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: The damper coating for shocks produced by a collision, or impacts produced by a shockwave, contains at least one layer of a crushing material (2) intended to cover a surface to be protected, the external layer of the crushing material (2) being, according to the present invention, covered by a skin (4) capable of providing a widening of the area affected by the shock or impact. The skin (4) contains, in particular, several layers (5.sub.1 ; 5.sub.2 ; 5.sub.3) of scales (6.sub.1 ; 6.sub.2 ; 6.sub.3), the scales of one layer being offset in staggered rows with respect to the scales of the following layer and being separated from the neighbouring scales of the same layer or capable of being separated from the latter on the application of the shock or impact. The structure of this damper coating is designed to dampen the impact under a reduced thickness.

Abstract: The invention relates to the process for preparing ethyne by the pyrolysis of ethane by heating the same for a period of time that is less than 0.5 sec in a pyrolysis reactor at a temperature in the range of 950 to 1500.degree. C., using steam as diluent gas in a steam/ethane molar ratio of at most 3.

Abstract: In a process for treating a gas containing hydrogen sulphide and sulphur dioxide, such as Claus plant tail gas, to substantially reduce emission of sulphur vapor in the treated gases, the process a characterized in that the gas is brought into contact with a solvent (5) in at least one gas-liquid reactor-contactor (2) and a gas (20) is recovered which is sent to a second reactor (102) where it is brought into contact with solvent (105), the solvent (105) being cooled by suitable means (190), to separate a portion of the sulphur from the solvent. The resultant solvent depleted in sulphur, contacts the gas (20) from the first reactor (2). The gas (120) from the second reactor is highly depleted in sulphur vapor. At least one of the reactors contains a catalyst. The solvent may be insoluble in water, e.g. dodecane, tridecane, naphtha, or soluble in water, e.g. glycerol, thiodiglycol, cyclohexanedimethylethanol, or an acid ester. The catalyst may comprise, e.g.

Abstract: The invention relates to a method for characterizing a hydrocarbon reservoir comprising a gas cap (1) and an oil zone (2) with respectively Scwg and Scwo as the water saturation in each zone. The zone is invaded by gas either by gas injection, gas cap expansion or because of evolution of dissolved gases. In the method, the decrease in the initial water saturation Scwo in oil zone (6) during the displacement thereof by the gas is taken into account, the decrease being gradual down to Scwg which is distinctly below Scwo.

Abstract: The invention concerns a process for improving the pour point of a feed comprising paraffins containing more than 10 carbon atoms, in which process the feed to be treated is brought into contact with a catalyst comprising NU-86 zeolite, preferably dealuminated, and at least one hydro-dehydrogenating element, at a temperature which is in the range 170.degree. C. to 500.degree. C., a pressure in the range 1 to 250 bar and an hourly space velocity in the range 0.05 to 100 h.sup.-1, in the presence of hydrogen in a proportion of 50 to 2000 l/l of feed. The product from heavy feeds is fractionated to produce at least one cut including at least one middle distillate with a reduced pour point, and a residue including oil bases with a reduced pour point and a high viscosity index.

Abstract: To continuously produce and separate high purity p-xylene from a C.sub.8 aromatic hydrocarbon charge, successive use is made in combination of (1) a stage of separating low-purity p-xylene (75 to 98%) by simulated moving bed adsorption chromatography; (2) a stage of purifying and washing the low-purity p-xylene by recrystallization (-25 to +10.degree. C.); (3) a stage of catalytic isomerization of the charge which has been p-xylene-depleted by the separating stage (1); and recovering an isomerate which is then recycled to the charge. The solvent for desorption in stage (1) and washing in stage (2) is advantageously toluene.

Abstract: The invention concerns the use of a catalyst for the dismutation of alkylaromatic hydrocarbons, preferably for the dismutation of toluene to produce benzene and xylenes, and/or for the transalkylation of alkylaromatic hydrocarbons, preferably for the transalkylation of toluene and trimethylbenzenes to produce xylenes. The catalyst is a composite comprising at least one zeolite with structure type mazzite, at least partially in its acid form, at least one zeolite with structure type mordenite, at least partially in its acid form, at least one matrix and, optionally, at least one element selected from the group formed by groups IB and VIII of the periodic classification of the elements.

Abstract: A process for the fed batch production of a sophorolipid composition is described, in which culturing takes place of at least one Candida bombicola strain in a culture medium incorporating a sugar and a nitrogen source and said cultured strain is exposed in a reaction zone to a supply of an appropriate substrate under adequate aeration, temperature and pH conditions and at least once the following sequence is performed: a) the strain is continuously supplied with substrate at a supply rate in the reaction zone between 0.

Abstract: A supported catalyst with rhenium and also containing aluminium introduced by a compound of the formula (OR).sub.qAlR'.sub.r with R being a hydrocarbyl residue with from 1 to 40 carbon atoms, R' being an alkyl residue with from 1 to 20 carbon atoms, and with q and r equal to 1 or 2 with q+r=3. A process for the preparation of a catalyst comprising impregnating a compound of rhenium on a porous support formed by refractory oxides and/or alumino-silicates of an acid, neutral or basic nature, roasting at a temperature of form 200 to 950.degree. C. and impregnating with said aluminium compound. The catalyst is used for the metathesis of olefins.

Abstract: Improved process for implementing the Diels-Alder reaction that consists in using reagents in the presence of at least one liquid salt of general formula Q.sup.+ A.sup.-, in which Q.sup.+ represents a quaternary ammonium and/or phosphonium and A.sup.- represents an anion and optionally at least one Lewis acid. The anion is preferably selected from the group that is formed by tetrafluoroborate, hexafluorophosphate, hexafluoroantimonate, hexafluoroarsenate, perfluoroalkylsulfonate, fluorosulfonate or else dichlorocuprate, tetrachloroborate, tetrachloroaluminate, and trichlorozincate. At the end of the reaction, the organic phase is separated, and the polar phase is reused.