Flotation Separation Methods On Lithium And Magnesium And The Application Research Of Extracting Lithium From The Salt Lake Bitterns

Floating separation technology was a separation method that introduced in chemical field early in 1932, Nevertheless a new floating method-solvent flotation has come up not until 1962, when floatating separation technology drew the attention of scientific and technical workers. Now, floating separation method is making great progress, and the theory and technology are becoming more and more systematic. In this paper, we will use the floating technology for the separation and accumulation of lithium in the salt lake bittern, and will compare compared this method with solvent extraction. The result showed that the effects on the separation and accumulation of lithium was optimized by flotation .TBP system was discussed first in this paper. The optimal flotating and enrichment conditions are determined through a series of single factor experiments. The mechanism of the flotation was discussed preliminarily through the experiments of TBP system. It is perceived that the reaction of FeCl₃ with Cl^- come first, and then the formation of associating content LiFeCl₄ with Li⁺ followed on. It absorbed on the rising bubbles in the aqueous solution of the flotation column. Then was brought into organic layers, forming a stable compounds LiFeCl4?2TBP by the function from P=O base in TBP. Thus the result on enrichment and separation of lithium was reached. Based on the cognition of original floatation column and the identity of the viewpoint from predecessors in laboratory, the shape of the floatation column was improved. The result showed that the improved B-4 floatation column had the best effect. The question about the "border mergers layer " was almost resolved and the separation conditions of lithium and magnesium were optimized by the improved floatation column.Experiment about temperature makes use of the floatation column, which covers the jacket, the conclusion was that the lower the temperature was and the was more beneficial the floatation concentration of lithium. Because the lower the tempreture was, the more benefiticial to the absorption of the material difficult to disintegrate and macromolecular substances. The floatation was proved that the stay enrichment content sticked or adsorbed on the surface of the bubbles, and then rose into organic phase with the bubbles rising. So the enrichment rate was above the average to the floatation. Therefore, floatation had the higher floatation concentration rate.In the paper also probed into the phenanthroline system. By the current work perspective, the separation result of lithium and magnesium were not good by using the phenanthroline system. Magnesium had high interference. Because of the massive existence of magnesium, salting-out effect on the derichment of lithium was produced, and high derichment rate of lithium was achieved.This paper used improved floatation column to separate and enrich the lithium in the salt lake brine. Also it determined the effect of separation and enrichment by atomic absorption spectrometry. The straight shape floatation column of separation and enrichment rate and reverse enrichment rate for lithium were between 85% and 90%. however that of the spherical floatation column were up to 90%, thus, the floatation column which was improved in this thesis could be comprehended that separating and the separation and enrichment of lithium in salt lake bittern effectively.