Sciencemadness Discussion Board - Purifying molten aluminum from soda cans?

Purifying molten aluminum from soda cans?

nikotyna1939 - 1-1-2026 at 04:02

What is the easiest ways to purify molten aluminum from soda cans at backyard foundry?
By the way sorry for the previous posts I want primarily to remove the manganese metal from the molten aluminum can which i read online is the main contaminant in the molten aluminum from soda cans.

[Edited on 1-1-2026 by nikotyna1939]

Sulaiman - 1-1-2026 at 04:50

can you determine the manganese concentration before and after any processing ?

if not then what is the purpose ?

metalresearcher - 1-1-2026 at 10:19

What do you mean with 'purify' ? It can be remove the dross (can be done with NaOH prills which melt and dissolve the Al2O3 dross) or purify the Al metal itself. Mostly the beverage can Al us alloyed with a bit of Cu and maybe Mn.

bnull - 1-1-2026 at 15:33

Manganese forms intermetallic compounds with aluminum and iron. Some, if not all, of them are solid and can be filtered out, leaving molten aluminum.

What is the intended use of the purified aluminum? If it doesn't require a good structural strength, then you can use the alloy as it was originally.

macckone - 10-1-2026 at 11:28

If you need pure aluminum, buy it. If you are recycling cans, the primary contaminant is carbon from the lining. Various fluxes can have differing impacts. Zinc chloride and ammonium chloride are common ones. Zinc tends to make aluminum alloys less brittle. Carbon and hydrogen make it more brittle. Manganese makes aluminum less reactive. While magnesium makes it more reactive but stronger in tensile strength.

upgrading the alloy grade into 7178 aluminum alloy

nikotyna1939 - 14-1-2026 at 21:26

I'm planning to purify the aluminum soda cans which are made from grade 3004 & 5182 into 7178 aluminum alloy grade for making high quality timing pulley

the main element that i want to remove

nikotyna1939 - 14-1-2026 at 21:28

the main element that i want to remove is manganese
because i read aluminum from soda cans contains high in manganese metal

the reasons of using aluminium from soda cans

nikotyna1939 - 14-1-2026 at 23:36

i want to make from soda cans because i have 500 kg of scrap soda can aluminum
the price is RP 18 000 PER KG while the cost of timing pulley is Rp 60 000 PER PCS
WHICH PER PCS OF TIMING PULLEY PRICE IS 3X MORE EXPENSIVE THAN PER KG OF 1KG OF SCRAP ALUMINUM CANS WHILE THE WEIGHT OF 1 PCS TIMING PULLEY IS 56.5 GRAMS WHICH 1 KG OF SCRAP ALUMINUM CAN PRODUCE ABOUT 17 PIECE OF PULLEY

[Edited on 15-1-2026 by nikotyna1939]

Sulaiman - 15-1-2026 at 04:33

amongst the reasons that manganese is added to aluminium are :
hardness, strength and corrosion resistance
ideal for making pulleys etc.
and
a quick google pointed to at least one 7178 alloy that contains 0.3% Mn

Texium - 15-1-2026 at 09:02

Quote: Originally posted by nikotyna1939

i want to make from soda cans because i have 500 kg of scrap soda can aluminum
the price is RP 18 000 PER KG while the cost of timing pulley is Rp 60 000 PER PCS
WHICH PER PCS OF TIMING PULLEY PRICE IS 3X MORE EXPENSIVE THAN PER KG OF 1KG OF SCRAP ALUMINUM CANS WHILE THE WEIGHT OF 1 PCS TIMING PULLEY IS 56.5 GRAMS WHICH 1 KG OF SCRAP ALUMINUM CAN PRODUCE ABOUT 17 PIECE OF PULLEY

How about you settle down on the all caps and think about this for a second: even if you could purify the aluminum, how are you going to turn it into timing pulleys? You can’t just cast them in a mold, they need to be precision machined. That’s the main reason they’re a lot more expensive than the value of the metal they’re made of. Do you have the means to machine these pieces? I’m guessing not given that your post history is essentially one poorly planned way to make money after another…

bnull - 15-1-2026 at 17:27

Half a ton of aluminum? I'd try to haggle it up or exchange it for stuff at the junkyard.

If you can (1) melt and standardize the metal, (2) find someone with expertise and a machine to make the pulleys, and (3) find buyers for them, then you'll make a lot of money. But (1) is it easy to melt and standardize half a tone of aluminum at home? No, and you will spend quite a lot of money on that. (2) How much will the lathe guy charge you to make almost half a ton of pulleys? A considerable amount which you're probably going to have to pay beforehand because the guy is not stupid, he is not running a philanthropic shop, and customers whose projects offer better chances of generating money have precedence. (3) Who is going to buy homemade timing pulleys? No serious buyer, not even yours truly. If I needed one, I'd go after a commercial product, something that had been made according to industrial regulations or whatever they are called.

You need to study how much a process will cost and how much work needs to be done so as to transform discarded stuff into valuable stuff.

