| 摘要 |
<p>'Brightstock' for use as cylinder lubricant or oil additive is prepd. by partially de-waxing vacuum residue with liquid propane, refining the product, in a single or multistage process using a catalyst and in presence of H2, freeing the 'brighstock' from light and middle fractions, peforming a solvent deparaffination and finally after-refining with active earth or with H2.</p> |
