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Carbon Chains in Petroleum Products
The different chain lengths have progressively higher boiling points, so they can be separated out by
distillation. This is what happens in an oil refinery -- crude oil is heated and the different chains are pulled out by their vaporization temperatures. (See
How Oil Refining Works for details.)
The chains in the C[SIZE=-2]5[/SIZE], C[SIZE=-2]6[/SIZE] and C[SIZE=-2]7[/SIZE] range are all very light, easily vaporized, clear liquids called
naphthas. They are used as solvents --
dry cleaning fluids can be made from these liquids, as well as paint solvents and other quick-drying products.
The chains from C[SIZE=-2]7[/SIZE]H[SIZE=-2]16[/SIZE] through C[SIZE=-2]11[/SIZE]H[SIZE=-2]24[/SIZE] are blended together and used for
gasoline. All of them vaporize at temperatures below the boiling point of water. That's why if you spill gasoline on the ground it evaporates very quickly.
Next is
kerosene, in the C[SIZE=-2]12[/SIZE] to C[SIZE=-2]15[/SIZE] range, followed by diesel fuel and heavier fuel oils (like heating oil for houses).
Next come the
lubricating oils. These oils no longer vaporize in any way at normal temperatures. For example, engine oil can run all day at 250 degrees F (121 degrees C) without vaporizing at all. Oils go from very light (like 3-in-1 oil) through various thicknesses of motor oil through very thick
gear oils and then semi-solid greases. Vasoline falls in there as well.
Chains above the C[SIZE=-2]20[/SIZE] range form solids, starting with paraffin wax, then tar and finally asphaltic bitumen, which is used to make asphalt roads.
All of these different substances come from crude oil. The only difference is the length of the carbon chains!
Now, If I were given a barrel of kerosine and I ran used motor oil regularly, I would use the kerosine to thin my UMO. How much? I personally add 5-10 gals of diesel or kero to 40 gals of UMO. Been doing this for quite some time. never had an issue yet.