| 摘要 |
<p>A method for producing para-xylene from a xylene-containing feedstock, wherein a first fraction is enriched to at least 30 wt.% with para-xylene, and said fraction is purified by means of at least one high-temperature crystallisation step performed in at least one crystallisation zone. Specifically, said first fraction enriched to at least 30 wt.% with para-xylene is crystallised in a crystallisation zone (50) at a high temperature (T1), advantageously between +10 and -25 °C, a suspension of crystals in a mother liquor is recovered, the crystals are separated from the mother liquor in at least a first separation zone (52), the resulting crystals are partially melted in at least one partial melting zone (55), a crystal suspension is recovered, the crystal suspension is separated and washed in at least one separation and washing zone (57), and pure para-xylene crystals and a washing liquor (58) are recovered, whereafter said pure crystals are optionally completely melted (61) and a liquid stream (60) of molten para-xylene is recovered. The mother liquor may be crystallised in a second crystallisation zone at a high temperature (T2) lower than the first (T1), and the second crystals may be partially melted, separated and washed as above.</p> |
