Method for extracting lithium from lithium clay

• Main Authors: BAO DONGLIAN, CHEN RUOKUI, NGUYEN DINH SON, QIAO YANCHAO, LI CHANGDONG, LI BO
• Format: Patent
• Language: Chinese; English
• Published: 11.10.2022
• Subjects: CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

The invention discloses a method for extracting lithium from lithium clay, which comprises the following steps: roasting lithium clay powder, grinding roasted clinker, mixing the ground roasted clinker with a leaching agent and water, leaching at the temperature of 150-300 DEG C and the pressure of 1.4-2.5 MPa, and carrying out solid-liquid separation to obtain a lithium-containing solution and leaching residues, the leaching agent is at least one of sodium hydroxide, potassium hydroxide, strong acid salt of sodium or strong acid salt of potassium, adding a proper amount of the leaching agent into the lithium-containing solution, returning to the step S2 for cyclic leaching, and carrying out cyclic leaching for several times according to the process to obtain a lithium-rich solution. According to the method, lithium in the lithium clay is selectively leached based on the ion exchange effect between Li < + > in the lithium clay ore and Na < + >/K < + > in the leaching agent at high temperature and high pressur