Sulaiman - 15-1-2026 at 19:29

IF you think that going into the industrial production world is a good path for you then this could be a good start,
if it is just a one time thing then I think that the initial investments required will stress you
and there is the potential for living with 500 kg of pulleys - for many years.
If you already have potential customers then maybe it is worth the risk ?
a good mold will significantly reduce machining time,
drilling and tapping also take time.
I'm not a business person so my comments here are just for your consideration.
(just an old guy sitting in an armchair far far away)
guessing at one minute per pulley, about 500 hours of work.

I've only melted and cast 100's grammes of Al cans
I have lately been melting and casting kilogrammes of recycled lead,
neither cast perfectly for me (I am a complete noob)
even though I watched many YT videos

I got fewer voids last time - but I still got voids.

Personally I'd just melt it and make ingots for sale - because I'm a lazy guy.

reducing the manganese content

nikotyna1939 - 16-1-2026 at 18:09

I'm asking this question for mainly reducing the manganese content into 7178 grade alloy aluminum percentage range

THE Range of aluminium metal i possessed and THE MOTIVES NOT JUST BUY A NEW PULLEY

nikotyna1939 - 16-1-2026 at 18:23

I CURRENTLY possessed about 100 to 500 kg of aluminum i thought i will get a extra bonus for example 1 kg scrap aluminum price in my location is RP 18000 PER KG CURRENTLY,
THE WEIGHT OF PULLEY IS 56.5 GRAMS
THE PRICE OF 1 GRAMS OF ALUMINUM METALS IS RP 18
BUT IF I CALCULATE THE RAW MATERIAL BUDGET IS 56.5 x 18 = RP 1017
I CAN SELL IT ALMOST 90 TO 100 X OT TIMES MORE EXPENSIVE
PLUS I WANT TO BE A SMALL SCALE MANUFACTURER

[Edited on 17-1-2026 by nikotyna1939]

former foundry vacant factory lots

nikotyna1939 - 16-1-2026 at 18:30

currently my parents owns a vacant factory lot which is used as former foundry near at my home about 1000 m2 area size
i thought i can use it as small scale factory plus there are a lathe machine and foundry furnace still inside it and I'm planning to bought the equipment from the former tenant

[Edited on 17-1-2026 by nikotyna1939]

reasons of asking this question

nikotyna1939 - 16-1-2026 at 18:39

i asked this question because wanted what is the easiest way to upgrade it into 7178 alloy at home first
after i had the confidence i will buy the former foundry equipment from the former tenant

[Edited on 17-1-2026 by nikotyna1939]

so what is the easiest method to upgrade into 7178 grade alloy

nikotyna1939 - 16-1-2026 at 18:42

what is the easiest method to upgrade into 7178 grade alloy at home first

bnull - 17-1-2026 at 06:33

Do you have any means to test the purity of the alloy? I think the answer is no, but I have been wrong before and might be wrong now.

If the answer to question above is yes: do you have any experience with metallurgy? The answer is probably no, unless we stretch the definition of metallurgy to include "occasionally melting a few bits of metal through the years," which I believe is the case.

If the answer to the question above is yes: are you willing to spend a considerable amount of money in the project? Again, the answer is most certainly no. You need to spend money in order to make money, from learning courses to medical and chemical supplies.

You want to recycle and turn discarded stuff into useful material? That's good, everyone should do it one way or another. But you must understand what things you are able to do and what things you are not able to do under the current circumstances. Remember your post about recycling non-dairy creamer that was being discarded by an ice cream shop near your home (https://www.sciencemadness.org/whisper/viewthread.php?tid=16...)? Remember the calculations I made? Well, that's it. You need the knowledge and the calculations to make sure a project is feasible.

Edit: Study this book: Quantitative Chemical Analysis, by Hamilton and Simpson. It will get you somewhere, as long as you are willing to take time and actually study it.

[Edited on 17-1-2026 by bnull]

The necessity of a portable Handheld X-Ray Fluorescence (XRF) Spectrometry?

nikotyna1939 - 17-1-2026 at 21:47

Is it necessary to buy a portable Handheld X-Ray Fluorescence (XRF) Spectrometry for a medium-scale foundry?
I was wondering about it because the former foundry lot that is near my home was a medium-scale operation for cheap aluminum kitchen utensil production.

macckone - 19-1-2026 at 07:26

If you want precision alloy, yes you need an xfr. If you want cheap pulleys you can sell for profit, then don't worry about exact composition. The main impurity is carbon from can lining. The way a commercial operation improves metals from recycling is dilution. Ie. using pure aluminum then adding any alloying components needed. there is no cost effective way to get a precise alloy without pure ingredients. But for timing pulleys, you don't need a precise alloy.

Timing pulleys need a mill and precision indexer to make. Not just a lathe. You are also going to need a good set of reusable molds. As others pointed out, you also need a buyer. Timing pulleys are not something you can just sell 10k of immediately.