nomic
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Dichloromethane (Methylene Chloride) MDC
hi guys looking for some help
i want to create a decontamination bath / alloy wheel stripping bath to remove powder coat etc from alloy wheels.
now i know the most popular solution is Dichloromethane (Methylene Chloride) MDC but it costs £99 per 25 ltrs and i need approx 400 ltrs for an
adequately sized stripping tank.
now i can get methanol for £12.50 per 25ltrs so i am wondering if there is a way to turn methanol into a stripping solution like Dichloromethane
(Methylene Chloride) MDC to keep it more cost effective.
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Oscilllator
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You cannot turn methanol into DCM in an economical manner on the scale you have described. However if you need 400L of DCM You should be able to buy
it cheaper than the $4/L that you pay for 25L.
Nonetheless, $4/L is quite cheap. Where do you buy your dichloromethane from?
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Amos
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Quote: Originally posted by Oscilllator  | You cannot turn methanol into DCM in an economical manner on the scale you have described. However if you need 400L of DCM You should be able to buy
it cheaper than the $4/L that you pay for 25L.
Nonetheless, $4/L is quite cheap. Where do you buy your dichloromethane from? |
He did quote the price in pounds. So it's more like $6.57/L, not sure if that's cheap or not.
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Oscilllator
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Oops, should have picked up on that.
I know that on a large scale most organic solvents are around $1/L or less, but I don't know if this holds true for chlorinated solvents. nomic you
might want to investigate the use of other, cheaper solvents. I can't recommend any because you haven't told us precisely what you are trying to
dissolve, but if you did that then maybe we could help.
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Amos
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Until he responds, here's something to work with:
http://en.wikipedia.org/wiki/Powder_coating
Most likely polyethylene, polyurethane, or some kind of epoxy. Hence why dichloromethane would be a great choice.
You can buy a metric ton (about 750 liters) of CH2Cl2 on alibaba for $550 max, sounds like a good deal to me, though that's minus shipping from China.
[Edited on 9-2-2014 by No Tears Only Dreams Now]
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nomic
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hi guys its for dissolving electrostatic powder coat paint off alloy wheels and yes its £ im in the UK
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nomic
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sorry for the long wair for reply i was in the middle of watching a film and the wiki above is exactly what i am doing
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nomic
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the shipping from china would be around £150 + import tax which would be around £100 + initial cost im looking at £600 total convert that back to $
roughly $1000 total cost
[Edited on 2-9-2014 by nomic]
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Oscilllator
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| Quote: Originally posted by nomic | | hi guys its for dissolving electrostatic powder coat paint off alloy wheels and yes its £ im in the UK |
Yes but what is the paint made of? If it is indeed something like polyester, you *may* be able to use acetone, which should be a fair bit cheaper than
dichloromethane. The wiki page linked supports this view.
A quick look on alibaba reveals a price of ~$2/kg for acetone, so this looks like a very viable alternative.
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nomic
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ill check the specs
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nomic
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cant find the spec on these charts will have to check with the supplier its a new project so still learning
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nomic
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thanks guys ill look at the acetone route
[Edited on 2-9-2014 by nomic]
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Oscilllator
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Ok. In future, please avoid posting several times sequentially. The edit button is there for situations like this.
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IrC
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I would carefully study the hazards using DCM in a large open vat which would be required for putting something as large as rims in and completely
submerging them. DCM evaporates quickly and the volume of vapors would be large and of high concentration. Rapidly converted into CO in the blood
through inhalation or skin contact. Very often with fatal consequences. From: http://en.wikipedia.org/wiki/Dichloromethane "In February 2013, the U.S. Occupational Safety and Health Administration (OSHA) and the National
Institute for Occupational Safety and Health warned that at least 14 bathtub refinishers have died since 2000 from DCM exposure.".
I mention this because in 1981 I was using large amounts in open containers to de-pot circuit boards and nearly became one of the statistics. There
was no internet to find such information easily and quickly. In fact in 81 it was difficult to obtain any information on the dangers of nearly
everything we use. MSDS's are general and vague, so much so they are useless even in this day and age. Be very careful with the dangers of inhalation
and skin absorption when you set up your operation.
"Science is the belief in the ignorance of the experts" Richard Feynman
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Dr.Bob
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One place I worked used to make paint stripper from recovered solvents. Most were based on DCM with about 70-90 % DCM, and then 5-10% of methanol,
toluene, and traces of others like acetone, hydrocarbons (hexane, kerosene, paint thinner, etc). I have found that in some cases, a smaller amount
of DCM in other hydrocarbon solvents will work OK and be less volatile, such as DCM and paint thinner (mostly hydrocarbon based, like kerosene or
Skelly-solve type hydrocarbon mix). But more polar solvents like methanol and acetone cannot be too much of the mix, for most paints, or they slow
done the paint removal.
But you will need a reasonable amount of DCM to remove baked on paints/powder coats. In some cases paraffin is added to help reduce the evaporation
of the solvents, but then you MUST rinse the parts in clean DCM or hydrocarbons to remove the paraffin. For latex type paints, there are other
solvents like non-polar ester and ethers. As well, some tasks you can use aqueous hydroxide caustic mixtures, but that would corrode your aluminum.
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unionised
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Just a quick heads up.
"Dichloromethane is incompatible with ... alloys of aluminum, magnesium and zinc. "
from
http://www.chemicalbook.com/ChemicalProductProperty_EN_CB774...
And
"Pure anhydrous methanol is mildly corrosive to lead and aluminum alloys"
from
http://www.methanol.org/health-and-safety/frequently-asked-q...
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