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KR-20260063273-A - MAGNESIUM HYDROXIDE SLURRY AND MANUFACTURING METHOD OF THEREOF

KR20260063273AKR 20260063273 AKR20260063273 AKR 20260063273AKR-20260063273-A

Abstract

The present invention provides a magnesium hydroxide slurry comprising a first dispersant, a second dispersant, Mg(OH) 2 , and the remainder being water, wherein the content of Mg(OH) 2 is 50 wt% or more with respect to 100 wt% of the total slurry, the content of the first dispersant is in the range of 0.5 to 2 wt% with respect to 100 wt% of the total Mg(OH) 2 , the content of the second dispersant is in the range of 0.03 to 0.1 wt% with respect to 100 wt% of the total Mg(OH ) 2, and the Hydrodrophilic Lipophilic Balance (HLB) values of the first dispersant and the second dispersant independently satisfy the range of 8 to 20.

Inventors

  • 신길재
  • 이주훈
  • 권다혜

Assignees

  • (주)포스코퓨처엠

Dates

Publication Date
20260507
Application Date
20241030

Claims (17)

  1. Comprising a first dispersant, a second dispersant, Mg(OH) ₂ , and the remainder being water, The content of the above Mg(OH) ₂ is 50 wt% or more with respect to 100 wt% of the total slurry, and The content of the first dispersant is in the range of 0.5 to 2 wt% with respect to the total 100 wt% of Mg(OH) ₂ , and The content of the second dispersant is in the range of 0.03 to 0.1 wt% with respect to the total 100 wt% of Mg(OH) ₂ , and The HLB (Hydrophilic lipophilic balance) values of the first dispersant and the second dispersant are independently in the range of 8 to 20, Magnesium hydroxide slurry.
  2. In paragraph 1, The HLB value of the first dispersant is in the range of 8 to 15, Magnesium hydroxide slurry.
  3. In paragraph 1, The HLB value of the second dispersant is in the range of 12 to 18, Magnesium hydroxide slurry.
  4. In paragraph 1, The above slurry further includes a coagulant, and The content of the above coagulant is greater than 0 and less than or equal to 800 ppm with respect to the above slurry, Magnesium hydroxide slurry.
  5. In paragraph 1, Satisfying Equation 1 below, Magnesium hydroxide slurry. [Equation 1] 1 ≤ P 3 / P 1 ≤ 6 (In Equation 1 above, Pn represents the viscosity at the time point n of the magnesium hydroxide slurry storage.)
  6. In paragraph 1, Satisfying Equation 2 below, Magnesium hydroxide slurry. [Equation 2] 2 ≤ P 4 / P 1 < 40 (In Equation 2 above, Pn represents the viscosity at the time point n of the magnesium hydroxide slurry storage.)
  7. In paragraph 6, The above P 4 is in the range of 200 to 1000 cp, Magnesium hydroxide slurry.
  8. In paragraph 1, Satisfying Equation 3 below, Magnesium hydroxide slurry. [Equation 3] 1 ≤ P 3 / P 2 ≤ 1.8 (In Equation 3 above, Pn represents the viscosity at the time point n of the magnesium hydroxide slurry storage.)
  9. In paragraph 1, The first dispersant comprises at least one of organic acids, polycarboxylates, polyacrylates, polyacrylate copolymers, acrylics, salts thereof, lignosulfonates, polyethylene glycol, polyacrylamide, pyrobosate, sodium citrate, and ammonium citrate. Magnesium hydroxide slurry.
  10. In paragraph 1, The second dispersant is a phosphate-based material comprising at least one of sodium monophosphate, sodium diphosphate, sodium triphosphate, potassium monophosphate, potassium diphosphate, potassium triphosphate, sodium pyrophosphate, potassium pyrophosphate, sodium tripolyphosphate, sodium acid pyrophosphate, sodium hexametaphosphate, and sodium metaphosphate. Magnesium hydroxide slurry.
  11. (S1) A step of forming a low-concentration slurry by adding a coagulant to seawater; (S2) A step of preparing a high-concentration slurry containing 50 wt% or more of Mg(OH) ₂ relative to 100 wt% of the total by filtering the low-concentration slurry using a centrifugal dehydrator; and (S3) A step of adjusting the concentration by simultaneously introducing the above high-concentration slurry, the first dispersant, the second dispersant, and water into a stirrer; comprising, The above steps (S2) and (S3) proceed continuously. Method for preparing magnesium hydroxide slurry.
  12. In Paragraph 11, In the above step (S1), the coagulant is added to the high-concentration slurry such that the concentration is 800 ppm or less. Method for preparing magnesium hydroxide slurry.
  13. In Paragraph 11, In the above step (S1), the coagulant comprises a cationic polymer compound, Method for preparing magnesium hydroxide slurry.
  14. In Paragraph 13, The above cationic polymer compound comprises at least one of polyacrylamide, polyethyleneamine, polydiallyldimethylammonium chloride, polyamine, epichlorohydrin, and diethylenetriamine, Method for preparing magnesium hydroxide slurry.
  15. In Paragraph 11, In step (S3) above, the HLB (Hydrophilic lipophilic balance) values of the first dispersant and the second dispersant are independently in the range of 8 to 20, Method for preparing magnesium hydroxide slurry.
  16. In paragraph 15, The HLB value of the first dispersant is in the range of 8 to 15, Method for preparing magnesium hydroxide slurry.
  17. In paragraph 15, The HLB value of the second dispersant is in the range of 12 to 18, Method for preparing magnesium hydroxide slurry.

