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CN-121976252-A - Method for preparing high-purity zinc based on zinc sulfate system and high-purity zinc

CN121976252ACN 121976252 ACN121976252 ACN 121976252ACN-121976252-A

Abstract

The invention discloses a method for preparing high-purity zinc based on a zinc sulfate system and the high-purity zinc, aiming at the problem that the electrolytic new solution in the preparation of the high-purity zinc by electrolysis of the zinc sulfate system is high in impurity content, chemical pure 98% concentrated sulfuric acid, water with conductivity less than 10 mu S/cm, hydrogen peroxide conforming to the standard of 27.5% superior products of GB/T1616-2014 and metallic zinc with impurity content conforming to the standard of Zn99.995 of GB/T470-2008 are adopted as raw materials, the sources of impurities are controlled, the solution with the zinc ion concentration of 120-140 g/L is prepared, the pH value of the obtained solution is controlled to be 2-5.5 by adding sulfuric acid, and finally bone glue solution is added, so that the low-impurity electrolyte with low impurity content is prepared. The low-impurity electrolyte prepared by the invention can be used for preparing high-purity zinc with the concentration of more than 5N by electrolysis.

Inventors

  • ZHOU YULIN
  • LUO LI
  • WANG WENJUN
  • LIAO ZHOU
  • DAI HUIMIN
  • YUAN TIECHUI
  • ZHANG YIBO
  • TIAN MENGJIE
  • HU JUN

Assignees

  • 湖南有色金属控股集团有限公司
  • 中南大学

Dates

Publication Date
20260505
Application Date
20260109

Claims (10)

  1. 1. A method for preparing high-purity zinc based on a zinc sulfate system is characterized by comprising the following steps of, Adding water to a constant volume after mixing concentrated sulfuric acid and hydrogen peroxide, adding excessive metal zinc into the stirring solution until the metal zinc is not dissolved any more, and filtering to obtain a zinc sulfate solution; adding bone glue and dilute sulfuric acid into the zinc sulfate solution, and stirring until the bone glue is completely dissolved, thus obtaining low-impurity zinc electrolyte; the low-impurity zinc electrolyte is used as a solution carrier to be electrified, sulfuric acid is added according to the pH value of a preset solution during the electrifying process, and bone glue is added according to the mass ratio of the preset zinc product to the bone glue, so that the high-purity zinc product can be obtained.
  2. 2. A process for preparing high-purity zinc on the basis of zinc sulfate systems as claimed in claim 1, wherein the mass ratio of concentrated sulfuric acid to hydrogen peroxide is 1:1.
  3. 3. The method for preparing high-purity zinc based on zinc sulfate system according to claim 1, wherein the metal zinc is one or more of zinc ingots, zinc sheets and zinc powder.
  4. 4. The method for preparing high-purity zinc on the basis of zinc sulfate system as claimed in claim 1 or 3, wherein the addition amount of the metallic zinc is 1.1-1.5 times of the theoretical amount.
  5. 5. The method for preparing high-purity zinc based on zinc sulfate system according to claim 1, wherein the concentration of bone glue added into the zinc sulfate solution is 0.01-0.1 g/L.
  6. 6. The method for preparing high-purity zinc based on zinc sulfate system according to claim 1 or 5, wherein the amount of dilute sulfuric acid added into the zinc sulfate solution is controlled to be 2-5.5 according to the pH value of the solution.
  7. 7. The method for preparing high-purity zinc based on zinc sulfate system according to claim 1, wherein the condition of energizing with low-impurity zinc electrolyte as solution carrier comprises, The low-impurity zinc electrolyte is used as electrolyte, zinc is used as anode, 316L stainless steel is used as cathode, the zinc anode is sleeved with diaphragm bags, the cathodes and the anodes are uniformly distributed at intervals, the homopolar distance is 7-11 cm, the current density is 100-400A/m 2 , and the cathode slot outlet time is 24-96 h.
  8. 8. The method for preparing high-purity zinc based on zinc sulfate system according to claim 1 or 7, wherein sulfuric acid is added in a controlled manner according to pH of 2-5.5 during the power-on period.
  9. 9. The method for preparing high-purity zinc based on a zinc sulfate system according to claim 8, wherein the bone cement is added in a mass ratio of zinc product to bone cement of 5000-20000:1 during the energizing period.
  10. 10. The high-purity zinc prepared by the method according to any one of claims 1 to 9, wherein the impurity content of the high-purity zinc is less than 0.7X10 -4 %.

