Preparation method of submicron magnesium hydroxide

[0023] Example 1

[0024] Configure MgCl separately 2 500mL each of the aqueous solution and the mixed aqueous solution of NaOH and NaCl, of which MgCl 2 The concentration is 1.0 mol/L, the NaOH concentration is 1.6 mol/L, and the NaCl concentration is 2.4 mol/L. Both of the above two aqueous solutions enter the microreactor at a flow rate of 150mL/min for contact, mixing and reaction, n(Mg 2+ ):n(OH - )=1:1.6, and the reaction temperature is 60°C. After the reaction slurry flows out from the outlet of the microreactor, it directly enters the hydrothermal synthesis kettle, and undergoes hydrothermal treatment at 180° C., and the hydrothermal time is 4 hours. After the hydrothermal treatment, 200 mL of the reaction slurry after the hydrothermal reaction was placed in a Buchner funnel with an inner diameter of 9 cm for vacuum filtration, and the filtration time was determined to be 500 s. After washing with deionized water for three times, it was placed in an oven to dry for 6 hours to obtain submicron magnesium hydroxide. The SEM photo of the obtained magnesium hydroxide is as follows figure 1 As shown, the average particle size is 775 nm.

[0025] Example 2

[0026] Configure MgCl separately 2 500mL each of the aqueous solution and the mixed aqueous solution of NaOH and NaCl, of which MgCl 2 The concentration is 0.5 mol/L, the NaOH concentration is 1.0 mol/L, and the NaCl concentration is 3.0 mol/L. Both of the above two aqueous solutions enter the microreactor at a flow rate of 150mL/min for contact, mixing and reaction, n(Mg 2+ ):n(OH - )=1:2.0, and the reaction temperature is 60°C. After the reaction slurry flows out from the outlet of the microreactor, it directly enters the hydrothermal synthesis kettle, and undergoes hydrothermal treatment at 180° C., and the hydrothermal time is 4 hours. After the hydrothermal treatment, 200 mL of the reaction slurry after the hydrothermal reaction was placed in a Buchner funnel with an inner diameter of 9 cm for vacuum filtration, and the filtration time was determined to be 420 s. After washing with deionized water for three times, it was placed in an oven to dry for 6 hours to obtain submicron magnesium hydroxide. The SEM photo of the obtained magnesium hydroxide is as follows figure 2 As shown, the average particle size is 840 nm.