Make Aluminium Hydroxide (fail)

+Perry Gershin Next time use ammonia solution instead of sodium bicarbonate. That´s how I made mine and it´s a really clean and better method.

I’ve used 20-25% sodium hydroxide solution to remove smeared aluminum from dremel burrs and it works great. I also use a 3-4% sodium hydroxide solution to strip anodizing off aluminum quite effectively. In the diluted alkali, I noticed a white deposit on the bottom. Perhaps this was the stripped anodize settling as aluminum hydroxide. FYI, most dyes remain in the alkaline solution. What I propose is to dissolve aluminum in 20-25% sodium hydroxide. Extreme caution is advised as this could in fact be an energetic reaction with alkaline solution possibly overflowing containers if precautions not followed. When a clear concentrate is obtained, dilute with 8 to 10 times by volume with water. Aluminum hydroxide should crash out since sodium aluminate is unstable in dilute solutions.

First! Really enjoyed your potash videos. Really helped clear up some things for me. Thank you!

I think I have an idea how could you purify it. React it with a weak acid that will react only with the carbonate (presumably it is leftover sodium carbonate left in soaked up water that precipitated out when drying). For example do some acetic acid washings until no more visible bubbling occurs, wash it with distilled water and it should be quite pure.

I suspect what you have made is basic aluminum carbonate Al(OH)CO3

Hi i want to make aluminum hydroxide from bauxite ore and react with sodium hydroxide kindly guide me how can i Precipetate aluminum hydroxide from it

I prefer making first an ammonia complex of the metal, and only than adding sodium hydroxide. At least in case of copper(II) hydroxide, it made a lot purer product than just dumping in base. I'm not sure what would it look like with Al(OH)3, but I think it would look simmilar.

What are the necessary materials and method for aluminum sulfate?

PERRY.................When i wash an insoluble hydroxide...because they clog up a filter so easily and trap in water so easily...if i made a small amount like you did i would put it in like a half gallon or gallon vessel (like the size you would make lemon aid or kool aid in) and fill with water and stir it good then put plastic wrap over the top and let it sit until all or most of the hydroxide settle to the ground. Then pour most of the water off without pouring out the hydroxide and then fill the container back up with water and stir and cover with plastic and keep repeating until you do it 6 or 7 times and then after you pour off most of the water the last time just put it in a filter and wash with a little water and suck the cake dry with vacuum and then IF IT STILL HAS CARBONATE IN IT then the reason why is that you are also making something called "basic aluminum carbonate" Al(HCO3)(CO3). And if that is the case which i think it is. Then you should try using a hydroxide instead of a carbonate. Maybe like sodium hydroxide or ammonium hydroxide.

Dunno exactly what went wrong here, but I am thinking why not from sodium aluminate then react with hydrochloric acid to get sodium chloride and aluminium hydroxide?

Adding sodium was not a great way to react the aluminium as you can easily complex it and get a mixture of sodium aluminate with various sodium aluminate carbonates unless the two were in a somewhat exact perfect mixture. I suppose your Alum was hydrated meaning you used way too little compared to pure anhydrous. Try to heat the alum to see if it looses water.