摘要 |
<p>A raw 2,6-xylenol product is purified by melting it, then slowly and uniformly cooling it until at least 60 to 100% is crystallized, with the greater concentration of the impurities being present nearer the surface of the resulting crystals, gradually heating the crystalline solid mass to an elevated temperature no higher than by 0.1 DEG to 5 DEG C. below the solidification temperature of 2,6-xylenol to cause only surface melting of the crystals, thus yielding a molten liquid phase and a solid crystalline phase, the solid phase containing 2,6-xylenol in greater purity than the molten phase.</p> |