| 摘要 |
<p>A re-refining process is described by which high-quality finished lubricating oils are prepared from used waste lubricating and crankcase oils. The used oils are stripped of water and low-boiling contaminants by vacuum distillation and then dissolved in a solvent of 1-butanol, 2-propanol and methylethyl ketone, which precipitates a sludge containing most of the solid and liquid contaminants, unspent additves, and oxidation products present in the used oil. After separating the purified oil-solvent mixture from the sludge and recovering the solvent for recycling, the purified oil is preferably fractional vacuum-distilled, forming lubricating oil distillate fractions which are then decolorized and deodorized to prepare blending stocks. The blending stocks are blended to obtain a lubricating oil base of appropriate viscosity before being mixed with an appropriate additive package to form the finished lubricating oil product. Advantages of the process include recovery of a higher percentage of waste oil, the formation of a by-product sludge that is essentially neutral and thus more environmentally compatible than are the sludges resulting from most other recovery processes, and reduced destruction of the diaromatic and polyaromatic polar materials which impart natural lubricity and oxidation resistance to the oils.</p> |
