| 摘要 |
<p>Lubricating oils are dewaxed by (a) treating in a first stage with a solvent having a low b.p. in order to remove the major part of the paraffin waxes including the isoparaffins, and (b) treating the normal waves remaining in the oil with a saturated urea soln., in order to provide an oil with a low freezing point, and a wax with a low oil content. Gives lubricating oils entirely free of paraffins, and waxes entirely free of oil. The process and apparatus are cheap, as low pressures are used, and external cooling sources, such as ammonia, are avoided.</p> |
