5 replies to this topic

[GreenGenie]

I bought some charcoal powder a few months ago from http://www.charcoaldust.co.uk/. Some airfloat, some willow and some lumpwood. The airfloat and the willow seemed ok. The lumpwood contained a lot of very coarse material and was slightly damp. The dampness was not apparent to the eye or by touch; but when I put the charcoal in a tupperware box droplets of moisture would form on the underside of the lid overnight.

Having recently bought a ball mill I thought - no problem, the ball mill will turn that to a fine powder. I put the charcoal in and left it turning overnight. When I opened the drum the mill had produced some standing liquid and the charcoal had turned into a stiff cake like consistency. This came as quite a surprise. I had to use a knife to scrape the drum clean.

Water is clearly the problem I thought. Ok no problem. Its a very hot day. So I left the charcoal and the drums exposed to the full glare of a hot sunny day for 6 hours and the material seemed to dry out well. I milled it again. Again overnight. I opened the drum the next day and whilst there was an improvement (No dampness seemed to be present) still the charcoal was very lumpy. The charcoal had clumped together and formed particles varying in size from fine powder up to a large lump about an inch and a half across. Less than 50% of this material could be said to be a powder. The material is in a far worse condition that it was in when I first bought it.

Clearly there is more to milling charcoal than simply putting it in a ball mill and letting nature take its course. What have I done wrong? What is the correct method for doing this?

As I have had unexpected results milling both nitrate and charcoal I am also asking for advice on milling BP as this is what I plan to do next.

Once again I ask for the wise heads in the group to help a green horn newcomer.

[knackers]

Clearly there is more to milling charcoal than simply putting it in a ball mill and letting nature take its course. What have I done wrong? What is the correct method for doing this?

you havn't done anything wrong GG, and it is as simple as you describe, unfortunately you have aquired a little moisture, ( perhaps alot ), that can pose 2 problems, 1 :- you would under weigh the compossition quantities and 2:- it may go mouldy after time,
just dry it out, , put it in a paper bag somewhere in a sunny spot then at night put it in a warm room, then pop it back out in a sunny spot again till dry, pop it in the oven on low temp or make up a drying box, " wooden box with a light bulb in it " and place it in there,
your charcoal is still ok,
if you ever happen upon those little silica gel sachets, grab a few and put then in with you stuff, i do and they work great,

Edit :- as for milling Bp, some prefer to moisten their product in the mill jar and mill slightly damp, However, i don't as i find this is too messy and to much mucking about for me. I bung all my chemicals, " well the neccesary ones" all in together dry, switch it on and leave it for a few hours,
if your Kno3 is hard prill form you may wish to grind that up first, i don't and have no problems

Edited by phill 63, 05 June 2009 - 08:45 AM.

[pyrotrev]

You could probably be even more vicious about your drying and not harm it at all - after all it would have been carbonised at >350C to start with. I dry such stuff (but NEVER compositions obviously ) in the oven set at about 130 - but not when the missus is baking though

[GreenGenie]

Thanks guys

I really appreciate this. Without your advice I would be stuck and not know how to move forward.

Despite my drying out the charcoal in a full hot sun for six hours I can see that you are right. I have seen more evidence of condensation inside the tupperware box that I have it in.

I have an infra red light heat lamp that I bought for drying out some chemicals I am planning on making. It is just what is needed.

Thanks again.

[Arthur Brown]

"Dried to constant weight" is a phrase from my lab days! It means exactly as it says. Dry the product until further heating dries it no more by weight.

Take "Some" charcoal and weigh it, then make gentle attempts to dry it and weigh it again, and again until it loses no more weight. THEN you can weigh from that the amount you need to use.

If you weigh wet you weigh water then the compound you make is inaccurate.

[sir steve]

I bought some charcoal powder a few months ago from http://www.charcoaldust.co.uk/. Some airfloat, some willow and some lumpwood. The airfloat and the willow seemed ok. The lumpwood contained a lot of very coarse material and was slightly damp. The dampness was not apparent to the eye or by touch; but when I put the charcoal in a tupperware box droplets of moisture would form on the underside of the lid overnight.

Having recently bought a ball mill I thought - no problem, the ball mill will turn that to a fine powder. I put the charcoal in and left it turning overnight. When I opened the drum the mill had produced some standing liquid and the charcoal had turned into a stiff cake like consistency. This came as quite a surprise. I had to use a knife to scrape the drum clean.

Water is clearly the problem I thought. Ok no problem. Its a very hot day. So I left the charcoal and the drums exposed to the full glare of a hot sunny day for 6 hours and the material seemed to dry out well. I milled it again. Again overnight. I opened the drum the next day and whilst there was an improvement (No dampness seemed to be present) still the charcoal was very lumpy. The charcoal had clumped together and formed particles varying in size from fine powder up to a large lump about an inch and a half across. Less than 50% of this material could be said to be a powder. The material is in a far worse condition that it was in when I first bought it.

Clearly there is more to milling charcoal than simply putting it in a ball mill and letting nature take its course. What have I done wrong? What is the correct method for doing this?

As I have had unexpected results milling both nitrate and charcoal I am also asking for advice on milling BP as this is what I plan to do next.

Once again I ask for the wise heads in the group to help a green horn newcomer.

rule number 1. never put charcoal in a microwave It can hit 2400 K!

You should be Ok milling BP but make sure you're charcoal has no grit in it, when a ball mill explodes
lead balls are shot in all directions.

Steve



Steve.