Method and system for enriching lithium from sodium aluminate solution in an alumina plant

Abstract

The invention discloses a method and system for enriching lithium from a sodium aluminate solution in an alumina factory. The method includes exchanging heat and cooling the lithium-containing sodium aluminate solution, reacting with an aluminum hydroxide adsorbent to precipitate lithium, and collecting the lithium after filtering. The filter cake is reheated and re-dissolved, the re-dissolved slurry is filtered, the obtained second filter cake is filtered after being slurried, and countercurrent washed for many times, and the obtained third filter cake is the lithium-rich adsorbent; the system includes Adsorption assembly, adsorbent preparation tank, first centrifugal pump, primary heat exchanger, secondary heat exchanger, first filter assembly, redissolving assembly, second filter assembly, second centrifugal pump, third filter assembly, and second filter assembly Three centrifugal pumps. The present invention proposes for the first time and uses aluminum hydroxide seed crystals to prepare an adsorbent to adsorb lithium in a lithium-rich sodium aluminate solution system, realizing efficient separation of lithium; utilizing cooling adsorption and rapid heating filtration to achieve rapid and efficient separation; through adsorption The further enrichment of lithium in the adsorbent by solvent redissolution creates favorable conditions for the subsequent extraction of lithium salts.

Description

technical field [0001] The invention belongs to the technical field of inorganic chemical industry, and relates to a method for extracting high value-added lithium salt from the semen of alumina produced by Bayer method or sintering method, in particular to a method for enriching lithium from sodium aluminate solution in an alumina factory methods and systems. Background technique [0002] Lithium carbonate, an inorganic compound with the formula Li 2 CO 3 , as colorless monoclinic crystals or white powder. Density 2.11g / cm 3 , Melting point 618℃, soluble in dilute acid, slightly soluble in water, more soluble in cold water than hot water, insoluble in alcohol and acetone. Widely used in batteries, ceramic glass, lubricants, pharmaceuticals and other industries. [0003] Lithium carbonate is the basic material for the production of secondary lithium salts and lithium metal products, so it has become the most used lithium product in the lithium industry, and other lithiu...

AI Technical Summary

Problems solved by technology

[0011] It can be seen from Table 1 that Li in the products of alumina factories in central my country 2 O is generally high, usually imported alumina Li 2 O is only 0.006%. If it is estimated at 0.1%, the alumina production is estimated at 12 million tons / year, and the Li 2 O is as high as 12,000 tons. These lithium resources have not been rationally utilized. What's more, the lithium enrichment in the electrolyte of the electrolysis plant that uses lithium-rich alumina as raw material for a long time exceeds a reasonable range, which leads to the deterioration of the working conditions of the electrolysis cell, which in turn has to be limited Lithium-rich alumina

[0012] After checking the relevant literature at home and abroad, there is no report on the enrichment of lithium from the sodium aluminate solution in the alumina factory

Images