. 

An important modification of the Becher process is the development of the Synthetic Rutile Enhancement Process (SREP) route, using various leaching methods to reduce the level of radioactivity in the synthetic rutile product to internationally acceptable levels. 

In a process variant (Enhanced Acid Regeneration System EARS process), the ilmenite is roasted to convert the titanium component into the insoluble rutile form and to condition the iron component for leaching. The product is then rapidly leached at atmospheric pressure in hydrochloric acid to remove the iron, leaving rutile crystals in the former ilmenite grain. This synthetic rutile (typically 96-98% Ti02) is then washed, filtered, and calcined. The iron chloride leach liquors are processed to regenerate the acid, and the iron oxide pellets can be sold for use by the steel or cement industries. 

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