Exceptional High-Purity TiO2 Product Achieved

Empire Metals Limited, the AIM-quoted and OTCQB-traded resource exploration and development company, is pleased to announce the results from its most recent titanium dioxide ("TiO2") product development testwork programme, carried out on mineral flotation concentrates produced from the in-situ mineralised weathered cap that extends across the giant Pitfield Project ('Pitfield'), located in Western Australia.

Highlights

• A very high-purity TiO2 product, assaying at 99.25% TiO2 has been achieved through conventional beneficiation, leaching and refining processes.
• The TiO2 product contains non-detectable, or extremely low levels of deleterious impurities and is expected to be suitable for high-quality titanium sponge metal or high-grade titanium dioxide pigment production.
• Bulk samples collected from the weathered cap (announced 17 February 2025) have been delivered to the metallurgical laboratory and these will be utilised to produce multiple, finished product samples for marketing purposes.

Shaun Bunn, Managing Director, said: "We have achieved an extraordinary outcome from our most recent product development testwork, which has delivered an exceptional high-grade, high-purity TiO2 product that should be ideal for either titanium sponge metal or high-quality TiO2 pigment production.

"It is remarkable that our technical team has so rapidly produced a high-purity TiO₂ product. We believe this not only highlights the effectiveness of our processing approach but also underscores the potential value of our product. Metallurgical testing and process optimisation continues, and with the availability of the 70 tonnes of bulk sample collected in February we will now be able to significantly scale up the testwork and produce a variety of final product samples to share with prospective downstream end-users."

Product Development Testwork

An acid bake-water leach process using sulphuric acid was applied, with parameters similar to that tested during the initial product development test programme (announced 10 March 2025). The TiO2 product purification and product finishing stages were tested at ALS Metallurgy laboratories, located in Perth, Western Australia. All assays were conducted at ALS Metallurgy by their in-house metallurgy-specific assay lab.

The most recent product development metallurgical test work was undertaken on flotation concentrates recovered from the near surface, highly weathered in-situ saprolitic zone. Diamond drill core collected from two holes, DD24TOM004 and DD24TOM005, formed the feed composite (refer Figure 1). The composite sample was passed through a wet scrubber to break up the clays and attrition the ore prior to desliming the resulting slurry over a 38µm screen. The coarse material was fed to a gravity test circuit and the finer fraction (-38µm) was processed via froth flotation. The rougher (first stage) flotation concentrate generated from multiple, repetitive flotation tests were then blended to form the feedstock for a subsequent acid leach stage (refer Figure 2).

Two subsamples of flotation concentrate were leached under the following different conditions:

• Direct acid bake followed by hot water leach
• Dilute acid pre-leach followed by direct acid bake and hot water leach.

For both tests iron filings were added to the hot water wash phase to reduce the iron in the ferric (Fe3+) state to the ferrous (Fe2+) state, thus removing the iron from the solution. In this acid leach stage the titanium is recovered from the mineral concentrates into the liquor as titanyl sulphate (TiSO4) and the residue solids and liquor are then separated after the water leach step, using filtration, with the liquor moving forward for purification and product finishing testwork.

The next step in the purification process is the hydrolysis stage, which involves the heating of the liquor, thus breaking down the titanyl sulphate and resulting in the production of hydrated TiO2 and the recovery of H2SO4. This step was carried out in two stages without seed TiO2 material, an improvement from previous work. The solution was heated to 106 degrees C and held at temperature whilst being stirred for 2 hours. The resulting slurry was then centrifuged to separate the liquor from the precipitated solids. Finally, as part of the product finishing stage, the hydrated TiO2 was separated from the liquor using a centrifuge, and the solids were then calcined to remove water and produce a high-purity TiO2 compound (see figure 3).

The final chemical analysis of the TiO2 product indicates a very high purity of 99.25% TiO2 by mass with non-detectable or extremely low amounts of deleterious impurities (see table 1).

Figure 1. Saprolite composite sample before scrubbing/attritioning.

Figure 2. Flotation test on the saprolite composite slimes fraction

Table 1. Finished Product Analysis

Figure 3. Purification and product finishing testwork, photos from left to right: titanyl sulphate solution from leaching stage, hydrated TiO2 produced from hydrolysis, and the calcined TiO2 product.

The Pitfield Titanium Project

Figure 4. Pitfield Project Location showing the Mid-West Region Infrastructure and Services.