Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Stains on hotplate
mr.crow
National Hazard
****




Posts: 884
Registered: 9-9-2009
Location: Canada
Member Is Offline

Mood: 0xFF

[*] posted on 19-10-2010 at 18:05
Stains on hotplate


So my palladium solution splattered all over my hotplate and now it has brown stains that are impossible to get rid of.

Its a Corning PC420 with a ceramic top. Does anyone know how to clean these up?

I assume they are made to be indestructible, even at the hands of undergrads.




Double, double toil and trouble; Fire burn, and caldron bubble
View user's profile View All Posts By User
spirocycle
Hazard to Others
***




Posts: 197
Registered: 29-9-2010
Member Is Offline

Mood: No Mood

[*] posted on 19-10-2010 at 18:28


thats the fanciest stain I've heard of in a while.

"Oh no! my palladium splattered EVERYWHERE!"

but seriously, wouldn't more aqua regia take the stains out?

[Edited on 20-10-2010 by spirocycle]
View user's profile View All Posts By User
Magic Muzzlet
Hazard to Others
***




Posts: 146
Registered: 22-7-2010
Member Is Offline

Mood: No Mood

[*] posted on 19-10-2010 at 18:36


I guarantee you will stain the hell out of your hotplate anyway, why does it matter if it is stained?
I have no idea how to remove them, by the way.
:cool:
View user's profile View All Posts By User
Justin
Hazard to Self
**




Posts: 84
Registered: 6-5-2010
Member Is Offline

Mood: No Mood

[*] posted on 19-10-2010 at 19:20


I have a corning PC220 with ceramic top and its stained also, your probably not gonna get the stains off because the ceramic is porous. But hey atleast your hotplate got "sum bling bling"
View user's profile View All Posts By User
mr.crow
National Hazard
****




Posts: 884
Registered: 9-9-2009
Location: Canada
Member Is Offline

Mood: 0xFF

[*] posted on 20-10-2010 at 06:43


I guess it has some character now!

All the other stains burnt off by themselves




Double, double toil and trouble; Fire burn, and caldron bubble
View user's profile View All Posts By User
Magpie
lab constructor
*****




Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline

Mood: Chemistry: the subtle science.

[*] posted on 20-10-2010 at 12:56


The kitchen is your friend:

Kitchen Friends.JPG - 42kB




The single most important condition for a successful synthesis is good mixing - Nicodem
View user's profile View All Posts By User
harderm
Harmless
*




Posts: 9
Registered: 22-10-2010
Member Is Offline

Mood: pistoff

[*] posted on 22-10-2010 at 22:54


How much Pd are you missing? If this is insignificant, I say fuggedaboutit.:cool:
View user's profile View All Posts By User
mr.crow
National Hazard
****




Posts: 884
Registered: 9-9-2009
Location: Canada
Member Is Offline

Mood: 0xFF

[*] posted on 24-10-2010 at 10:48


Thanks, now its nice and clean and smells like lemons

Yeah not enough went missing to bother with




Double, double toil and trouble; Fire burn, and caldron bubble
View user's profile View All Posts By User
The WiZard is In
International Hazard
*****




Posts: 1617
Registered: 3-4-2010
Member Is Offline

Mood: No Mood

[*] posted on 25-10-2010 at 06:54


Quote: Originally posted by mr.crow  
So my palladium solution splattered all over my hotplate and now it has brown stains
that are impossible to get rid of.


An oxalic acid sol. will chelate most metals. A traditional use
was removal of blue/green copper stains in the home bathtubs and
such. People would boil o acid containing rhubarb leaves to clean
their steel pots.


djh
----
Hilarius (Hillary) ST. —

In 259 Hilary attended the convocation of bishops at Seleucia in Isauria, where,
with the Egyptian Athanasians, he joined the Homoiousian majority against the
Arainizing party headed by Acacius of Caesarea; thence he went to
Constantinople , and, in a petition (Ad Constantium Augustum liber secundus)
personally presented to the emperor in 360, repudiated in the calumnies of his
enemies and sought to vindicate his Trinitarian principles.
View user's profile View All Posts By User
peach
Bon Vivant
*****




Posts: 1428
Registered: 14-11-2008
Member Is Offline

Mood: No Mood

[*] posted on 28-10-2010 at 07:20


Quote: Originally posted by spirocycle  
thats the fanciest stain I've heard of in a while.

