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CN-121990594-A - Method for extracting lithium and potassium from carbonate type salt lake brine

CN121990594ACN 121990594 ACN121990594 ACN 121990594ACN-121990594-A

Abstract

The invention discloses a method for extracting lithium and potassium from carbonate salt lake brine. The method comprises the steps of performing pre-evaporation treatment on carbonate salt lake brine to obtain first brine, performing Li + adsorption and analysis treatment on the first brine to obtain second brine and analysis solution, performing natural evaporation treatment on the analysis solution to obtain LiCl, and performing freezing, natural evaporation and cold crystallization treatment on the second brine to obtain KCl, so that extraction of lithium and potassium in the carbonate salt lake brine is realized. The invention constructs a salt lake resource development mode of 'lithium before potassium', specifically comprising a process of 'pre-evaporation-continuous ion exchange-freezing-natural evaporation-cold crystallization', realizes the resource utilization of lithium and potassium in carbonate salt lake brine, and improves the lithium yield.

Inventors

  • WU YUELIANG
  • WANG ZHANGXIANG
  • MA YANFANG
  • HUANG SHOUYAN
  • SHI XUJIE
  • LIU XIN

Assignees

  • 西藏中鑫投资有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (10)

  1. 1. A method for extracting lithium and potassium from carbonate type salt lake brine, which is characterized by comprising the following steps: pre-evaporating carbonate lake brine to obtain first brine; Performing Li+ adsorption and analysis treatment on the first brine to prepare second brine and analysis liquid; performing natural evaporation treatment on the analysis liquid to obtain LiCl; and freezing, naturally evaporating and cold crystallizing the second brine to obtain KCl, thereby realizing the extraction of lithium and potassium in the carbonate salt lake brine.
  2. 2. The method of claim 1, comprising the step of pre-evaporating carbonate lake brine in summer to obtain first brine, wherein the pre-evaporating treatment at least meets the condition that the concentration of K+ in the first brine is less than or equal to 2.00wt%.
  3. 3. The method of claim 1, wherein the carbonate salt lake brine comprises the following components ：K + 1.00～1.20wt％、Mg 2+ 0.02～0.06wt％、Li + 0.016～0.020wt％、Cl - 7.50～8.10wt％、SO 4 2- 1.15～1.25wt％ and 1.16-1.26wt% of CO 3 2- in percentage by mass.
  4. 4. The method according to claim 1, characterized in that it comprises in particular: Inputting the first brine into a continuous ion exchange device for Li + adsorption treatment to prepare second brine; analyzing the continuous ion exchange device by adopting 0.3-0.4 mol/L HCl solution to prepare analysis solution; Performing natural evaporation treatment on the analysis liquid to obtain third brine and a NaCl crude product, wherein the concentration of Li + in the third brine is 0.65-0.75wt%; And carrying out natural evaporation treatment on the third brine continuously to obtain a LiCl product.
  5. 5. The method of claim 4, wherein the LiCl product is produced in a yield of 90% or more.
  6. 6. The method according to claim 1, characterized in that it comprises in particular: freezing the second brine at the temperature of-17.0 to-13.0 ℃ and then carrying out solid-liquid separation to obtain fourth brine and a first solid product; Performing natural evaporation treatment on the fourth brine, and performing solid-liquid separation to obtain fifth brine and a second solid product, wherein the concentration of K + in the fifth brine is 3.30-3.40 wt%; and (3) continuing to perform natural evaporation treatment on the fifth brine, and stopping evaporation to perform solid-liquid separation when the mass ratio of the obtained brine to the carbonate salt lake brine is 2.5-3.5:100, so as to obtain sixth brine and a third solid product.
  7. 7. The method of claim 6, wherein the method specifically comprises the steps of adding the third solid product into a Na + -K + -Cl - saturated system with the temperature of 80-90 ℃ for dissolution, separating and filtering, and naturally cooling the obtained liquid product to obtain a KCl product and a liquid by-product.
  8. 8. The method of claim 7, wherein the KCl product yield is 65% or more.
  9. 9. The method of claim 7, wherein the liquid phase byproduct is recycled as a mother liquor.
  10. 10. The method of claim 6, wherein the first solid product and the second solid product are used to produce a sodium product.

Description

Method for extracting lithium and potassium from carbonate type salt lake brine Technical Field The invention belongs to the technical field of comprehensive utilization of salt lake brine resources, and particularly relates to a method for extracting lithium and potassium from carbonate salt lake brine. Background Lithium potassium in salt lake brine is an important resource. At present, the technology for extracting and separating potassium resources is relatively perfect and mature, and a complete industrial chain is formed, for example, an 800-ten thousand-ton potassium fertilizer production line is produced in the Qinghai salt lake industrial stock year, a potassium sulfate production line of a apocynum salt lake and the like. The research on the method for extracting and separating lithium from salt lake resources is very hot and hot, and meanwhile, several production lines are also shortened. For example, the blue industry, the Tibetan lattice lithium industry, the Jintai lithium industry, the five-ore industry, the Qinghai lithium industry, the constant-letter lithium industry, and the like. At present, no complete technology and industrialization demonstration are formed for simultaneously extracting lithium and potassium from carbonate type salt lake brine in China, for example, zabuyer salt lake is currently used for preparing lithium carbonate by a precipitation method, potassium resources are recycled in the later period, and the loss of lithium resources in the process is serious. The salt lake resource in Qinghai area firstly utilizes potassium resource, then the tail halogen is extracted with lithium, and the disadvantage of the process is that the lithium resource is seriously lost. Disclosure of Invention The invention mainly aims to provide a method for extracting lithium and potassium from carbonate type salt lake brine, which aims to overcome the defects of the prior art. In order to achieve the purpose of the invention, the technical scheme adopted by the invention comprises the following steps: the embodiment of the invention provides a method for extracting lithium and potassium from carbonate salt lake brine, which comprises the following steps: pre-evaporating carbonate lake brine to obtain first brine; performing Li + adsorption and analysis treatment on the first brine to prepare second brine and analysis liquid; performing natural evaporation treatment on the analysis liquid to obtain LiCl; and freezing, naturally evaporating and cold crystallizing the second brine to obtain KCl, thereby realizing the extraction of lithium and potassium in the carbonate salt lake brine. Compared with the prior art, the invention has the beneficial effects that the invention constructs a salt lake resource development mode of 'lithium before potassium', specifically comprises a process of 'pre-evaporation-continuous ion exchange-freezing-natural evaporation-cold crystallization', realizes the resource utilization of lithium and potassium in carbonate salt lake brine, and improves the lithium yield (the yield of the prior art is less than 90%). Drawings In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings may be obtained according to the drawings without inventive effort to those skilled in the art. Fig. 1 is a schematic diagram showing a process flow for extracting lithium and potassium from carbonate salt lake brine according to an exemplary embodiment of the invention. Detailed Description In view of the defects of the prior art, the inventor of the present invention has provided the technical proposal of the present invention through long-term research and a great deal of practice, and mainly establishes a process method of 'pre-evaporation-continuous ion exchange-freezing-natural evaporation-cold crystallization' of carbonate lake lithium potassium resources. The following description of the present invention will be made clearly and fully, and it is apparent that the embodiments described are some, but not all, of the embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. Specifically, as one aspect of the technical scheme of the invention, the method for extracting lithium and potassium from carbonate type salt lake brine comprises the following steps: pre-evaporating carbonate lake brine to obtain first brine; performing Li + adsorption and analysis treatment on the first brine to prepare second brine and analysis liquid; performing natural evaporation treatment on the