section Home
Production, Amateur
Radio amateur
Model aircraft, rocket-
Useful, entertaining 		Stealth master
Electronics
Physics
Technologies
invention 		space Mystery
Earth Mysteries
Secrets of the Ocean
Stealth
section Map
Start
Forum
Use of material is permitted for reference (for websites - hyperlinks)
INVENTION
Russian Federation Patent RU2091306

Way to extract lithium from magnesium chloride solution

Way to extract lithium from magnesium chloride solution

Name of the inventor: Samoilov YM .; Isupov VP
The name of the patentee: Institute of Solid State Chemistry and Mineral Processing, SB RAS; Yury Samoilov; Isupov Vitaly
Address for correspondence:
Starting date of the patent: 1993.05.31

Uses: hydrometallurgy rare alkali metals. Essence: the extraction of lithium chloride solutions using Fe-containing tributyl phosphate (Fe org = 0.2-0.6 M) with the addition of a carboxylic acid. Volume of the organic phase with lithium extraction reaches a value of 33.5 g / l. Lithium stripping of the organic phase is carried out with 4-6 molar hydrochloric acid, and the iron remains in the organic phase, and reextract the lithium content is 15-20 g / l.

DESCRIPTION OF THE INVENTION

The invention relates to hydrometallurgy rare alkaline elements, in particular to the extraction of lithium from solutions of magnesium chloride.

A method is known lithium extraction from brine containing mainly magnesium chloride, by introducing into it ferric chloride, followed by extraction of the resulting tetragaloferrata lithium diisobutyl ketone, stripping lithium iron water purification from iron lithiated reextract other extractant (D2EHPA-TBP), ferric chloride regeneration return it to the process head (prototype).

The disadvantages are the complexity of the technology (multiple layers, the necessity of using two extraction branches with different extractants regeneration of ferric chloride and enough concentrated and lithium on the final solution, which complicates isolation of the desired product.

Object of the invention simplify the process of extraction of lithium chloride solutions to produce more concentrated solutions 1. The problem solved by a method, in which extraction of lithium magnesium chloride solution containing Fe-carried tributilfocfatom (TBP), with the addition of carboxylic acid and lithium stripping carried hydrochloric acid .

Hallmarks of this method are: the use of Fe-containing TBP (FeCl 3 in a known source is introduced into the aqueous solution and extractant diisobutyl-TBP and D2EHPA); reextraction solution of HCl (in the famous - water).

Using the proposed composition of the extractant creates the conditions in which the iron is retained in the organic phase, which can significantly simplify the process of technology: no need to strip liquor purification from iron and returning it to the cycle. And adding to the extractant carboxylic acid prevents the formation of iron hydroxide sludge which impedes stratification phase in the extraction system.

To identify the optimal process conditions were studied on samples containing varying amounts of magnesium, lithium, ratio O: B, iron concentrations of TBP, etc.

From data on the extraction of lithium Fe-containing TBP tabulated. 1, it is seen that the iron quantitatively (97.3% of 100) MgCl 2 February concentration mol / L (48.6 g / L Mg) is in the extractant, and extraction of lithium is 60-77% (Examples 5, 6, 9 -11, 13-15), which, counterflow mode allows to quantitatively extract lithium. The conditions of Examples 5 and 6 (diisobutyl, the prototype) is extracted at least 20% lithium.

For lithium stripping of the organic phase (see. Table. 2) it is necessary to use hydrochloric acid at a concentration of 4 M or more, wherein the iron remains in the extractant, and lithium on 80-88,5% goes into the aqueous phase.

The organic phase from re-extraction hydrochloric acid solution (HFeCl 4 TBP) is treated with an alkaline reagent (any) in the presence of magnesium chloride to convert the oxide form of the iron complex salt, and is sent back to the extraction cycle.

Example 1. prepared solution containing 0.103 g / l of 3M MgCl 2 (Mg 72,9 g / l). Extraction was carried out with different volume ratio O: B 2: 1, 1: 1, 1: 2, 1: 5 and 1:10 for 3 min. extractant at pH 2. 10 g / l Fe + TBP in 10% caprylic acid. The resulting organic phase was treated with 4 M HCl solution for lithium stripping at O: B 1: 1. Removing the lithium was as follows: 69.0 68.0 65.0 56.0 and 27%, respectively.

Example 2. Example 1 A solution was extracted with a mixture of components in Example 1, but the content of Fe in the extractant 30 g / l, the ratio of O: B 1: 5. A lithium extraction was 80%

Example 3. Prepared solution wherein 4 g / l, MgCl 2 2,5 M (60,75 g / l Mg) with the other conditions on the forward one but the content of Fe in the extractant 33.5 g / l 0:. The 1: 1. The resultant extract contained 3.05 g / l and treated with 6 M HCl solution at O: B 1: 1, 5: 1 and 10: 1.

The concentration of lithium was re-extract, g / l: 13.1 2.7 and 18.6 (degree of stripping 89, 86 and 61%), residual Fe was 0.14 0.01 and 0.001 g / L, respectively.

For the experiments, you can take any of the carboxylic acids, slightly soluble in water. Generally, this acid with a carbon number greater than 8. The use of carboxylic acids with high solubility leads to considerable losses in the acid during the experiment.

CLAIM

Method of extracting lithium from solutions of magnesium chloride which includes extraction with an organic extractant followed by re-extraction of the target product, wherein the iron-lead extraction with tributyl phosphate additive is not water soluble carboxylic acid and lithium stripping carried hydrochloric acid.

print version
Publication date 15.03.2007gg