Patent ID: 6664433
Filing Date: 2003-12-16
Classification: A01N,C07C,C10G

Abstract:
A process for purifying an aromatic hydrocarbon comprising:(i) treating an aromatic hydrocarbon containing impurities with an aldehyde selected from the group consisting of formaldehyde and compounds generating formaldehyde in a reaction system, and at least one phenol in the presence an acid catalyst to form oligomers, (ii) distilling or evaporating the mixture of (i) to separate unreacted aromatic hydrocarbon from oligomers, (iii) crystallizing the separated aromatic hydrocarbon, and optionally (iv) washing the crystallized aromatic hydrocarbon with an organic solvent; wherein the proportion of the aldehyde is in the range of 20-40 parts by weight, and at least one phenol is in the range of 30-60 parts by weight, per 100 parts by weight of the aromatic hydrocarbon.