Description

Method for preparing high-purity zinc based on zinc sulfate system and high-purity zinc Technical Field The invention belongs to the technical field of preparing high-purity zinc by an electrolytic method, and particularly relates to a method for preparing high-purity zinc based on a zinc sulfate system and the high-purity zinc. Background The existing preparation method of high-purity zinc with purity of more than 99.999 percent mainly comprises a zone smelting method, a vacuum distillation method and an electrolysis method. The method for preparing high-purity zinc by zone smelting is based on segregation effect for separation and purification, and utilizes the difference of chemical potential of impurity elements in main metal solidification state and molten state two phases at the same temperature to migrate and separate impurities by repeated melting-solidification, so that the method has the defects of low direct yield, high energy consumption, long production period and the like, and restricts the development and application of the technology. The vacuum distillation method mainly utilizes the saturated vapor pressure difference of metallic zinc and impurities to remove impurities, can effectively remove impurities with larger difference between the melting boiling point and the zinc, but has poor impurity removing effect on impurities with similar melting boiling point, is difficult to realize deep impurity removal by one-step distillation, has the defects of high energy consumption, low direct yield and the like, and is difficult to realize large-scale production. The electrolytic method has the advantages of high metal direct yield, low energy consumption and the like, but the problems of difficult impurity metal control and the like in the electrolytic process are solved because the electrolyte prepared at present contains high impurities, and the qualified high-purity zinc product is difficult to prepare. Currently, research on preparing high-purity zinc by aiming at a zinc sulfate system exists in the prior art, for example, a method for preparing high-grade zinc by an electrolytic method and application thereof (application number 201511028046.5) are disclosed in the patent publication, a zinc sulfate solution subjected to deep iron precipitation and copper removal is adopted as electrolyte, pb-Ag alloy is adopted as an anode, an aluminum plate is adopted as a cathode, and zinc products are further obtained through electrolysis, and as the impurity content in the electrolyte is still higher, the obtained zinc products contain Pb of 1.7x -4%, cu of 1.6x -4%, fe of 2.2x -4%, sn of 1.1x -4% and Al of 2.1x -4% and exceed the Pb, cu, fe, sn, al standard of Zn-05 in YS/T920-2013 standard. Disclosure of Invention This section is intended to outline some aspects of embodiments of the application and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application. The present invention has been made in view of the above and/or problems occurring in the prior art. Therefore, the invention aims to overcome the defects in the prior art and provide a method for preparing high-purity zinc based on a zinc sulfate system. In order to solve the technical problems, the invention provides the following technical proposal that comprises, Adding water to a certain volume after mixing concentrated sulfuric acid and hydrogen peroxide, adding excessive metal zinc into the solution while stirring the solution until the metal zinc is not dissolved any more, and filtering after stirring to obtain a zinc sulfate solution; Adding deionized water into the zinc sulfate solution to fix the volume, adding bone glue and dilute sulfuric acid into the solution, and stirring until the bone glue is completely dissolved, thus obtaining low-impurity zinc electrolyte; And electrifying by taking the low-impurity zinc electrolyte as a solution carrier to obtain a high-purity zinc product. As a preferable scheme of the method for preparing high-purity zinc based on the zinc sulfate system, the concentrated sulfuric acid is chemically pure concentrated sulfuric acid, the water is water with the conductivity of less than 10 mu S/cm, and the hydrogen peroxide is hydrogen peroxide which accords with 27.5% of high-grade standard of GB/T1616-2014. As a preferable scheme of the method for preparing high-purity zinc based on the zinc sulfate system, the mass ratio of the concentrated sulfuric acid to the hydrogen peroxide is 1:1. The method for preparing high-purity zinc based on the zinc sulfate system is a preferable scheme, wherein the metal zinc is one or more of zinc ingots, zinc sheets and zinc powder, and the metal zinc is selected to be a zinc raw material, and the impurity content of the metal zinc meets the requirements of Zn99.995 standard in G