Gravity Separation & Concentration Methods

Gravity Separation & Concentration Methods

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Simplest Aluminum Separation From Sodium Aluminate (No replies)

B James
3 years ago
B James 3 years ago

Warning: I am no chemist, so excuse me if I seem green.


How I ended up with Sodium Aluminate:

This is a by product from dissolving cast aluminum with sodium hydroxide mixed with hotter and heated.

I do this in very small batches. 55 gallon drums. Then I store the now, sodium aluminate in totes.

After I dissolve so much aluminum, the sodium hydroxide becomes saturated with aluminum (sodium aluminate) which stops me from being able to dissolve any more aluminum. Then I have to make a new batch.

I currently send the sodium aluminate off to a sodium aluminate manufacturer that can turn it into new product.


What I am trying to accomplish:

I want to be able to continue to reuse my sodium hydroxide for dissolving more aluminum.

By removing most of the aluminum, I feel that I could use the sodium hydroxide as well as all of the water and just recycle any aluminum that I precipitate.


My current idea and understanding:

If you are familiar with the bayer process. The bayer process has a stage in it that I am trying to accomplish on a small level (55 gallon drum at a time)


Basic Bayer process: From what I understand

1.This is the process where they take baxite ore

2.Mix it with sodium hydroxide,

3.Which dissolves the bits of alumina which makes sodium aluminate

4.Then the precipitate the alumina which falls to the bottom

5.Then they are able to reuse the sodium hydroxide


Point 4 and 5 are exactly what I am trying to figure out on a small scale. (55gal batches)


So, what do they use to seed the sodium aluminate, to get the alumina to precipitate to the bottom of the tank?

A chemist suggested I used a,

non-activated alumina tri-hydrate powder

He used to work at Alcoa


I have attempted a small lab test and havent been able to figure it out.

I took my sodium aluminate and chilled it then blended it in a small batch with ice and just never saw it precipitate


I have tried using Huber- Spacerite S11 as the floc


I have a feeling I just need better conditions for this test to make this work.


Im open to suggestions/products and any input.

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