Ammonium aluminum sulfate is colorless transparent crystal or white powder. Slightly soluble in water, dilute acid and glycerol, and the aqueous solution is acidic. It is insoluble in alcohol. It usually exists in the form of 12 kinds of crystal water. It tastes a little sweet and astringent. 10 loses molecular crystal water at 20℃, becomes anhydrous at about 250℃, decomposes above 280℃, and 1g is dissolved in 7 ml of water and 0.5 ml of boiling water.

Ammonium aluminum sulfate is soluble in glycerol and almost insoluble in ethanol. The aqueous solution is acidic to litmus. The pH of 0.05mol/L solution is 4.6. Relative density 1.64. Refractive index 1.459.

Potassium aluminum sulfate dodecahydrate, also known as alum, alum, potassium alum, potassium aluminum alum and potassium alum, has been prohibited from being used in food additives by the state. It is a compound of potassium sulfate and aluminum sulfate containing crystal water. Colorless cubic crystal, often octahedral in appearance, or cubic, rhombic dodecahedron forms a polygon, belonging to α -type alum double salt, with glass luster.

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Disposal and storage of ammonium aluminum sulfate;

Precautions for operation: closed operation, local exhaust. Operators must be specially trained and strictly abide by the operating procedures. Operators are advised to wear self-priming filter dust mask, chemical safety glasses, anti-gas infiltration overalls and rubber gloves. Avoid dust. Avoid contact with oxidants. Light loading and unloading to prevent packaging damage. Equipped with leakage emergency treatment equipment. Empty containers may retain harmful substances.

Precautions for storage: Store in a cool and ventilated warehouse. Stay away from fire and heat sources. Should be stored separately from oxidant, and should not be mixed. The storage area should be equipped with suitable materials to contain leakage.

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