Description

Magnesium hydroxide slurry and manufacturing method of the same The present invention relates to a magnesium hydroxide slurry, and specifically to a method for producing a magnesium hydroxide slurry from seawater. Magnesium hydroxide slurry is widely applied in various fields, including industrial sectors such as pharmaceuticals, food additives, flame retardants, and gas desulfurization, as well as environmentally friendly applications such as wastewater treatment. Natural magnesium hydroxide slurry is prepared through a hydration reaction with magnesium oxide and the particle size is adjusted by wet grinding. Considering viscosity and storage stability, this natural magnesium hydroxide slurry is prepared by adding approximately 2.5 wt% of a dispersant based on the solid content. On the other hand, synthetic magnesium hydroxide slurry is produced by reacting Mg ions present in seawater with an alkaline precipitating agent through an ion exchange chemical reaction, and unlike the production of natural magnesium hydroxide slurry, a coagulant is added to facilitate the dehydration reaction. Consequently, compared to natural magnesium hydroxide slurry, synthetic magnesium hydroxide slurry suffers from problems such as a rapid increase in viscosity and hardening of precipitates when a dispersant is added. This impairs fluidity and storage stability, which currently acts as an obstacle to the commercialization of synthetic magnesium hydroxide slurry. In addition, magnesium hydroxide slurries are classified into low concentration and high concentration depending on the concentration of Mg(OH) ₂ contained therein, but high concentration magnesium hydroxide slurries tend to lose fluidity, which causes the aforementioned problems. Accordingly, the present invention aims to provide a synthetic magnesium hydroxide slurry and a method for manufacturing the same, which solves the aforementioned problems and secures the fluidity and storage stability of the natural magnesium hydroxide slurry. The technical terms used herein are for the reference of specific embodiments only and are not intended to limit the invention. The singular forms used herein include plural forms unless phrases clearly indicate otherwise. As used in the specification, the meaning of "comprising" specifies certain characteristics, areas, integers, steps, actions, elements, and/or components, and does not exclude the presence or addition of other characteristics, areas, integers, steps, actions, elements, and/or components. When it is stated that one part is "above" or "on" another part, it may be directly above or on the other part, or other parts may be involved in between. In contrast, when it is stated that one part is "directly above" another part, no other parts are interposed in between. Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with relevant technical literature and the present disclosure, and are not interpreted in an ideal or highly formal sense unless otherwise defined. Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and are not intended to limit the present invention, and the present invention is defined only by the scope of the claims set forth below. magnesium hydroxide slurry In one embodiment of the present invention, a magnesium hydroxide slurry is provided that solves the aforementioned problems by adding a first dispersant and a second dispersant having different HLB (Hydrophilic lipophilic balance), thereby having high fluidity and storage stability and reduced hardening of the precipitate. In one embodiment, the magnesium hydroxide slurry comprises a first dispersant, a second dispersant, Mg(OH) 2 , and the remainder being water, wherein the content of Mg(OH) 2 is 50 wt% or more with respect to 100 wt% of the total slurry, the content of the first dispersant is in the range of 0.5 to 2 wt% with respect to 100 wt% of the total Mg(OH) 2 , the content of the second dispersant is in the range of 0.03 to 0.1 wt% with respect to 100 wt% of the total Mg(OH) 2 , and the Hydrophlic Lipophilic Balance (HLB) values of the first dispersant and the second dispersant can independently satisfy a range of 8 to 20. The above HLB is a numerical representation of the degree of hydrophilicity and lipophilicity of the dispersant. HLB starts at 1 for the highest lipophilicity, and widely used dispersants generally have an HLB between 1 and 20. The HLB values of the first dispersant and the second dispersant can independently satisfy a range of 8 to 20. Specifically, 8 to 19, 8 to 18, 8 to 17, 8 to 16, 8 to 15, 8 to 14, 8 to 13, 9 to 20, 9 to 19, 9 to 18, 9 to 17, 9 to 16, 9 to 15, 9 to 14, 9 to 13, 10 to 20, 10 to 19, 10 to 18, 10 to