摘要 |
<p>A process for purifying solid substances by melting and subsequent resolidification, wherein a melted bath of the solid substance is formed, a roller is placed in the bath so that a first portion of its surface is in contact with the melted substance, and the surface of the roller is cooled to a temperature below the melting point of the solid substance. The cooled roller is rotated in the melted substance to collect a solidified film of the substance on the roller surface. A second portion of the roller surface is passed through a heated zone at a temperature above the melting point of the solid substance, so that the solidified film is remelted and collected in an appliance.</p> |