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Name: Shawn J.
Status: student
Age: 17
Location: N/A
Country: N/A
Date: 2000


Question:
I read in someone elses question that they were trying to get aluminum powder. They said they put aluminum foil in HCl and then used electrolysis to get it by itself. When you use electrolysis on salt water you end up with NaOH. Shouldn't the electrolysis of of aqueous aluminum chloride produce Al(OH)3 and release hydrogen and chlorine? I am confused. Please tell me what is made and show me the chemical equation.


Replies:
Depending on quantity needed and how fine a "screen" you need, preparation might be relatively easy. Coarser screens can be prepared by filing the edge from a block of aluminum stock (okay, so these are filings, technically speaking, but easy to prepare in small quantity.)

Do NOT use a grinder to prepare aluminum powder - this will quickly kill the wheel by "loading it up" The wheel can be redressed with a dressing tool, but the costs in time and equipment are not justified by the output. Sodium metal may be prepared by electrolysis of molten NaCl, also releasing chlorine gas, likewise recovered for use. Similarly, molten AlCl3 may be electrolysed to Al and Cl2, but unlike NaCl that melts higher than Na, Al melts higher than AlCl3, so (solid) Al should form at the cathode in this cell. [2 AlCl3 -emf-> 2Al + 3Cl2] But not necessarily as a powder. If you need a better grade of Al powder than filings, buy it from a chemical supply company.

Tim Spry



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