Amorphous zirconium hydroxide, its preparation method and use

Abstract

The present application relates to a kind of amorphous zirconium hydroxide and preparation method and application, its preparation method includes: (1) under dynamic condition, basic hydroxide, zirconium salt, additive is contacted in aqueous solution condition, the additive is acid and / or acid salt;(2) after cooling, washing, drying after contacting completion.The amorphous zirconium hydroxide of the present application has very high water absorption rate, water absorption rate is 110~130%, after calcination at 550 DEG C for 3 hours, it has specific surface area 30~60m 2 / g, total pore volume 0.16~0.25cm 3 / g, average pore size 10~30nm.After calcination at 650 DEG C for 3 hours, it has specific surface area 30~50m 2 / g, total pore volume 0.16~0.21cm 3 / g, average pore size 20~30nm.The amorphous zirconium hydroxide of the present application is used as carrier to prepare n-butane isomerization catalyst, and has better activity.

Claims

1. An amorphous zirconium hydroxide, characterized in that, The amorphous zirconium hydroxide has a water absorption rate of 95%–130% and a specific surface area of ​​300–350 m². 2 / g, total pore volume is 0.32~0.60 cm³. 3 / g, with an average pore size of 4~6nm.

2. The amorphous zirconium hydroxide according to claim 1, wherein, The physicochemical parameters of amorphous zirconium hydroxide include: After being calcined at 550℃ for 3 hours, it has a specific surface area of ​​30~60 m². 2 / g, total pore volume is 0.16~0.25 cm³ 3 / g, with an average pore size of 10~30nm; After being calcined at 650℃ for 3 hours, it has a specific surface area of ​​30~50 m². 2 / g, total pore volume is 0.16~0.21 cm³ 3 / g, with an average pore size of 20~30nm.

3. A method for preparing amorphous zirconium hydroxide as described in claim 1 or 2, characterized in that, The method includes: ① In the presence of additives, an alkaline hydroxide aqueous solution and a zirconium salt aqueous solution are added dropwise and mixed to form a precipitate while stirring. ②After the solution is added, heat the solution and maintain a constant temperature of 70℃~100℃; ③After completion, cool and wash; ④ Drying; The additive is selected from one or more of acetic acid, ammonium acetate, sulfuric acid, ammonium sulfate, oxalic acid, ammonium oxalate, and citric acid; The alkaline hydroxide is ammonia and / or sodium hydroxide; The zirconium salt is zirconium oxychloride and / or zirconium nitrate; The mass ratio of additive to zirconium salt is 1~100:100; The molar ratio of Zr ions to hydroxide ions is 1:2 to 1:4.5; The mass ratio of zirconium salt to alkaline substance is 1-50; In aqueous solution, the concentration of zirconium salt is 10-50 wt%; The mixing conditions include a time period of 6 to 24 hours; The stirring speed is 150 rpm to 300 rpm.

4. The method according to claim 3, wherein, The additive is selected from one or more of acetic acid, ammonium acetate, sulfuric acid, and ammonium sulfate.

5. The method according to claim 4, wherein, The additive is selected from at least two of acetic acid, ammonium acetate, sulfuric acid, and ammonium sulfate.

6. The method according to claim 5, wherein, The additive is a mixture of acetic acid and ammonium acetate.

7. The method according to claim 6, wherein, The mass ratio of acetic acid to ammonium acetate is 0.4-0.6:

1.

8. The method according to claim 3, wherein, Cool to below 35°C and wash with water and / or acid; and / or Drying conditions include: 110℃~120℃.

9. The method according to claim 3, wherein, The mass ratio of additive to zirconium salt is 10~40:100; and / or The mass ratio of zirconium salt to alkali is 2-25; and / or In aqueous solution, the concentration of zirconium salt is 25-45 wt%.

10. The method according to claim 3, wherein, Step ② Maintain constant temperature for 6-24 hours; and / or The concentration of the alkaline hydroxide aqueous solution is 5wt%~25wt%; and / or The concentration of zirconium salt in the aqueous solution is 10-50 wt%; and / or The mass ratio of additive to zirconium salt is 0.01-1; and / or The mass ratio of zirconium salt to alkali is 1-50; and / or After step ③, cool to below 35°C and wash with water; and / or Step ④ drying conditions include: 110℃~120℃; and / or The stirring speed is 150 rpm to 300 rpm.

11. The method according to claim 10, wherein, The concentration of zirconium salt in the aqueous solution is 25-45 wt%; and / or The mass ratio of additives to zirconium salt is 0.1-0.4; and / or The mass ratio of zirconium salt to alkaline substance is 2-25.

12. The method according to claim 3, wherein, The method includes: ① Add ammonia water dropwise to an aqueous solution of zirconium oxychloride containing acid and / or acid salts to form a precipitate while stirring. ②After the solution is added, heat to 70℃~100℃ and keep at a constant temperature for 6~24 hours; ③ After completion, cool to below 35°C, filter the precipitated zirconium hydroxide and wash with water; ④ Dry the zirconium hydroxide at 110℃~120℃.

13. The method according to claim 12, wherein, The concentration of zirconium oxychloride in the aqueous solution is 10-50 wt%; and / or The mass ratio of additive acid and / or acid salt to zirconium oxychloride is 0.01-1; and / or The mass ratio of zirconium oxychloride to ammonia is 1-50; and / or Step ① The concentration of ammonia water is 5wt%~25wt%; and / or Step ① The ratio of zirconium oxychloride to ammonia is 1:2 to 1:4.

5.

14. The method according to claim 13, wherein, The concentration of zirconium oxychloride in the aqueous solution is 25-45 wt%; and / or The mass ratio of additive acids and / or acid salts to zirconium oxychloride is 0.1-0.4; and / or The mass ratio of zirconium oxychloride to ammonia is 2-25.

15. The use of the amorphous zirconium hydroxide as described in claim 1 or 2 as a catalyst support.

16. The application of the amorphous zirconium hydroxide as described in claim 1 or 2 as a support for the preparation of n-butane isomerization catalysts.

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