Abstract: A steam-cracking unit comprises at least one multitube quenching exchanger, equipped with a non-obstructive impact separator for preventing the erosion of the tubular input plate. The impact separator is at least 50% opaque when viewed from transfer pipe. It is arranged inside of an input cone in such a way that there is free passage of at least 40 mm between the periphery of the impact separator and the cone.

Abstract: A continuous pyrolysis and decoking process and apparatus is described for the production of acetylenic compounds, in which hydrocarbons and steam are circulated in at least one tube (31) of a steam cracking reactor (30) and steam is circulated in at least one tube (32) of that reactor. The hydrocarbon effluent and steam then circulate in at least one row (1) of a pyrolysis reactor (40) and the decoking effluent comprising steam circulate in at least one other row (2) of that reactor (4) to effect decoking. A set of valves V1, V2, V11, V12 is used to alternate the pyrolysis step path and the decoking step path. The temperature in the steam cracking furnaces is lower than that in the pyrolysis reactor.

Abstract: A process for thermal pyrolysis of a feedstock containing at least 80% ethane to convert to ethylene at a conversion rate of at least equal 80% by feeding the feedstock into a reaction zone in which heating means are arranged approximately perpendicular to the direction of flow of the feedstock. The temperature of the outlet of the heating zone in the reaction zone is between 880 and 960° C. and the dwell time of the feedstock in the heating zone is between 1005 and 3000 milliseconds.

Abstract: A steam-cracking process includes the injection, at at least one point upstream from a secondary quenching indirect exchanger (4b), of particles with a mean size of between 0.02 and 4 mm, at a velocity speed in the exchanger of 20 to 180 m/s, in sufficient quantity to limit the rise in the output temperature of the effluents from the exchanger to a value that is less than 100° C. per month. At least 70% by weight of the quantity of injected particles is introduced downstream from primary quenching exchangers (4a) and upstream from the inlet to the secondary quenching exchanger. At intervals, decoking of the pyrolysis pipes and primary quenching exchangers is carried out in the presence of air.

Abstract: A steam-cracking unit and a steam-cracking process with controlled injection of solid particles in a quenching exchanger (3) is described. The particles are injected through a single axial injection pipe that is arranged on the axis of input cone (2) of the quenching exchanger, just upstream from an impact separator-diffuser (6) that comprises solid surfaces that are arranged opposite the transfer pipe of the cracked gases toward the exchanger; this impact separator-distributor is located in input cone (2) of the exchanger and is gas-permeable along a number of passages and at least 70% opaque when viewed from the transfer pipe.

Abstract: A continuous pyrolysis and decoking process and apparatus is described for the production of acetylenic compounds, in which hydrocarbons and steam are circulated in at least one tube (31) of a steam cracking reactor (30) and steam is circulated in at least one tube (32) of that reactor. The hydrocarbon effluent and steam then circulate in at least one row (1) of a pyrolysis reactor (40) and the decoking effluent comprising steam circulate in at least one other row (2) of that reactor (4) to effect decoking. A set of valves V1, V2, V11, V12 is used to alternate the pyrolysis step path and the decoking step path. The temperature in the steam cracking furnaces is lower than that in the pyrolysis reactor.

Abstract: A flexible steam cracking process for hydrocarbon feeds comprises injection of particles with an average size of between 0.02 mm and 4 mm, at a circulation rate in indirect transfer line exchangers (4) of 20 to 180 m/s, and in a sufficient quantity to limit the increase in temperature at the outlet to the exchangers (4) to a value of less than 100.degree. C. per month, into at least one point upstream of an indirect transfer line exchanger (4), cracking zone (2) remaining in communication with downstream means (6) for the treatment of cooled effluents. At least 70% by weight of the quantity of injected particles is introduced between the outlet to the cracking zone (2) and the tubes of the indirect transfer line exchanger (4). Chemical decoking is carried out in the tubes of the cracking zone at time intervals of less than 4 months by establishing accelerated coke gasification conditions, for example by injecting compounds which catalyse gasification by steam, or by decoking in air and/or steam.

