Complete Recuperation of Lithium in Leach
Montreal, March 31, 2019 / TheNewswire / St-Georges Eco-Mining Corp. (CSE: SX) (OTC: SXOOF) (FSE: 85G1) is pleased to inform its shareholders that it can confirm that it has achieved complete and total recovery in leach of lithium from the bulk material provided by its partner Iconic Minerals (TSX-V: ICM) originating from their Bonnie Claire lithium project in Nevada.
St-Georges' patent pending leaching technology achieved 100% leaching of lithium while not affecting the majority of the solids. 88% of the initial feed material is unleached which helps with chemicals consumption and tailings disposal.
The patent pending mix of nitric and citric acids being used do not require high temperature and high pressure and no calcination is required. The objectives of the technology development was simply to have the lowest chemical cost impact.
The impacts on the Bonnie Claire Deposit of the first phase of the process that includes classification, concentration and leaching at atmospheric pressure and low temperature has shown an average concentration gain from 963 ppm Li to 8,025 ppm Li, or a gain of 8,333 percent.
St-Georges is currently testing different calibration and improving on its selective leaching in order to target only the recuperation in the leach of the lithium and magnesium and achieve better grades in the leach.
In addition to the lithium, the selective leaching collects mainly the salt family elements such as Sodium (Na), Magnesium (Mg), Calcium (Ca) and items like carbonates. The company believe that this could lead to-possible development of fertilizer by-products in the nitrate family that would potentially positively impact the economics of the Bonnie Claire project.
The next tests to be started this week will focus on reducing the total time of contact and we expect that the selectivity will be increased. In addition, St-Georges is in the process of purchasing a electrolysis unit to make LiOH to be added to the pilot plant with a further focus on using less chemicals. Work with various vendors of resins has been initiated to optimize the lithium purification steps prior to lithium hydroxide production.
The phase 1 confidential report is currently being independently reviewed and a final public summary should be disseminated within 45 days. Detailed tests result and confidential information related to the process flow-sheet has been provided to Iconic management. For details and guidelines regulating the relation between Iconic and St-Georges, please read December 7, 2017 press release "Licensing Technology Agreement with Iconic Minerals".
Two approaches were developed and tested. Air classification and flotation concentration. These co-exist as linear task A and B of the concentration step at this stage. St-Georges is currently working on eliminating one of the sub-tasks with the hopes of drastically reducing costs and processing time.
In this step the material is separated by density and particle size. In the particular case of the Bonnie Claire material, the lithium is contained in the superfine particles. These particles are too fine to be screened.
Independent review and testing of Task 3a were performed in the scope of the month of November 2018 by the laboratories of Netzsch Premier Technologies LLC of Exton, Pennsylvania. The resulting material was reduced by 55% with a cut-off at 5 microns.
The CTMP labs performed, at the demand of St-Georges, a traditional froth floatation with deionized water. These tests were unsuccessful forcing the company metallurgists to adopt a different approach.
100% of the lithium was leached at atmosphere pressure and low temperature. The total leach time was of 1 hour resulting in 12% of the initial total mass. The company set-up and intends to improve on that result.
Material from this leach test was passed through tasks 1, 2 and 3a. 100% of the lithium was leached at atmosphere pressure and low temperature. The total leach time was of 1 hour resulting in 12% of the initial total mass.