Sciencemadness Discussion Board

Disassembling ZN/C battery to obtain zinc dust

maxpayne - 27-5-2012 at 10:48

I need to obtain some zinc metal, so i decided to take it from old heavy duty zinc/carbon battery.

Since battery are more or less tough to disassemble, I thought the hand saw might help to do the job faster. Then I could simply pull out the carbon rod, stress out manganese dioxide to be left with zinc outer shell.

Are there any dangers if I simply hand saw through the battery, and what would be the best way to clean zinc shell and grind it to dust?

[Edited on 27-5-2012 by maxpayne]

hissingnoise - 27-5-2012 at 12:06

Zinc powder isn't expensive; why not just buy it?

maxpayne - 27-5-2012 at 12:15

Not expensive if you need much, but I need about 10-20 grams, no more. So batteries are more economical in my case. I have loads of old batteries in my attic.

So, is it safe to cut through battery with hand saw? What are possibilities for explosion?

Vargouille - 27-5-2012 at 12:37

If you have C batteries, some of them (Duracell I know does) have a bag of zinc in the middle. You just have to wash it and let it dry and you'll be good. There are some strange white balls mixed in with the zinc though, and I was unable to remove those without a lot of work, and I still think there are a bunch left. Hopefully they won't mess with whatever you need the zinc for.

Roger86 - 27-5-2012 at 15:09

I have experience with this specific type of batteries.

I can tell you there is absolutely no need for a saw, as those batteries are the cheapest available and also have tendency for being the easiest to dissassemble.I have extracted more than kilo of manganese dioxide from these by using just ordinary scissors :)

The worst thing about sawing them is you risk damaging the carbon rod, witch is made from graphite and is the best OTC solution for electrodes.Dont waste them.

Also, if you dont know how to tell the type of the battery, make sure you learn it.When i started, i opened an alkaline battery and sprayed ammonia all over my house, the smell :( Also, note that MnO2 is unpleasant to remove if stains should occur, unless of course you are willing to use powerful chemicals...

maxpayne - 28-5-2012 at 06:59

Thank you Roger86.

My main concern was some kind of explosion that could occur while sawing through. I remember as a kid, I was heating with lighter this kind of battery and it exploded, none damage done :) Just to say, I don't like explosions at all.

Nice thing about graphite rod for electrolysis, however, I already have them, need zinc only. So, I'll saw them, maybe upload a pictures, but what about the purification of zinc shell, and gritting it to dust?

99chemicals - 28-5-2012 at 10:24

A pipe cutter used for cutting copper pipes work very well for opening batteries. I have used it many times before to open the 6v lantern battery cells.

If you are opening an alkaline battery that make sure the liquid doesn't splash on you wear eye protection and a face shield if you have one.

I opened up a alkaline battery once with a pipe cutter and got the KOH solution all over myself.:o I didn't get any in my eyes luckily. I only got it on my arms and managed to wash it off.

Roger86 - 29-5-2012 at 18:26

I suggest you take a closer look at this photo i link from wikipedia.

I was unable to direct link it to this, because the forum software detects the :D part of the link as smiley.It should however work now.

As you can see, the amount of zinc in a battery is quite small.Most of that is MnO2 and the graphite rod.Not the way i'd obtain my zinc, but i'm assuming you're just going to dig the batteries from recycle thrash, as would i.So since there is no cost of materials, i wouldn't discourage you.

I'dont know where you are located, but here in Finland, grocery stores have cardboard boxes you can put the batteries in for free and they dispose of them for you.I have asked a few times if i could have some of the batteries for me, and they just let me have as much as i want.

On such scenario, i would pick more than the one type of batteries.This might not intrest everyone, but for some unexplainable reason i would like to have some Cadmium...

Arthur Dent - 30-5-2012 at 05:02

The zinc casing of standard carbon/zinc batteries is my main source for clean, pure zinc. After several experimentations, I can confirm that the washed and cleaned casings gives me very clean zinc salts with no Fe or Mn impurities.

My trick is to use a pair of wire snippers to cut a small dent on top of the battery where the zinc envelope and the steel top button meet, and then grab the edge of the zinc casing and just peel it by holding the base of the battery with a silicon-covered vise grip. The long Zn strip can then be washed with soap and water, and then dipped in hydrochloric for a few seconds. You can then do whatever you want with the resulting zinc. Big "D" batteries are best because the outer shell is quite massive.

If you want Zinc dust, you can grind the cleaned zinc casings with a file (zinc is quite soft and easily ground).

It's just a mess to try to recuperate Zinc or MnO2 from Alkaline batteries, and absolutely not worth the trouble. Tried it once, got the KOH shower, never tried again. Lesson learned.


S.C. Wack - 30-5-2012 at 12:53

Quote: Originally posted by Arthur Dent  
It's just a mess to try to recuperate Zinc or MnO2 from Alkaline batteries, and absolutely not worth the trouble.

IMHO it's no trouble at all, and have probably said so in several identical threads. No law against puncturing under water. It's certainly an easier way to get zinc powder (certain brands at least) than powdering (molten) battery casings.

maxpayne - 3-6-2012 at 11:04

Today, I crushed one of the D battery with sledgehammer. I didn't know if it was an alkaline or not, so I put it under a thin metal sheet and beat it up :D

What I left with was broken carbon rod, manganese dioxide and of course zinc metal. I detached the zinc metal of protective sheet and cleaned it with toothbrush under soapy water and now all I need to do is to grind it. It took me about 5 minutes. This is the fastest and simplest way to get zinc from battery.

Final yield: little more than 10 grams of pure zinc from D type Zn/C battery.

I also found a video where carbon rod can easily be saved by punching the negative pole gently with a hammer. Don't recommend to punch alkaline batteries though.

Pyro - 3-6-2012 at 12:21

you are better off getting your things from the batteries that Nurdrage uses, you can take apart those with a screwdriver.