aluminium potassium sulphate and copper sulphate crystals

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mtg
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aluminium potassium sulphate and copper sulphate crystals

Post by mtg »

I have heaps on CuSO4 and AlKSO4 waste crystals and I was wondering if anyone has a prac or activity that would use it all. I wonder if we could make a big crystal with it all, as I've seen huge CuSO4 crystals. if I dissolve it all and evaporate some of the liquid to concentrate it a bit would the seed crystal theory work? Otherwise where do you get rid of it, seems overkill to send it off for chemical collection.
Merilyn1
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by Merilyn1 »

I'm stuck with heaps of copper sulfate waste, too. I've evaporated it down and could use it to make a saturated solution, but we never seem to need it here. I also have a couple of winchesters of mixed copper waste, but I know it is mostly c/sulfate. I have left it in a beaker to evaporate, to reduce the volume, which helps. I can't put any down the sink because of the septic system - so the usual methods are no good as there is still a chance of residual copper going down the sink.
At this stage, I am just sending it off for disposal.
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Milo
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by Milo »

There are ways to treat copper sulfate to make it safe for disposal. One I've heard mentioned is putting steel wool in it, although I haven't yet tried it myself. There's a recommendation for this on Science Assist:
https://assist.asta.edu.au/question/431 ... id=3be8dee
Smithy73
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by Smithy73 »

Once you have grown your copper sulphate crystals and finished looking at them you can grind them back to a powder and store them away for next time. Saves on a lot of waste. We have done this for a couple of years and haven't had any issues with them reforming, I also keep some whole as seeds if needed.
J.Speaks
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by J.Speaks »

mtg wrote: 23 Oct 2019, 11:37 I wonder if we could make a big crystal with it all, as I've seen huge CuSO4 crystals.
I'm actually taking any CuSO4 and Alum crystals from the pracs and resaturating solutions to grow a set of crystals in the prep room. In just a few weeks I've grown a nice looking octahedral Alum crystal that's about 4cm from tip to tip. The CuSO4 didn't come out quite as good (looks like rock candy) but I didn't use the best seed crystal for it. It grows quite quickly tho, so I could probably try to make a better seed crystal from the prac leftovers.
CuSO4 Crystal.jpg
Alum Crystal.jpg
I've given them to the teachers to show the students since it has been a couple of weeks since that prac and they really enjoy seeing the big crystals! I intend to keep growing them all year just to see how big I can get them. Then I'll start over next school year with a new seed :D

No reason we can't have a little fun ourselves, right? \:D/
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semper ubi sub ubi :thumbup:
RosalieL
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by RosalieL »

J.Speaks wrote: 05 Mar 2021, 14:48 No reason we can't have a little fun ourselves, right? \:D/
Absolutely!
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Anna Z
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by Anna Z »

We evaporate off us much as we can then out for DG waste... it's a pain and costs but we are short on space so need to keep our DG store clear. Rather pay a few dollars and have our Chem store safe and clutter free.
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Wayne
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Re: aluminium potassium sulphate and copper sulphate crystals

Post by Wayne »

Anna Z wrote: 07 Mar 2021, 09:44 We evaporate off us much as we can then out for DG waste... it's a pain and costs but we are short on space so need to keep our DG store clear. Rather pay a few dollars and have our Chem store safe and clutter free.
I evaporate it all off and reuse again next year for the same crystallisation prac.
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