Iron oxide red for lithium iron phosphate cathode material as well as preparation method and application thereof

Abstract

The invention discloses iron oxide red for a lithium iron phosphate cathode material as well as a preparation method and application of the iron oxide red. The preparation method comprises the following steps: (1) dissolving waste solid ferrous sulfate of a titanium dioxide factory in water, adding an inorganic polymer flocculant, and standing to obtain a ferrous sulfate clarified solution; (2) adding the ferrous sulfate clarified solution into an oxidation barrel, adding a water-soluble acrylic polymer modifier and a dispersing agent, uniformly stirring, adding liquid caustic soda to quicklyadjust the pH value of the solution to 11.0-14.0, and continuing an oxidation reaction to prepare a brownish red seed crystal, and (3) carrying out an oxidation reaction on the obtained seed crystal to obtain the iron oxide red for the lithium iron phosphate positive electrode material. The iron oxide red is produced by adopting a pure liquid phase method, and the prepared iron oxide red is non-toxic, environment-friendly, advanced in powder fineness, low in heavy metal content, good in flame retardance and high in purity. Compared with the iron oxide red produced by a traditional method, theiron oxide red produced by the method has great advantages in the aspects of preparation process, product purity and particle size.

Description

technical field

[0001] The invention belongs to the field of battery positive electrode materials, and relates to a preparation method of iron oxide red, in particular to an iron oxide red for lithium iron phosphate positive electrode material and its preparation method and application. Background technique

[0002] Iron oxide red, also known as iron red and iron oxide red, is the most widely used color inorganic pigment in the world. Its chemical formula is Fe 2 o 3 . Iron oxide red has excellent properties such as light resistance, high temperature resistance, alkali resistance and atmospheric influence resistance. The raw materials are simple and easy to obtain, and can make full use of waste and by-product resources in other industries. It has low toxicity and a wide range of uses. It is widely used in construction, rubber, industries such as plastics and coatings. Due to the continuous consumption of irreplaceable energy sources and imminent environmental problems, h...

Examples

Embodiment 1

[0036] (1) Stir and dissolve the waste solid ferrous sulfate (ferrous sulfate content is 80wt%) in water from the titanium dioxide factory, the dissolution temperature is 60°C, the concentration is 0.5g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.01wt%, remove impurity precipitation after standing for 12h, obtain upper layer ferrous sulfate clarified solution;

[0037] (2) Add the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation barrel, add the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 1% and carry out high-speed stirring after adding the mass fraction 30min, the reaction temperature is 70°C. Then add a certain amount of liquid caustic soda with a mass concentration of 30% to quickly adjust the pH value of the solution to 11.0, and continue the oxidation reaction for 4 hours to obtain brownish-red seed crystals, which remain within the range of ...

Embodiment 2

[0044] (1) Stir and dissolve the waste solid ferrous sulfate (ferrous sulfate content is 80wt%) in water in the titanium dioxide factory, the dissolution temperature is 70°C, the concentration is 0.75g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.02wt%, remove impurity precipitation after standing for 18h, obtain upper layer ferrous sulfate clarified solution;

[0045](2) adding the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation tank, adding the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 2% and carrying out high-speed stirring after adding the mass fraction 45min, the reaction temperature is 80°C. Then add a certain amount of liquid caustic soda with a mass concentration of 32% to quickly adjust the pH value of the solution to 12.5, and continue the oxidation reaction for 6 hours to obtain brownish-red seed crystals, which remain within the rang...

Embodiment 3

[0053] (1) Stir and dissolve the waste solid ferrous sulfate (the content of ferrous sulfate is 80wt%) of the titanium dioxide factory in water, the dissolution temperature is 80°C, the concentration is 1.0g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.03wt%, remove impurity precipitation after standing for 24h, obtain upper layer ferrous sulfate clarified solution;

[0054] (2) adding the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation tank, adding the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 3% and stirring at a high speed 60min, the reaction temperature is 90°C. Then add a certain amount of liquid caustic soda with a mass concentration of 32% to quickly adjust the pH value of the solution to 14.0, and continue the oxidation reaction for 8 hours to obtain brownish-red seed crystals, which remain within the range of 7.0 within 1 hour. ;

[0...

technical field

[0001] The invention belongs to the field of battery positive electrode materials, and relates to a preparation method of iron oxide red, in particular to an iron oxide red for lithium iron phosphate positive electrode material and its preparation method and application. Background technique

[0002] Iron oxide red, also known as iron red and iron oxide red, is the most widely used color inorganic pigment in the world. Its chemical formula is Fe 2 o 3 . Iron oxide red has excellent properties such as light resistance, high temperature resistance, alkali resistance and atmospheric influence resistance. The raw materials are simple and easy to obtain, and can make full use of waste and by-product resources in other industries. It has low toxicity and a wide range of uses. It is widely used in construction, rubber, industries such as plastics and coatings. Due to the continuous consumption of irreplaceable energy sources and imminent environmental problems, h...

Examples

Embodiment 1

[0036] (1) Stir and dissolve the waste solid ferrous sulfate (ferrous sulfate content is 80wt%) in water from the titanium dioxide factory, the dissolution temperature is 60°C, the concentration is 0.5g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.01wt%, remove impurity precipitation after standing for 12h, obtain upper layer ferrous sulfate clarified solution;

[0037] (2) Add the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation barrel, add the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 1% and carry out high-speed stirring after adding the mass fraction 30min, the reaction temperature is 70°C. Then add a certain amount of liquid caustic soda with a mass concentration of 30% to quickly adjust the pH value of the solution to 11.0, and continue the oxidation reaction for 4 hours to obtain brownish-red seed crystals, which remain within the range of ...

Embodiment 2

[0044] (1) Stir and dissolve the waste solid ferrous sulfate (ferrous sulfate content is 80wt%) in water in the titanium dioxide factory, the dissolution temperature is 70°C, the concentration is 0.75g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.02wt%, remove impurity precipitation after standing for 18h, obtain upper layer ferrous sulfate clarified solution;

[0045](2) adding the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation tank, adding the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 2% and carrying out high-speed stirring after adding the mass fraction 45min, the reaction temperature is 80°C. Then add a certain amount of liquid caustic soda with a mass concentration of 32% to quickly adjust the pH value of the solution to 12.5, and continue the oxidation reaction for 6 hours to obtain brownish-red seed crystals, which remain within the rang...

Embodiment 3

[0053] (1) Stir and dissolve the waste solid ferrous sulfate (the content of ferrous sulfate is 80wt%) of the titanium dioxide factory in water, the dissolution temperature is 80°C, the concentration is 1.0g / L, and the inorganic polymer flocculant is added Polymerized ferric sulfate 0.03wt%, remove impurity precipitation after standing for 24h, obtain upper layer ferrous sulfate clarified solution;

[0054] (2) adding the clarified solution of ferrous sulfate in the upper layer in the step (1) into the oxidation tank, adding the water-soluble acrylic polymer modifier and the dispersant propylene glycol with a mass fraction of 3% and stirring at a high speed 60min, the reaction temperature is 90°C. Then add a certain amount of liquid caustic soda with a mass concentration of 32% to quickly adjust the pH value of the solution to 14.0, and continue the oxidation reaction for 8 hours to obtain brownish-red seed crystals, which remain within the range of 7.0 within 1 hour. ;

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