Sarytogan Graphite (ASX:SGA) reports it has achieved 99.87% graphite purity from metallurgical testwork at the Sarytogan Graphite Deposit in Central Kazakhstan.
The company says a composite sample was blended from samples collected from 3 diamond drillholes in the Northern Graphite Zone, and 3 from the Central Graphite Zone.
These samples were subjected to the same floatation and grinding steps used by Independent Metallurgical Operations (IMO) in Perth which achieved a premium micro-crystalline sizing of around 10 micron. The graphite purity achieved at this stage by Pro-Graphite was similar to IMO at 84% Total Graphitic Carbon (TGC), with a slight improvement due to the measurement method only.
Sarytogan Graphite Managing Director Sean Gregory says: “The company is thrilled with this breakthrough metallurgical results by our German laboratory partner Pro-Graphite.
“The company is thrilled with this breakthrough metallurgical results by our German laboratory partner Pro-Graphite”
The graphite purities achieved are a significant step towards battery anode specification. Sarytogan’s giant high-grade mineral resource is now complimented by its premium micro-crystalline high-purity product, credentials that now elevate the project to be a potential answer to the world’s projected battery anode material shortage.”
Sarytogan reports the floatation circuit was then upgraded by alkaline roasting at low-temperature with caustic soda and a weak sulphuric acid wash. A graphite purity of 99.70% TGC was achieved at this step, which is a significant improvement on the 92.1% TGC previously achieved by alkaline roasting.
Separately, the floatation concentrate was upgraded by chemical purification without the alkali roasting step also to a purity of 90.70% TGC.
Despite the identical purity results achieved by the alkaline purification and chemical purification separately, the different methods target different diluent minerals more effectively. The company reports combining both methods in series has been even more effective with 99.87% TGC achieved so far.
Sarytogan reports these results are another step toward the company’s strategy to target the rapidly growing battery and anode materials market. The product to support this strategy will be Uncoated Spherical Graphite (USpG).
According to the company, USpG presently trades at more than US$3,000 per tonne which is around triple the price of traditional flake graphite products.
To achieve the specification of USpG, the Sarytogan concentrates will require milling to make spherical graphite balls of 5um to 20um in size and further purification to 99.95% TGC.
Sarytogan states IMO are continuing to optimise the floatation process, experimenting with different grind methods and sizes, desliming, and alternative reagents all aimed at designing the most economic method to generate floatation concentrate at similar purities to that already achieved
Pro-Graphite continues to optimise the purification process, and the residue from these tests is being assayed to assess its mineralogy and devise further process improvements, such as alternative acids aimed at achieving even ‘higher’ purities.
The company says Pro-Graphite are also planning initial spheroidisation tests to determine the product yield and physical properties of Sarytogan USpG.
This will require additional floatation concentrate to be manufactured, a requirement that is expected to grow as the project advances and for future customer samples.
To get ahead of this demand, Sarytogan is in discussions with several laboratories to upscale the production of floatation concentrate. The HQ drilling program on site has now been completed, and further drilling results announcements are planned as assays become available.
The company also notes the planned mineral resource upgrade targeting indicated classification is on track for Q1 2023.
Sarytogan Graphite is a graphite producer that wholly owns the Sarytogan Graphite Deposit located in the Karaganda region of Central Kazakhstan. The project is located 190km from the city of Karaganda, and it currently hosts an inferred mineral resource of 209 million tonnes @ 28.5% TGC for 60 million tonnes of contained graphite estimated by CSA Global.
Images: Sarytogan Graphite Ltd & iStock