"Oh no! my palladium splattered EVERYWHERE!"
[Edited on 20-10-2010 by spirocycle]


:D

And NOW all my diamond grit is in the grout lines on the floor!

Nah, but I agree with the others, it's GOING to get stained if you're using it.

Mine has reached points where the entire ceramic top was virtually black with gunk. By simply turning it up all the way to full and leaving it running for a few hours, I've come back and found it virtually spotless, as the heat has burnt the organic muck off.

They'll do that with glassware in some organic labs. When washing doesn't work, stick it in the furnace, turn it up and go home. The heat burns anything organic off and it comes out nice and clean.

[Edited on 28-10-2010 by peach]




View user's profile View All Posts By User
digitalemu
Harmless
*




Posts: 38
Registered: 21-10-2010
Member Is Offline

Mood: No Mood

wink.gif posted on 29-10-2010 at 11:29


Worrying about stains on a hotplate is about the same as worrying about acid holes in your lab coat. If there are no holes and stains your not a chemist. :)
View user's profile View All Posts By User
peach
Bon Vivant
*****




Posts: 1428
Registered: 14-11-2008
Member Is Offline

Mood: No Mood

[*] posted on 29-10-2010 at 14:18


You should see my underpants.

As soon as I find the camera, I'll get you a picture.

There are more holes in them than a piece of swiss cheese. I always wear the same pair when doing chemistry for the acid reason.

I'm actually having a bit of a competition to see if I can genuinely wear out a pair of underpants. When they become illegal or fall apart, I'll feel all sad inside. They've been good friends, and I feel their time is nearing.

Underpants and legality are a major concern for me, as I often don't wear any and have been around very large groups of school kids on a frequent basis. As such, forgetting to do my zipper up could result in a serious criminal charge that wasn't even intentional.

If you're worried about mess on the hotplate, you can always cover the top with foil. If you cover the hole thing, you'll melt the casing or overheat it. And if it's permanently covered with wrinkled, mucky foil, where's the gain there?

I bet loads of the guys who buy IKA plates new never use the things in case they get a bit of muck of them. :P

So many chemicals will massively stain things on a drop or two of them making contact, it's basically going to happen. I've managed to stain PTFE stir bars pitch black without too much trouble.

Our chemistry labs at school paid hundreds and hundreds of pounds each for chemically resistant bench tops that were theoretically unstainable. Sure enough, they eventually went down, after one of the staff members spilled some form of concentrated iodine solution on it and it wouldn't come back out.

It was funny watching the pedantic inogranics teacher scrubbing at it every now and again, hoping it'd go away again. It didn't.

[Edited on 29-10-2010 by peach]




View user's profile View All Posts By User
mr.crow
National Hazard
****




Posts: 884
Registered: 9-9-2009
Location: Canada
Member Is Offline

Mood: 0xFF

[*] posted on 30-10-2010 at 08:58


Quote: Originally posted by peach  
You should see my underpants.


Oh Peach, quite the charmer.

I got the hotplate used too, so I am surprised it wasn't already messed up. There was a bunch of unknown crap inside it that someone spilled. Its designed to have stuff spill on it.

It came from the States, so I got a very unwanted $90 charge from UPS. Never use UPS, they suck monkey fuck.

I find most of the stains burn off too. I tired Al foil but the boiling acid burned little holes through it.




