The invention relates to a method and a device for separating
magnesium and
lithium and enriching the
lithium from
salt lake brine. The method comprises the following steps of: separating an electrodialyzing device into two areas by using an anion exchange membrane, namely a
lithium salt chamber and a brine chamber, filling the
salt lake brine in the brine chamber, and filling a
supporting electrolyte solution which does not contain Mg<2+> in the lithium salt chamber; placing a conducting matrix coated by an ionic
sieve in the brine chamber as a
cathode; placing the conducting matrix coated by a lithium-embedded ionic
sieve in the lithium salt chamber as an
anode; under the driving of an external
electric potential, embedding Li <1+> in the brine in the brine chamber into the ionic
sieve to form the lithium-embedded ionic sieve, and recovering the lithium-embedded ionic sieve into the ionic sieve after the lithium-embedded ionic sieve in the lithium salt chamber releases the Li <1+> into a conducting solution; and discharging a liquid in the brine chamber after the lithium is embedded, adding the
salt lake brine again, alternatively placing electrodes in the two chambers, and repeating and circulating operations. Through the method and the device for separating
magnesium and lithium and enriching lithium in the
salt lake brine, the separation of the lithium and other ions is effectively realized, and a lithium-enriched solution is synchronously obtained. The method has a short flow and low production cost, is simple to operate, can be operated continuously, and is easy to industrially apply.