GB355212A - Process of refining crude petrol - Google Patents

Abstract

Crude petrol containing phenol is purified by cooling to below -40 DEG C. and removing the precipitated phenols, bases, and colouring, gumming, and associated impurities. The cooling may be in presence of adsorbents, e.g. kieselguhr. The petrol may be fractionally distilled, and only the 170-200 DEG C. fraction cooled, as in this fraction the greater part of the phenols and bases are present; the bases may be removed from the lower-boiling fraction by washing with water; the fractions may then be reunited. In an example, crude petrol from the destructive hydrogenation of coal is distilled, and the 170-200 DEG C. fraction cooled to -55 DEG C.; two layers are formed, the upper conttaining 13 per cent of phenol, the lower 60 per cent; the layers are separated, and treated for the recovery of the phenol, e.g. by extraction with petroleum ether as described in Specification 355,213, [Group IV]. Or the lower layer may be treated in the vapour phase with hydrogen in presence of known catalysts to form hydrocarbons which are blended with the upper layer or with other liquid fuels to form motor spirit. The process is more efficient with petrols containing a large proportion of paraffins than with highly aromatic petrol.ALSO:Crude petrol containing phenols is purified by cooling to below -40 DEG C. and removing the precipitated phenols, bases, &c. The cooling may be in presence of adsorbents, e.g. kieselguhr. The petrol may be fractionally distilled, and only the 170-200 DEG C. fraction cooled, as this fraction contains the greater part of the phenols and bases. In an example, crude petrol from the destructive-hydrogenation of coal is distilled, and the 170-200 DEG C. fraction cooled to -55 DEG C.; 2 layers are formed, the upper containing 13 per cent of phenols, the lower 60 per cent; the layers are separated and treated for the recovery of the phenol, e.g. by extraction with petroleum ether as described in Specification 355,213.