isopropyl alcohol filter

[sphelps]

Originally Posted by superduperwesman

Build a separator. As long as the particles are heavier then the alcohol they should drop out given the right conditions to do so. No mechanical filtration needed. Just let gravity do it's job and all you need is 2 baffles. Just have to size in correctly?

Will that work if the oil is dissolved? Doesn't this only work for sediment?

[superduperwesman]

I never saw the oil part just the small particle part. So the oil will actually dissolve into the alcohol?

[vic622]

Originally Posted by sphelps

Will that work if the oil is dissolved? Doesn't this only work for sediment?

I'd have to ask my mgr, who's a solvent extraction specialist, but I suspect you're going to need to do some sort of solvent extraction or use a special media bed (same principle as in DI media).

I don't think you'll be able to just do a mass separation as you're having an attraction between the functional groups in the oil & alcohol.

You might contact Dow, Fisher or Anachemia to see what media they have that might be appropriate for your application.

[Kryptic4L]

you could always set up the filtration for after the wash, chemical r/o back into the tank and reuse. I would also think that sediment may also be your friend in this type of system, as it would offer some abrasiveness for scrubby bubbles

[sphelps]

Originally Posted by superduperwesman

I never saw the oil part just the small particle part. So the oil will actually dissolve into the alcohol?

Yeap which is why it's used as a solvent.

Originally Posted by vic622

I'd have to ask my mgr, who's a solvent extraction specialist, but I suspect you're going to need to do some sort of solvent extraction or use a special media bed (same principle as in DI media).

I don't think you'll be able to just do a mass separation as you're having an attraction between the functional groups in the oil & alcohol.

You might contact Dow, Fisher or Anachemia to see what media they have that might be appropriate for your application.

Good info, thanks

[sphelps]

Originally Posted by Kryptic4L

you could always set up the filtration for after the wash, chemical r/o back into the tank and reuse. I would also think that sediment may also be your friend in this type of system, as it would offer some abrasiveness for scrubby bubbles

That's kind of what I was thinking, a separate unit to filter the alcohol between washes as required. I've never heard of a chemical R/O before, could you elaborate? If it's anything like the water ro with a 4 to 1 waste ratio it would be much good. I can't invest in something that will only recover a small portion of the alcohol, it has to be the majority if not all.
Also the sediment won't be beneficial, the parts are actually pretty clean when they go in but there will be traces of grit from the sandblaster and oil from heat treating as well as whatever chemicals are used in the powder coating or plating processes. If any particles remain on the surface the gauging process could fail which is not good.

[sphelps]

I ordered some oil absorbing mat which can be used to filter oil from water however I'm pretty sure it's not going to work. A little research shows the mat absorbs all hydrocarbons so water can obviously pass through because it's not a hydrocarbon but alcohol is a hydrocarbon so I think this experiment is already flawed.

[sphelps]

OK so the mat is out, it absorbed the alcohol as well and the solution that did make it through contained the same amount of oil. Basically in this application it's just expensive cloth.

[superduperwesman]

Prob have to use some solvent as mentioned, or some kinda flash tank. The alcohol should boil around 84 C but the oil would be much higher so you could prob separate them this way? Any reason why the parts washer can't run with warm-> hot alcohol?

[sphelps]

Originally Posted by superduperwesman

Prob have to use some solvent as mentioned, or some kinda flash tank. The alcohol should boil around 84 C but the oil would be much higher so you could prob separate them this way? Any reason why the parts washer can't run with warm-> hot alcohol?

Yeah fractional distillation would be the best way to reuse the alcohol but this is something I'd rather avoid. Our production staff are not the most careful people around and I don't mean to say they aren't smart but they have managed to do some pretty stupid things. The last thing I want is to add is highly flammable vapor into their routine, I'd much rather keep things simple and safe if possible. Also have to consider the cost of distilling, the energy required for the process is significant in comparison to the cost of the alcohol.

I don't want to heat up the alcohol in the washer either, this would not exactly be safe. I actually have a thermo switch installed which shuts the system down if the fluid gets too warm.