Ultrasound intensified production of titanium phosphate from mine waste streams

Purpose and goal:

Leaching concentrates of titanium carrying minerals, as part of the mine tailing streams from LKAB to produce titanium phosphate, TiP1. Develop a beneficiation process for the mine tailings by desliming, silicate flotation and gravimetric separation and high titanium recovery, produce a titanium rich concentrate. Develop a leaching procedure by acoustic cavitation using 30% sulfuric acid to generate titanyl sulfate from the concentrate.

Evaluate a procedure for filtering and concentrating the leachate by phosphoric acid to get a sufficient concentration for synthesis of TiP1. Expected results and effects:

Defined the mineral composition of the mine tailings, characterized variations, and identified the most suitable tailings. Defined and tested a process aiming for the generation of an enriched concentrate of titanium rich minerals Evaluated parameters critical for energy efficient leaching and yield, defined the need for redox potential control

Evaluated ultrasonic leaching efficiency regarding excitation frequencies and signal time characteristics Validated the synthesis of TiP1 from filtrated leachate containing TiOSO4(aq) according to patented protocol Approach and implementation:

Silicate flotation and shaking table tests were carried out to potentially upgrade titanite and other Ti-bearing minerals like ilmenite and rutile. Characterization of the processes’ products was done by the mean of XRF and QEMSCAN at LKAB, Malmberget. Ultrasound intensified and traditional leching procedures were compared with respect to generate titanyl sulfate from a titanium rich concentrate using sulfuric acid at 60 degrees.

The synthesis procedure of titanium phosphate from the filtered leachate was validated by using a pre-fabricated concentrate of titanyl sulfate.