Fantasma4500
International Hazard
Posts: 1681
Registered: 12-12-2012
Location: Dysrope (aka europe)
Member Is Offline
Mood: dangerously practical
|
|
Graphite electrodes from car brakes?
so, my job got about 20 tonnes of car / truck / machine brakes hauled in packed in cardboard boxes, and no one seemed to know what the hell these
brakes are really made of except for the steel part, theres a blackish side that takes all the grinding force on it that seems to have some metallic
particles inside of it
it seems to be mounted on the steel with some kind of epoxy- so, torched it for a bit to ruin the epoxy (it gets brittle once it has been heated a
bit)
the thing came off along with some very unhealthy smoke, and as i was torching it, it sure glowed like graphite, the thing doesnt seem to be any more
fragile than it was before, and after some reading im finding online that its made of a mix of metals, some epoxy and graphite
now, i get a 10 year old flashback to one guy talking about rolling graphite dust into epoxy and letting that harden to use as chlorate cell
electrodes- and it worked, but these things have been used for cars since forever? i bet mechanics have these things laying around all the time with
half of it grinded down or whatever, and these factories sometimes gets a small error in their product and decide to throw out tonnes of these things
now. sure, i have not yet tested it, but if this epoxy stuff can hold up to being heated red hot, then im feeling quite confident that it would hold
up for at least 24 hours of chlorine, some of these things are as long as 300mm and 50mm wide, seems about 5mm thick
my only worries in this isnt the epoxy, but the metal dust inside of the whole device, it could cause the thing to crumble apart, but this might be a
splendid source of graphite for electrolysis cells, or, at the very least graphite
i picked off 4 large ones that ill be pulling the graphite off and if it works i wouldnt mind selling it all as i have better electrodes and even some
graphite gouging rods
|
|
|
paulll
Hazard to Others
Posts: 112
Registered: 1-5-2018
Member Is Offline
Mood: It's fine. Really.
|
|
I'd be concerned about what kind of crud the metal in there would generate. You'll soon have lots of Copper ions floating around in your electrolyte,
I'd assume.
|
|
|
Syn the Sizer
National Hazard
Posts: 600
Registered: 12-11-2019
Location: Canada
Member Is Offline
|
|
Ensure you are using newer breaks, they used to use asbestos in some break pads. I used to do core returns at shop and all of our boxes of break pads
had to be labelled with "may contain asbestos".
I do assume most breaks you would get your hands on these days are asbestos free, I don't know when they stopped using it in breaks, but it is still
something to consider.
|
|
|
symboom
International Hazard
Posts: 1143
Registered: 11-11-2010
Location: Wrongplanet
Member Is Offline
Mood: Doing science while it is still legal since 2010
|
|
Phenol formaldehyde resin is frequently used as a binding agent. Graphite can serve as a friction material as well as binding agent. Another friction
material commonly used is zirconium silicate
[Edited on 29-10-2020 by symboom]
|
|
|
Fantasma4500
International Hazard
Posts: 1681
Registered: 12-12-2012
Location: Dysrope (aka europe)
Member Is Offline
Mood: dangerously practical
|
|
im not too concerned about asbestos, its some type of rock like mineral yea? of what i understand the danger with asbestos is that its glass like
shards when its in insulation form which can penetrate your body and remain stuck
it must be some pretty impressive stuff in those brakes, when they drive rally those things can easily get red hot and just cool down a bit and keep
on going, the stuff must be sintered, as for metal contamination that wouldnt be big issue unless youre trying to thermally decompose chlorate into
perchlorate
|
|
|
macckone
Dispenser of practical lab wisdom
Posts: 2168
Registered: 1-3-2013
Location: Over a mile high
Member Is Offline
Mood: Electrical
|
|
Most of the modern brake pads are ceramic not graphite.
The semi-metallic pads do contain metal mixed with ceramic and phenolic resin which turns to graphite and glassy carbon starting at 500C.
Hopefully your brakes aren't getting that hot in operation.
The older semi-metallic pads did contain graphite but I haven't seen these in ages.
There are also organic pads, these probably contain a ton of graphite and phenolic resin.
|
|
|
Fantasma4500
International Hazard
Posts: 1681
Registered: 12-12-2012
Location: Dysrope (aka europe)
Member Is Offline
Mood: dangerously practical
|
|
the vehicles picture on the boxes were hilariously pixelated, could be late 80's or early 90's- i might be sitting on quite the goldmine- alright
thanks for the input, im gonna try to play around with it in the coming week to see if it actually works, if i dont post about it either didnt work or
i died, or both.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
