I would like to ask this,dissolved particulates would have what affect on lube oils? I could see it being an issue if it made the oil acidic or broke down the lubricating properties but causing more wear I do not see happening if the particulates are heavier than the oil even in a liquid state then heating and cooling the oil over a period of time would settle the particulates to the bottom however if it is bonded to the oil I would think you would damage the lubricating properties by thinning it however you may try diluting it with clean oil and reusing it. If you try using a chemical to remove the bond you may damage the lubricating properties of the oil if your not certain you can certainly use that uber clean oil as fuel.
The problem here is understanding the difference between suspension of particles and dissolution.
wiki said:
Dissolution is the process by which a solute forms a
solution in a
solvent. The solute, in the case of solids, has its crystalline structure disintegrated as separate ions, atoms, and molecules form. For liquids and gases, the molecules must be adaptable with those of the solvent for a solution to form. The outcome of the process of dissolution (the amount dissolved at equilibrium, i.e., the
solubility) is governed by the
thermodynamic energies involved, such as the
heat of solution and
entropy of solution, but the dissolution itself (a kinetic process) is not.
Whereas, particle suspension is where the particles still exist, they are just floating in the medium, and often too small to filter out. Abrasive particles floating in a medium can be a source of abrasion, although, sub-micron particles might be so small that they pose no risk of abrasion.
As you mentioned it, dissolved particles, which are, by definition, no longer particles, might cause, in this case, lubricating oil to become acidic, and acidic lubricating oil can cause corrosion.
However, we have 2 paths of discussion here: 1] waste oils used as fuel, and 2] the recycling of lubricating oils as lubricating oils.
1] The recycling of lubricating oils as fuel requires addressing the dissolved carbon and metals, because they produce ash and coke during combustion. It is this ash and coke that can lead to injector coking and increased wear of engine parts. Differential solubility, and distillation are ways to remove those dissolved carbon and metals from lubricating oils used as fuel. Distillation is another way to do it.
2] The recycling of lubricating oils as lubricating oils is another issue. The myth is "oil does not get warn out, it just gets dirty." Well, it does wears out.
How lubricating oils "wears out," is hydro carbons are prone to polymerization under oxidation, time, pressure and temperature. Polymerized lubricating oils accumulate long-chain hydrocarbons that tend to melt at 160F and above. The engine coolant in most internal combustion engines is 160F. What happens is polymerized lubricating oils accumulate in the coldest spots in the lubricating cycle, which is the oil pan and valve cover. Eventually polymerized lubricating oils will accumulate on the valves and interfere with valve performance.
Distillation will remove both dissolved carbon and metals as well as polymerized hydrocarbons. Therefore distillation is a superior method of recycling lubricating oils for any purpose.
