Solvent Extraction of Strontium from Leach Liquor of Central Iran Metasomatic Ores Using Macrocyclic Crown Ether Ligands

Document Type : Research Paper

Authors

1 Assoc. prof., Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran

2 MSc Graduate Student, Dept. of Chemical Engineering, Collage of Engineering, University of Tehran, Tehran, Iran

3 Prof., Dept. of Chemical Engineering, Collage of Engineering, University of Tehran, Tehran, Iran

4 Assist. prof., Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran

Abstract

Strontium is one of the alkaline earth metals in the periodic table. This element has various uses. In this research, solvent extraction of strontium from leach liquor of central Iran metasomatic ores was studied with macrocyclic crown ether ligands. Many crown ethers were used as extractants. Strontium was quantitatively extracted from picrate media by dicyclohexyl 18-crown-6 (DCH18-C-6) in 1,2-dichloroethane, and determined by flame emission spectrometry. Here, the factors affecting SX of Sr from synthetic solutions of strontium (containing 40 mg/L Sr) in sulfuric acid medium were identified. 0.01 mol/L DCH18C6 in 1,2-dichloroethane, 0.01 mol/L picric acid in aqueous phase, aqueous to organic (A/O) ratio of 1, pH 4 and extraction time of 5 min are the optimum values for affective factors. The precipitation with sodium hydroxide was conducted to remove the leaching impurities such as Fe, Mg, Al. Under optimal conditions, strontium extraction from leaching filtrate of metacomatic ores of central Iran (pH=2.7), in the presence of 0.01 mol/L picric acid, using 0.01M DCH18-C-6 in 1,2-dichloroethane was performed with a yield of 92.3%. The Sr stripping was obtained with 6 mol/L of hydrochloric acid, with A/O volume ratio of 1:1, with a yield of ~60%.

Keywords


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