Expert: Dr. Henry Boyter, Jr. - 6/2/2005

Question
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Followup To
Question -  
Sir,

I am jewleller engaged in refining of gold in my small coal kiln.  After I do refine gold from kiln, we have to put liquidate gold in a metal pattern and sinks it in water.  This waster is being mixed for an acid as well.

The water we store in a bucket contains small bubbles on sides as well as in middle. These bubble are caused by air pockets in that water.

When I put gold in this bubbled/air pocketed water the quality of gold refining is disturbed.  

I wish to know how can these bubbles be removed to get better refined gold.


Waheed Butt

Answer -
Try boiling the water and then let it cool in the same container or transfer with minimal poring.  You mention a bucket, try different materials


Sir,

Problem is water cannot be boiled as some nitric acid is mixed into it to get gold purified after drawing it from kiln

Answer
Boil it before you add the nitric.  Stirring the nitric may put the air right back in so do it slowly, but unless you want to go to a vacuum system, that's about all you can do.

If it is only the oxygen in the water that is the problem, not really the bubbles, you could bubble nitrogen gas through the water.  That would reduce the oxygen level.  The nitrogen will be inert.