Double, double toil and trouble; Fire burn, and caldron bubble
View user's profile View All Posts By User
peach
Bon Vivant
*****




Posts: 1428
Registered: 14-11-2008
Member Is Offline

Mood: No Mood

[*] posted on 31-10-2010 at 04:20


The United State Postal Service, the US version of the Royal Mail, usually has the lowest prices. Far lower than UPS. It's easy to use as well because they do the standard box sizes now. "Will it fit in this box? Does it weigh less than 2kg? Which country is it going to? It's this much." Far less messing around.

I've had quite a bit shipped transatlantic with them and it's been great. They used to offer the 6 week ground service for really cheap postage, but that's been stopped now I think and the cheapest is 2 weeks (I think...).

Charges, you don't want to live in the UK then! When a box full of hundreds of pounds worth of things turns up from the US, the VAT and Duty on it can be eye watering. It used to be worse because the Royal Mail would turn up at 7.33am and immediately want £94.72 in cash. "Yeah... let me just check my pocket... nah, haven't got that to hand" as I rub the sleep out of my eyes.

The biggest problem for my hotplate has been the pots (the variable resistors on behind the dials). Reactive gases have gotten into the casing and seem to have ruined the tracks. I suspected something fishy as afoot with it months ago. Then I finally bothered to try using the software that came with my datalogging pH / temperature meter and drew a graph for a flask of water I had on the plate.

I tried turning the heating up one increment at a time and noticed that not only was it not anywhere close to a straight / smooth line, it was changing fk'ing sign! Going from hotter to colder as I raised the number on the dial.

Anyway, fixing that will be as expensive as soldering some new pots on. But it wouldn't have been a problem if they'd stuck some little 1p o-rings over the shafts as they put it together, which I will do in part 2, the long needed clean up and fix up it's been deserving.

IKA plates will be even worse for that, as I think those use rotary encoders for the dials, which are quite a bit more expensive than pots. Hopefully, they've actually sealed the shafts to the casing. If not, that's a joke considering the price tag.

{edit - the Royal Mail}
I love the RM, but their parcel section, Parcel Force, is odd. The RM was privatized and then locked into providing standard RM services / charges, I believe they're being freed of this, this year. The idea was to drive the costs down. But, ironically, Parcel Force has continued charging £15 as a flat starting rate on all parcels, whereas I can get the same thing shipped for £7 by many, many other couriers. So.... ruin the RM, retain prices that are double everyone else's? If they don't drop, in half, this year or the next, it's going to die. There is also some odd things going on with regards to what you call the shipment. I quoted one guy £75 to ship some guitar pickups to him as a parcel through parcel force. When I went to post them, she said "Send it as a packet, it'll be £1.70". :o That's getting on for two orders of magnitude difference in price, make your mind up!

[Edited on 31-10-2010 by peach]




View user's profile View All Posts By User
food
Hazard to Self
**




Posts: 86
Registered: 4-9-2010
Location: the West
Member Is Offline

Mood: mithering

[*] posted on 31-10-2010 at 08:03


Quote: Originally posted by peach  
You should see my underpants.


.. er ?

we have, old boy

the brief, and tastefully lit, glimpse provided by your youtube lithium spectra production :)
View user's profile View All Posts By User
peach
Bon Vivant
*****




Posts: 1428
Registered: 14-11-2008
Member Is Offline

Mood: No Mood

[*] posted on 1-11-2010 at 09:58


Those are only the beginning.



View user's profile View All Posts By User
DougTheMapper
Hazard to Others
***




Posts: 145
Registered: 20-7-2008
Location: Michigan, USA
Member Is Offline

Mood: Energetic

[*] posted on 4-11-2010 at 12:36


I have a Scholar 170 with a ceramic top that has been severely pitted by molten NaOH. I paid way too much for it... the heat control is just this adjustable bimetallic strip affair; it's reasonably temperature-accurate but annoying as it clicks on and off every few seconds. I can imagine the contact points eventually giving up or welding themselves together at the most inopportune time...
View user's profile View All Posts By User

  Go To Top