Method for cleanly preparing vanadium oxides

Abstract

The invention discloses a method for cleanly preparing vanadium oxides, comprising the following steps of: with vanadate as a raw material and reducible gases as reducing agents, making the vanadate react with the reducible gases at the temperature of 300-1500 DEG C for 0.5-8h to obtain low-valent vanadate and a byproduct of NaOH; cooling and then washing a reaction mixer with water; hydrolyzing the washed product at the temperature of 20-200 DEG C for 0-6h; and filtering the hydrolysate and then drying the hydrolysate at the temperature of 80-300 DEG C for 0-24h to obtain vanadium oxides (V2O5, V2O3 and VO2) and a byproduct of vanadium-containing alkaline solution for cycle use. Meanwhile, the preparation of the vanadium oxides and the discharge of non-polluted products are realized and the problems of the vanadium and high-ammonium contained wastewater and the like in the industrial production method are solved. The vanadium acid and alkali salts comprise metavanadate, ortho-vanadate and pyrovandate which are respectively sodium metavanadate or potassium metavanadate, sodium orthovanadate or potassium orthovanadate and sodium pyrovanadate or potassium pyrovanadate; and the reducing gases include hydrogen gas, natural gas, ammonia gas, coal gas or a mixer of the hydrogen gas, the natural gas, the ammonia gas and the coal gas.

Description

technical field

[0001] The present invention relates to a vanadium oxide (V 2 o 5 , V 2 o 3 、VO 2 ) preparation method, specifically the clean preparation method of low-temperature reduction of vanadate vanadium oxide by gas reducing agent Background technique

[0002] Vanadium oxide is mainly used in the metallurgy, electronics, chemical and petroleum industries such as the production of alloys, colorants in the glass and ceramic industries, sulfuric acid and catalysts for petrochemical production.

[0003] Vanadium oxides include vanadium pentoxide (V 2 o 5 ), vanadium trioxide (V 2 o 3 ) and vanadium dioxide (VO 2 ), etc., different oxide production methods vary. for V 2 o 5 According to different minerals, there are mainly alkali method, acid method and chlorination roasting method. Alkali method is to obtain sodium metavanadate by roasting vanadium ore with soda ash. US4039582 uses sodium metavanadate solution to precipitate ammonium chloride or ammonium su...

Examples

Embodiment 1

[0014] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 500°C, the reduction time was 5 hours, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0015] The reduced product was washed with cold water after cooling, the washed product was hydrolyzed at 80°C for 3 hours, and the hydrolyzed product was filtered and dried at 100°C for 12 hours to obtain V 2 o 5 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0016] at V 2 o 5 sample, V 2 o 5 The main content is greater than 98.0%, and the Na content is less than 0.5%.

Embodiment 2

[0018] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 600°C, the reduction time was 4h, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0019] The reduced product was washed with cold water after cooling, and the washed product was hydrolyzed under pressure at 120°C for 3 hours under nitrogen atmosphere, and the hydrolyzed product was filtered and dried at 150°C for 6 hours to obtain VO 2 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0020] in VO 2 In the sample, VO 2 The main content is greater than 98.0%, and the Na content is less than 0.5%.

Embodiment 3

[0022] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 700°C, the reduction time was 3h, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0023] The reduced product was washed with cold water after cooling, and the washed product was hydrolyzed under pressure at 150°C for 3 hours under a protective atmosphere, and the hydrolyzed product was filtered and dried at 150°C for 6 hours to obtain V 2 o 3 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0024] at V 2 o 3 sample, V 2 o 3 The main content is greater than 99.0%, and the Na content is less than 0.5%.

technical field

[0001] The present invention relates to a vanadium oxide (V 2 o 5 , V 2 o 3 、VO 2 ) preparation method, specifically the clean preparation method of low-temperature reduction of vanadate vanadium oxide by gas reducing agent Background technique

[0002] Vanadium oxide is mainly used in the metallurgy, electronics, chemical and petroleum industries such as the production of alloys, colorants in the glass and ceramic industries, sulfuric acid and catalysts for petrochemical production.

[0003] Vanadium oxides include vanadium pentoxide (V 2 o 5 ), vanadium trioxide (V 2 o 3 ) and vanadium dioxide (VO 2 ), etc., different oxide production methods vary. for V 2 o 5 According to different minerals, there are mainly alkali method, acid method and chlorination roasting method. Alkali method is to obtain sodium metavanadate by roasting vanadium ore with soda ash. US4039582 uses sodium metavanadate solution to precipitate ammonium chloride or ammonium su...

Examples

Embodiment 1

[0014] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 500°C, the reduction time was 5 hours, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0015] The reduced product was washed with cold water after cooling, the washed product was hydrolyzed at 80°C for 3 hours, and the hydrolyzed product was filtered and dried at 100°C for 12 hours to obtain V 2 o 5 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0016] at V 2 o 5 sample, V 2 o 5 The main content is greater than 98.0%, and the Na content is less than 0.5%.

Embodiment 2

[0018] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 600°C, the reduction time was 4h, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0019] The reduced product was washed with cold water after cooling, and the washed product was hydrolyzed under pressure at 120°C for 3 hours under nitrogen atmosphere, and the hydrolyzed product was filtered and dried at 150°C for 6 hours to obtain VO 2 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0020] in VO 2 In the sample, VO 2 The main content is greater than 98.0%, and the Na content is less than 0.5%.

Embodiment 3

[0022] The reduction of 1000g of sodium metavanadate was carried out in a box-type reduction furnace, using hydrogen as the reducing gas, the reduction temperature was 700°C, the reduction time was 3h, and the hydrogen flow rate during the reduction process was 0.6L / min.

[0023] The reduced product was washed with cold water after cooling, and the washed product was hydrolyzed under pressure at 150°C for 3 hours under a protective atmosphere, and the hydrolyzed product was filtered and dried at 150°C for 6 hours to obtain V 2 o 3 ; The by-product of washing and hydrolysis is a vanadium-containing NaOH solution, which is recycled.

[0024] at V 2 o 3 sample, V 2 o 3 The main content is greater than 99.0%, and the Na content is less than 0.5%.