Abstract: Catalytic process for metathesis of olefins in the presence of a catalyst and a stabilizing agent that is injected into the reaction medium. Application in particular to rebalancing between one another the light olefins that are obtained from steam cracking or catalytic cracking (FCC), such as ethylene, propylene, butenes or pentenes.

Abstract: Catalytic process for metathesis of olefins in the presence of a catalyst and a stabilizing agent that is injected into the reaction medium. Application in particular to rebalancing between one another the light olefins that are obtained from steam cracking or catalytic cracking (FCC), such as ethylene, propylene, butenes or pentenes.

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 device for crystallization of a component from a liquid mixture comprising a chamber, a first conduit connected to said chamber for supplying said mixture, a second conduit connected to and in connection with said chamber for introducing cold gas, a third conduit for withdrawing warmed gas from said crystallizer, a turbo-expander for cooling gas withdrawn from said chamber, and a fourth conduit Icading from the turbo-expander to said chamber. The device has particular application for the crystallization of paraxylene.

Abstract: A process for eliminating at least pollutants including polar compounds present in a first fluid, with said first fluid sent to a subsequent treatment, e.g., an etherification process: a) the first fluid containing pollutants is contacted with an auxiliary fluid such as a vapor phase, under operating conditions that are selected so as to obtain, at the end of this first stage, said first fluid that is purified and freed of, for the most part, pollutants, and a vapor phase that is loaded with pollutants, said vapor phase being produced during one phase of the process, and b) at least a portion of said first purified fluid is recycled to a subsequent treatment stage.

Abstract: The invention concerns a petroleum product and a process for the production of a petroleum product which can form part of a blend for an internal combustion engine fuel, the process comprisinga) hydrotreating a hydrocarbon feedstock at a partial pressure of hydrogen at the reactor outlet of about 0.5 MPa to about 6 MPa,b) separating a product (P) from step a) into a product (P1) with a final boiling point of about 300.degree. C. and a product (P2) with an initial boiling point greater than the final boiling point of product (P1),c) performing a liquid-liquid extraction with a solvent (S1), to produce an extract (E1) and a raffinate (R1) from product (P2),d) recovering solvent (S1) from raffinate (R1) to produce a product (Q1), depleted in solvent (S1), which has improved qualities and contains less than 500 ppm by weight of sulphur.

Abstract: Device and process for crystallizing a component, e.g.

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: The invention concerns a reactive distillation process comprising a distillation zone, associated with a reaction zone which is at least in part internal to said distillation zone and comprises at least one catalytic bed in which the feed is transformed in the presence of a catalyst and at least one gas stream containing hydrogen, characterized in that each catalytic bed in the internal portion of said reaction zone is traversed by said gas stream and liquid in ascending co-current mode. The invention particularly concerns selective hydrogenation processes for light unsaturated hydrocarbons, mainly any olefins and benzene, comprised in a mixture, the major portion of which is constituted by hydrocarbons containing at least five carbon atoms per molecule.

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: Para-xylene is produced from a paraselective toluene disproportionation reactor, effluent (3) is distilled to eliminate toluene and benzene in at least 2 distillation columns (C1), (C2), and the xylenes (8) are crystallized at least once (10) at between +10.degree. C. and -30.degree. C. The separated mother liquor (14) is adsorbed on a zeolitic sieve in the presence of toluene in a simulated moving bed (15). This latter produces a raffinate (16) containing toluene which is depleted in para-xylene which is distilled in a distillation column (C4), and an extract which is enriched in para-xylene and contains toluene, which is recycled to columns (C1, C2). The para-xylene crystals are purified by washing with toluene and distillation or by partial melting (30) followed by washing with molten high purity para-xylene.

Abstract: For the treatment of a feed comprising a major portion of olefinic hydrocarbons containing 4 carbon atoms per molecule, including isobutene, 1-butene and 2-butenes in a ratio which substantially corresponds to the thermodynamic equilibrium, in which the feed is treated in a distillation zone comprising a stripping zone and a rectification zone associated with at least one hydroisomerization reaction zone, the hydroisomerization reaction zone being at least partially internal to the distillation zone and comprising at least one catalytic bed, in which hydroisomerization of at least a portion of 1-butene is carried out in the presence of a hydroisomerization catalyst and at least one gas stream comprising hydrogen, such that an effluent rich in isobutene leaves the distillation zone overhead and an effluent rich in 2-butenes leaves the bottom, the process being characterized in that each catalytic bed in the internal portion of the hydroisomerization zone is traversed by an ascending co-current of the gas strea

Abstract: A process for treating a feed comprising C.sub.5.sup.+ hydrocarbons and comprising at least one unsaturated C.sub.6.sup.+ compound including benzene, is such that the feed is treated in a distillation zone, associated with a hydrogenation zone, comprising at least one catalytic bed, in which the hydrogenation is carried out of unsaturated C.sub.6.sup.+ compounds contained in the feed, and whereof a charge for the hydrogenation step is removed at the height of a removal level and represents at least part of the liquid flowing in the distillation zone, and the effluent from the hydrogenation reaction zone is at least in part reintroduced into the distillation zone to ensure continuity of the distillation operation, the effluents at the top and bottom on the distillation zone being very depleted of unsaturated C.sub.6.sup.+ compounds. The effluent drawn off from the top of the distillation zone is treated in a zone for the isomerisation of C.sub.5 and/or C.sub.6 paraffins.

