Abstract: A process for recovering light Fischer-Tropsch hydrocarbons from a rich tail gas produced from a Fischer-Tropsch synthesis operation which comprises: (a) recovering separately from a Fischer-Tropsch synthesis operation a Fischer-Tropsch condensate and a hydrocarbon rich Fischer-Tropsch tail gas; (b) cooling the Fischer-Tropsch condensate and Fischer-Tropsch tail gas; (c) using the cooled Fischer-Tropsch condensate as a lean oil to adsorb at least a portion of the light Fischer-Tropsch hydrocarbons present in the Fischer-Tropsch tail gas, whereby a rich oil mixture comprising Fischer-Tropsch condensate and light Fischer-Tropsch hydrocarbons is formed; and (d) collecting the rich oil mixture.

Abstract: A process for production of paraxylene from a charge containing C7-C9 aromatic hydrocarbons in which a first fraction is enriched to at least 30% weight with paraxylene and this fraction is purified by at least one high-temperature crystallization in at least one crystallization zone. Said first fraction is crystallized in a crystallization zone at high temperature T1 and advantageously between +10 and −25° C., crystals in suspension in a mother liquor are recovered, the crystals are separated from the mother liquor in at least a first separation zone, the crystals obtained are partially melted in at least a zone for partial melting and a suspension of crystals is recovered, the crystals in suspension are separated and washed in at least one separation and washing zone and pure paraxylene crystals and washing liquor are recovered, and pure crystals are optionally completely melted and a liquid stream of melted paraxylene is collected.

Abstract: A process for producing paraxylene of very high purity from a charge containing a mixture of aromatic hydrocarbons having 7 to 9 carbon atoms in which at least a portion of the charge is made to circulate in a zone suited to enrich a first fraction of paraxylene and at least a portion of said first fraction is purified by at least one high-temperature crystallization in at least one crystallization zone, the process being characterized in that said first paraxylene-enriched fraction is crystallized in a crystallization zone comprising at least two crystallization stages (50,70) at high temperature, and advantageously between +10 and -25 .degree. C.The paraxylene enriching zone can be a crystallization at very low temperature, a selective adsorption or a toluene disproportionation zone.

Abstract: A process for production of paraxylene from a charge containing C7-C9 aromatic hydrocarbons in which a first fraction is enriched to at least 30% weight with paraxylene and this fraction is purified by at least one high-temperature crystallization in at least one crystallization zone. Said first fraction is crystallized in a crystallization zone at high temperature T1 and advantageously between +10 and -25.degree. C., crystals in suspension in a mother liquor are recovered, the crystals are separated from the mother liquor in at least a first separation zone, the crystals obtained are partially melted in at least a zone for partial melting and a suspension of crystals is recovered, the crystals in suspension are separated and washed in at least one separation and washing zone and pure paraxylene crystals and washing liquor are recovered, and pure crystals are optionally completely melted and a liquid stream of melted paraxylene is collected.

Abstract: A process for separating paraxylene at very high purity from a charge of xylene isomers, comprising a selective adsorption of a fraction that is rich in paraxylene, at least one high-temperature crystallization of this fraction, and an isomerization of the fraction depleted of paraxylene, recycling the mother liquor to the selective adsorption optionally via a clay treatment followed optionally by a distillation of the treatment effluent, and optionally introducing the mother liquor into a distillation unit, wherein the crystallization can comprise several high-temperature stages.

Abstract: A process is provided for producing high purity benzene and high purity paraxylene from a hydrocarbon feed. In one aspect, the process comprises: (a) reforming a hydrocarbon feed using either a monofunctional catalyst or a bifunctional catalyst to provide one or more reformate streams; (b) fractionating the reformate stream to provide a toluene stream, a benzene stream, and a xylene stream; (c) subjecting the toluene stream to disproportionation; (d) purifying the benzene stream by extraction followed by distillation to provide a high purity benzene product; and (e) purifying the xylene stream by simulated moving bed countercurrent adsorption followed by crystallization to provide a high purity paraxylene product.