Disposing of lead and manganese oxides

Discussion in 'Supporting Chemistry' started by Ophelia, Feb 13, 2019.

  1. A teacher recently used these as catalysts for the elephant’s toothpaste reaction. Can anyone advise how to dispose of them that doesn’t involve paying a waste contractor to collect them? I was wondering if I can recycle them by filtering, rinsing and allowing them to dry.
  2. here we use potassium iodide and hydrogen peroxide for elephants toothpaste with a bit of washing up liquid and various food dyes LEAD ?
    manganese oxide ( dioxide) and hydrogen peroxide for collecting oxygen
    the reaction depends on the concentration of the hydrogen peroxide for elephants toothpaste
    Last edited: Feb 13, 2019
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  3. Sorry, I’m not sure what you mean by ‘LEAD’? They used lead oxide.
  4. I think manganese oxide should be fine for recycling as long as you can wash it thoroughly and filter to make sure all the peroxide/washing liquid etc is out of it

    Lead oxide I'm pretty sure you're gonna have to store for waste collection

    However I would be worried about using either as a catalyst for this as both Hazcards mentions to avoid raising dust and this would puff it up fairly spectacularly I'd think....
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  5. I hope someone contacted CLEAPSS for a special risk assessment if using anything other than KI as the catalyst :eek: - this document: http://science.cleapss.org.uk/Resou...y-potassium-iodide-elephant-s-toothpaste.aspx mentions that schools are advised that they should NOT (their emphasis, not mine) deviate from the methods given (using KI) without one - and that this Supplementary RA does NOT (again, their emphasis) cover using manganese dioxide as a catalyst....... :confused:
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  6. I didn’t know they were doing elephant’s toothpaste until afterwards, most of the teachers just provide a list of chemicals and equipment. I often spend some time trying to work out what they plan to do with it! The senior technician has told me to just give them what they ask for.

    Even so, I didn’t know about the CLEAPSS guidance for this reaction. I was a teacher beforehand and have done it using KI, but I’ve only been a technician a few weeks and there’s a lot I don’t know. If I see something obviously dangerous (like the teacher who wanted to do a class practical extracting lead from lead oxide!) I question it, but in this case I didn’t realise. The senior technician knew they were using lead oxide for the reaction, so I guess they didn’t either. The teacher also used iron oxide and (I think) copper sulfate.
  7. I don’t even know if risk assessments are being done :(
  8. Never give out chemicals without knowing what they are doing, find out before because often you can suggest a safer alternative. I would raise this in your curriculum meeting you need to know what practicals they are doing not only for H&S but also to improve your catalog of known experiments. How is your communication with teachers? We are always talking through reqs on a daily basis with teachers.
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  9. I wonder if HSE monitors this site?
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  10. if someone just requests X chemical, do they ask for a certain amount or are you giving out the entire bottle of it?
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  11. I’ve only been here a few weeks, it’s my first technician job (I was a teacher before that). I did ask a lot of questions in my first week but managed to upset a load of people so now I’m just doing what I’m told :(

    One of our prep rooms (the massive one) is also the science staff room so we do have a lot of contact with teachers. So far I’ve found them to be a decent bunch, I’ve spoken to some of them about their reqs if I need clarity on anything.

    We don’t appear to have any technician meetings.
  12. It depends, some ask for a certain amount, some don’t. I’ve been told to put out 4 or 5 bottles of each chemical for a class of 30.
  13. I've been doing this job for over 10 years and I still ask lots of questions, unfortunately I haven't perfected my foresight yet! I would rather my colleague ask questions than potentially send out something hazardous.
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  14. Hi Ophelia

    There are lots of supplementary RA's on the Cleapss website (elephants toothpaste is SRA011) - if you have access :)
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  15. Julie Delaney

    Julie Delaney COMMITTEE

    Lead oxide!!!:eek::eek::eek: why on earth would they use that? That's mad.:eek::eek::eek:
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  16. Yes Lead Oxide is an alternative catalyst for the Elaphant's Toothpaste and is sometimes used to compare catalytic activity.:)
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  17. We use the below experiment as a demo to compare catalysts only we substitute the liver for apple or celery because liver is disgusting. It is on a small scale but they are all set off at the same time so it is still quite visual for the students. The lead one is the fastest and always gets an oooh.

    to dispose I add lots of water, leave solid to settle, pour off excess water wipe up the solid residue using blue roll and put it in my lead solids waste ready for next collection. You can filter if the solid does not sink.

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