Abstract: The invention concerns a petroleum product and a process for the production of a petroleum product which can form part of a blend for an internal combustion engine fuel, the process comprisinga) hydrotreating a hydrocarbon feedstock at a partial pressure of hydrogen at the reactor outlet of about 0.5 MPa to about 6 MPa,b) separating a product (P) from step a) into a product (P1) with a final boiling point of about 300.degree. C. and a product (P2) with an initial boiling point greater than the final boiling point of product (P1),c) performing a liquid-liquid extraction with a solvent (S1), to produce an extract (E1) and a raffinate (R1) from product (P2),d) recovering solvent (S1) from raffinate (R1) to produce a product (Q1), depleted in solvent (S1), which has improved qualities and contains less than 500 ppm by weight of sulphur.

Abstract: The invention concerns a reactive distillation apparatus comprising a distillation zone, associated with a reaction zone which is at least in part internal to said distillation zone and comprises at least one catalytic bed in which the feed is transformed in the presence of a catalyst and at least one gas stream containing hydrogen, characterized in that each catalytic bed in the internal portion of said reaction zone is traversed by said gas stream and liquid in ascending co-current mode.

Abstract: Para-xylene is produced from a paraselective toluene disproportionation reactor, effluent is distilled to eliminate toluene and benzene in at least 2 distillation columns, and the xylenes are crystallized at least once at between +10.degree. C. and -30.degree. C. The separated mother liquor is adsorbed on a zeolitic sieve in the presence of toluene in a simulated moving bed. This latter produces a raffinate containing toluene which is depleted in para-xylene which is distilled in a distillation column, and an extract which is enriched in para-xylene and contains toluene, which is recycled. The para-xylene crystals are purified by washing with toluene and distillation or by partial melting followed by washing with molten high purity para-xylene.

Abstract: The invention is concerned with a process for treating a charge of which the major part is constituted by hydrocarbons comprising at least 5 carbon atoms per molecule and comprising at least one unsaturated compound comprising at the most six carbon atoms per molecule including benzene, such that said charge is treated in a distillation zone, comprising a drainage zone and a stripping zone, associated with a hydrogenation reaction zone, comprising at least one catalytic bed, in which hydrogenation is carried out of at least part of the unsaturated compounds comprising at the most six carbon atoms per molecule and contained in the charge, the charge of said reaction zone being removed at the height of a removal level and representing at least a part of the liquid flowing in the distillation zone, the effluent of the reaction zone being at least partly reintroduced into the distillation zone, in such a way as to ensure the continuity of the distillation operation and in such a way as to remove from the top of t

Abstract: A fuel for internal combustion engines having an improved cetane index and lower sulfur content is obtained from a hydrocarbon charge, by a process comprising a step (a) for distillation (D1) in which a bottom product (Q1) is obtained via a line 3 and in which a top product (T1) is obtained via a line 2, a step (b) of liquid/liquid extraction (LE) using a solvent (S1) to obtain a raffinate (R1), (line 5) an extract from which product (Q1) is obtained (line 6), a step c) separating (D2) the raffinate (R1) enabling a product (Q2) to be obtained via line 7, which product has a low solvent (S1) content, and a step (d) of hydrotreatment (HDS) in which the mixture of the products (T1) and (Q2) are subjected to hydrotreatment with a hydrogen partial pressure of less than 10 megapascals, to obtain a product (P) (line 9) which has improved qualities and which contains less than 500 ppm by weight sulphur.

Abstract: Process for the production of tertiary ethers (MTBE, ETBE, TAME, ETAE) in which a hydrocarbon cut (1) containing four or five carbon atoms is reacted with methanol or ethanol (2, 3) in a reactor and recovering ethers (11) and a distillate (10) after distillation (C.sub.I). The distillate undergoes a first extractive distillation step in column (C.sub.11) in the presence of a solvent (27) which is selective towards olefinic hydrocarbons. A saturated hydrocarbon-rich overhead fraction (15) is recovered along with a bottom fraction (18) which is rich in olefins, solvent and alcohol. The olefins (20) are separated from the solvent and alcohol (24) in a second extractive distillation step (C.sub.III). The olefins are isomerised in a skeletal isomerisation reactor (5) and the isomerate is recycled (2) to reactor (6). The alcohol and solvent are separated in a stripping column (C.sub.IV). Alcohol (26) is recycled to the synthesis reactor (6) while the solvent (27) is recycled to C.sub.II.