freezing crude oil?

[The Omen]

Hi all,

 

Basic question.

 

Is it possible to freeze crude oil or engine oil? If so, how? If not, why?

 

Have had some engine oil in my domestic freezer for roughly 24 hours in a small container. Seems to be getting thicker, doesn't look like it will ever freeze though.

 

Just an experiment for arts sake.

 

Thanks,

[CaptainPanic]

You can freeze it by making it cold... but the freezer that you have might not be enough for engine oil... in fact, if your engine oil could become a solid at the -18 deg C that your freezer can reach, it could mean that your car cannot work at such low temperatures... and cars do work in Canada, North Europe and other cold places. Therefore I dare say that engine oil might be viscous, but still liquid at temperatures well below -18 deg C.

 

Engine oils and crude oil too are mixes of many components. They become more and more viscous, but there will be a point when the first parts start to solidify. I would think that certain components in the oil will first solidify (I am not sure if they will crystallize). Then when you make it even colder, other components will solidify, until finally it is one solid block of oil. Then again, perhaps the really high viscosity can prevent partial solidification, and the whole thing just become more and more viscous until it is hard as a rock.

 

You might have to go to really low temperatures though. I gave it a very quick look on Google, but I couldn't find a melting point of lubricants or crude oil... (which is not weird: they are both whole categories of mixtures... and there's not 1 point at which they melt).

[iNow]

Is it possible to freeze crude oil or engine oil? If so, how?

Yes, as CaptainPanic mentioned... Just make it colder than your freezer is able to.

 

 

 

http://findarticles.com/p/articles/mi_m1511/is_7_21/ai_63035783

A typical bottle of motor oil contains millions of different molecular structures, each of which solidifies at a different temperature, so the oil would not freeze all at once. Natural motor oils become cloudy if cooled below 15 degrees Fahrenheit, as waxy molecules in the oil begin to condense into small crystals. Manufacturers add organic molecules to control the size and growth of these wax crystals, lowering the solidification point to -30 or -35 [degrees] F. Synthetic motor oils, which have more tightly controlled molecular structures, are used in colder climates because they freeze at lower temperatures, but even synthetic oils will solidify at temperatures below -40 [degrees] F. That's why people in Alaska often leave their vehicles running in winter.

[The Omen]

that's great Cap.

 

Would crude oil therefore be easier than engine oil to freeze?

 

Will need to check what lows I can get on my freezer. May have to source out an industrial freezer. Not sure.

 

Also, would the melting process be a lot more slower to thaw then say ice?

 

thanks

 

thanks inow

[Klaynos]

I suspect crude oil would be harder, because it's quite a complex mix of different oils...

 

If you google hard enough you can find the phase diagram for some cude oils, I did it a few years ago but I recall the search being quite hard.

 

At about -30degC diesel is very very thick but not solid.

[hermanntrude]

you'll probably need the kind of temperatures you'll get with dry ice (-78°C) or even liquid nitrogen (-196°C), and it might still be a bit runny or sticky

[insane_alien]

as it is an organic mixture it won't have a definite freezing point and they're will be a big partially frozen temperature range.

[The Omen]

Thanks for the feedback all,

 

Another question.

 

Where in the world do I go to freeze oil at -50c? it's a small batch, roughly 15-20 litres.

 

I haven't had a look yet, but I'm thinking that industrial refrigeration services may not drop to that level.

 

What about uni science labs or governmental institutions with appropriate facilities?

 

Any help on this would be greatly appreciated.

 

If its possible to do at home, even better.

 

Thanks

[CaptainPanic]

you'll probably need the kind of temperatures you'll get with dry ice (-78°C) or even liquid nitrogen (-196°C), and it might still be a bit runny or sticky

 

CO2 (solid) and nitrogen (liquid) are typically things a university's chemistry lab will have available. Whether they are willing to give you several kilograms of it to cool your 15-20 liters of oil, I don't know. Whether they have facilities to cool that much (15-20 liters), I also don't know.

 

Industrial coolings have no lower limits by the way... how do you think that the liquid nitrogen is made in the first place? It arrives at the university already cooled. Universities generally don't have liquid-nitrogen-machines... just storages.

 

Anyway, I've worked with a cooling machine that could reach -60 deg C. It was just a massive gas compressor, just like your refrigerator has (only bigger). But that's quite an investment for a single experiment.

 

Why are you so determined to freeze your 15-20 liters of oil?

What's the purpose of the experiment? If you're interested to study the temperature where it becomes solid, then you need to cool slowly, so forget about liquid nitrogen.

[insane_alien]

Universities generally don't have liquid-nitrogen-machines

 

mine does

[CaptainPanic]

Woo yay! That's cool

[YT2095]

Woo yay! That's cool

 

yeah, that`s the general idea

[Klaynos]

mine does

 

Mine too... well infact my school of physics does, we sell it to the engineering dept...

 

We also make liquid helium (both 3 and 4)... now THAT is cool...

 

And a couple less cool things that just happen to drop out of the system, most is just vented though as it's too much hassle to collect unless someone specifically needs some...

 

You don't actually make it by traditional cooling, but by a joule-kelvin (http://en.wikipedia.org/wiki/Joule-Thomson_effect) or a similar effect...

 

Some gases wont lower their own temperature from room temperature to allow them to turn to liquid... Like Helium, what you need to do there is cool the He with liquid nitrogen and then pass it through a joule-kelvin system many times...

[iNow]

Some gases wont lower their own temperature from room temperature to allow them to turn to liquid... Like Helium, what you need to do there is cool the He with liquid nitrogen and then pass it through a joule-kelvin system many times...

 

There was a good intro for the novice provided on the program we discussed in the thread below.

 

http://www.scienceforums.net/forum/showthread.php?t=30593&highlight=nova+absolute