| 摘要 |
<p>Paraffin wax-contg. petroleum fractions are dewaxed by (a) rapidly cooling the fraction by injecting cold dewaxing solvent into it in a number of stages, so that in each stage immediate cooling is obtd., (b) uninterruptedly stirring each of the stages, drawing off a mixture of paraffin wax and solvent with a temp. of -29 to +4 degrees C, (d) separating crude paraffin wax from this mixture, (e) mixing the crude paraffin wax with frech solvent at a temp. of 4-27 degrees C, and (f) separating high melting paraffin wax from this mixture. A paraffin wax of excellent quality, which contains practically no oil, is obtd. in a high yield. This wax can be easily filtered, and does not deposit on the surfaces of the appts.</p> |
