RogueRose
International Hazard
Posts: 1593
Registered: 16-6-2014
Member Is Offline
|
|
Phosphors from CRT's - large amount recovered - What can be done?
So let's say someone has about 30lbs of phosphor from the inside of CRT's, both TV's and monitors and maybe 3-4lbs of phosphor from HPS/MH bulbs. It
seems there is a wide variation of composition between what makes up these phosphors from some rare earth minerals, to silver to many common elements.
the funny thing is that after looking a a VERY long list of about 400+ types of phosphor, I don't think I ever saw the big "P" on the list anywhere
(bummer). I was thinking that phosphorus could be made from this stuff.
I'm wondering if during a recycling process, is it OK to collect it all from all sources into one location and then send the collected powered out for
processing? Seeing that it is near impossible to tell the composition by looking at it (and models change the type used between runs sometimes),
there aren't many options when dealing with this.
Does anyone have any interesting facts, thoughts or ideas on CRT/light bulb phosphors?
|
|
Radium212
Hazard to Self
Posts: 85
Registered: 26-6-2017
Member Is Offline
Mood: Pyrophoric.
|
|
Well if you've mixed them together that's buggered any chances of selecting certain phosphors. But if you have just the CRT phosphors you could use
them in homemade CRTs, or maybe spinthariscopes. Yeah, build a little spinthariscope. How much would you charge for say 5g of a zinc sulphide
phosphor, just out of curiosity.
|
|
Radium212
Hazard to Self
Posts: 85
Registered: 26-6-2017
Member Is Offline
Mood: Pyrophoric.
|
|
Oh and be careful about the light bulb phosphor. It may be contaminated with mercury.
|
|
unionised
International Hazard
Posts: 5126
Registered: 1-11-2003
Location: UK
Member Is Offline
Mood: No Mood
|
|
I doubt there's much market for 2nd hand phosphors, especially wen they are mixed up.
Most phosphors don't contain phosphorus and, if even they did, it would be easier and cheaper to get phosphorus from bone ash.
|
|
RogueRose
International Hazard
Posts: 1593
Registered: 16-6-2014
Member Is Offline
|
|
Is all the phosphor in CRT's (TV's and Monitors) the same? I looked on Wiki and they listed A LOT of phosphors and there were maybe 4-6 for CRT's if
I remember correctly. Also the HPS/MH had almost the same number of types as well and it depended upon the color that was wanted from the light.
I don't have the phosphor but the person processing them does. I can contact them and see what they have and if they are seperating CRT and bulb
phosphor.
|
|
unionised
International Hazard
Posts: 5126
Registered: 1-11-2003
Location: UK
Member Is Offline
Mood: No Mood
|
|
No.
|
|
Radium212
Hazard to Self
Posts: 85
Registered: 26-6-2017
Member Is Offline
Mood: Pyrophoric.
|
|
I suppose you might be able to flog them on eBay or something. Mixing them together was a bad move though. And where the hell did you get all this?
|
|
RogueRose
International Hazard
Posts: 1593
Registered: 16-6-2014
Member Is Offline
|
|
A guy who does recycling has been collecting it from CRT's for about 3 years.
AS far as making phosphorus, I know of two sources of P in my area. Bone ash and Triple Super Phosphate (0-45-0) which is a calcium based fertilizer.
Actually there is also something called soft rock phosphate which is about 0-13-0 to 0-20-0 and is calcium based as well. It's almost the same price
as the triple so it seems a no brainer.
IDK how phosphorus is extracted in any way, but I know that the bone ash has MUCH less P than the triple super phosphate.
Can the triple phosphate be used to make P? I'm guessing it can be used to make H3PO4 and I'm guessing P can be made from that. P is one compound
i've never really read up on.
|
|
PirateDocBrown
National Hazard
Posts: 570
Registered: 27-11-2016
Location: Minnesota
Member Is Offline
Mood: No Mood
|
|
You can use CaH2PO4.H2O (triple "super" phosphate) to make P. But there are several caveats:
1)You need high temps. Carbothermal reactions can work, or thermite types, done in an air-excluded environment. Since glass will melt at these temps,
you need a metal retort.
2) You need a means of capturing the P underwater. It will be white P, formed at these temperatures. Otherwise, it will burn immediately. Take all
other precautions for white P, as well.
3) Presence of hydrogen in your reactants will cause the formation of pyrophoric phosphene gas, PH3. This stuff robs you of your product, is toxic as
hell, and stinks, to boot. To avoid its formation, make your reactants anhydrous, and choose ones that have no hydrogens. So you will need to convert
your CaH2PO4 to something else. Many have used Na3PO4, anhydrous.
4) What you get will likely be rather dirty. You should have in mind uses for the product that are tolerant of such contamination, or have planned
some means of purifiying your product.
|
|
Radium212
Hazard to Self
Posts: 85
Registered: 26-6-2017
Member Is Offline
Mood: Pyrophoric.
|
|
Maybe you could purify your dirty product through dissolution in carbon disulfide?
|
|
Sulaiman
International Hazard
Posts: 3696
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
Does anyone have any interesting facts, thoughts or ideas on CRT/light bulb phosphors?
Just to repeat Radium212's comment about Spinthariscopes;
https://en.wikipedia.org/wiki/Spinthariscope
IF you have access to a radioactive source such as Am
AND a x10 or more eyepiece or magnifying glass, even better a microscope etc.
then I really recommend making a Spinthariscope
quick, easy, pretty.
By varying the distance between source and screen the image changes from a few random stars (tiny bursts of light) to a boiling cloud (in 2D only) ...
I think worth seeing.
I imagine the effect with mixed phosphours could be quite psychedelic ... sellable
(I've never heard of a Color Spinthariscope)
EDIT: removed 'usb' from 'usb microscope' as I have not actually tried with a usb microscope, and the lightb levels are probably too low.
Also, I forgot to mention;
if you do make a spinthariscope you need to use it in a really dark room after many minutes of dark-adaptation ... up to 30 minutes.
[Edited on 2-1-2018 by Sulaiman]
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|