Method for separating iron and aluminum from red mud and/or iron-containing solid waste

[0068] The process of separating aluminum and iron by acidolysis and fractional precipitation of red mud includes the following steps:

[0069] (1) React 1kg of red mud and 4kg of 50wt% sulfuric acid at 170°C for 10h to obtain a slurry;

[0070] (2) the slurry is separated to obtain 0.3kg of reaction residue (first product) and acidic solution;

[0071] (3) Add 200g of reduced iron powder to the acidic solution, the reaction is complete at 50°C, and the yellow solution turns into a green solution;

[0072] (4) Add 10wt% ammonia aqueous solution dropwise in the solution, control the pH value at 4.5, obtain a colloidal slurry containing off-white, after centrifugation, obtain the corresponding colloidal precipitation and transparent solution;

[0073] (5) After the colloid precipitation obtained in step (4) is dried and calcined, 0.4kg of the second product is obtained;

[0074] (6) Add ammonia solution dropwise to the transparent solution obtained by separation in step (4), a...

[0085] The process of separating aluminum and iron by acidolysis and fractional precipitation of red mud includes the following steps:

[0086] (1) 1kg of red mud, 3kg of 80wt% sulfuric acid and 1kg of paraformaldehyde were reacted at 70°C for 12h to obtain a slurry;

[0087] (2) separating the slurry to obtain a reaction residue (first product) and an acidic solution;

[0088] (3) Add dropwise 10wt% sodium hydroxide aqueous solution in the solution, control the pH value at 4.5, obtain the off-white colloidal slurry, after centrifugation, obtain the corresponding colloidal precipitation and transparent solution;

[0089] Steps (4), (5) and (6) are the same as steps (5), (6) and (7) in Example 1 in turn.

[0090] The masses of the first product, the second product and the third product obtained in this example were 0.4kg, 0.3kg and 0.3kg respectively.

[0091] The composition of red mud and each product is as shown in Table 2 in this embodiment:

[0092] Table 2 Composition ...

[0105] The process of separating aluminum and iron by acidolysis and fractional precipitation of red mud includes the following steps:

[0106] (1) React 1kg of red mud and 3kg of 30wt% hydrochloric acid at 130°C for 12h to obtain a slurry;

[0107] (2) Slurry is separated to obtain 0.3kg of reaction residue (first product) and acidic solution;

[0108] (3) Add 0.2kg of aluminum powder to the acidic solution, and the reaction is complete at 30°C, changing from a yellow solution to a green solution;

[0109] (4) Add dropwise 10wt% potassium hydroxide aqueous solution in the solution, control the pH value at 4.5, obtain the off-white colloidal slurry, after centrifugation, obtain the corresponding colloidal precipitation and transparent solution;

[0110] Steps (5), (6) and (7) are sequentially the same as steps (5), (6) and (7) in Example 1.

[0111] The masses of the first product, the second product and the third product obtained in this example were 0.3kg, 0.6kg and 0.4kg ...