Abstract: A facility and a process for steam cracking include controlled injection of solid particles into a transfer line exchanger (3). The particles are injected via injection lines, numbering between 1 and 8, just upstream of an impact-diffuser (6) comprising solid surfaces disposed on either side of the line for transfer of the cracked gases to the exchanger; this impact-diffuser is located in the inlet cone (2) of the exchanger, is permeable to the gases via a plurality of passages and at least 70% opaque viewed from the transfer line.

Abstract: A process for the regeneration of a sulfur containing catalysts, wherein the catalyst is stripped of sulfur before the oxychlorination treatment of the regeneration process, typically before the catalyst is sent to the regeneration zone. The process is particularly useful for catalyst employed in hydrocarbon conversions such as dehydrogenation reactions, particularly those which comprise the injection of sulfur and/or at least one sulfur compound before or simultaneously to the introduction of the charge into the first reaction zone.

Abstract: The present invention concerns, in the dehydroisomerization of at least one C.sub.4 -C.sub.5 n-paraffin, preferably n-butane, the use of a catalyst comprising a refractory oxide based support, preferably an alumina, at least one precious metal from group VIII, preferably platinum or palladium, optionally at least one element from group IVB such as titanium or zirconium, preferably titanium, optionally at least one element from the group formed by germanium, tin, lead, rhenium, tungsten and indium, and optionally at least one halogen such as chlorine. The present invention also concerns the regeneration of this catalyst.

Abstract: A steam cracking process and facility is described which comprises injection of erosive powder to effect at least partial decoking of transfer line exchangers without interrupting the steam cracking stream. The powder, preferably injected just upstream of the transfer line exchangers (TLE) (4), is separated from the cracked gases in primary gas/solid separators (5), temporarily stored in receiving drums at a controlled temperature and evacuated to a common powder storage and/or treatment module by pneumatic transfer by means of a relatively low flow of uncondensable gas. The process and facility can be used to collect solid fragments generated by injection of chemical compounds which are catalysts for the gasification of coke by steam.

Abstract: A device for the catalytic dehydrogenation of a C.sub.2+ paraffinic hydrocarbon charge is applicable to the synthesis of methyl tert-butyl ether. Effluent coming from the dehydrogenation reactor and containing olefins and water is cooled in at least one heat exchanger (41), saturated with water in a column (3) and sent to a stripping column (10) where it is at least partly put in contact with a recycled aqueous liquid phase containing a solvent, preferably methanol. The compressed gaseous effluent in which the water is thereby inhibited from freezing by the methanol is cooled in a heat exchanger (13) then separated in separator (8) into olefins and into hydrogen. An aqueous liquid phase with methanol is decanted at (8) and recycled in column (10).

Abstract: A device for catalytic dehydrogenation of a C.sub.2+ paraffinic cut with an improved system for cooling the effluent is applicable, for example, to the synthesis of methyl tert-butyl ether. Liquid charge 12 is evaporated in the calandria of a heat exchanger 13 in the optional presence of at least one part recycled hydrogen 15, then optionally compressed in a compressor 14 before being pre-heated in an exchanger 41 by effluent 1 and introduced into a dehydrogenation reactor 40. The effluent cooled in the tubes of exchanger 13 can be mixed with a cryogenic phase 17 resulting from the isentropic expansion of a hydrogen-rich phase separated in a separator 8, the hydrogen optionally being recycled to the calandria of the heat exchanger. The olefins recovered with the unconverted paraffins are stabilized in a column 20.

Abstract: Continuous process for the skeletal isomerization of n-olefins containing at the most 20 carbon atoms, in the presence of a catalyst essentially constituted by alumina and titanium, in which a charge containing the said n-olefins is made to flow through at least one fluidized bed reaction zone, the catalyst flowing into each reaction zone. The catalyst drawn off from the final reaction zone is passed into a regeneration zone, at the outlet of which it is passed into a zone where it undergoes a steam treatment prior to its reintroduction into the first reaction zone. The process is performed in the presence of steam, so that the catalyst is in contact with 3 to 85 wt. % (based on the catalyst weight) of steam. The water/olefin charge molar ratio in the reaction zone is between 0.1 and 3.

Abstract: The invention concerns an isomerisation process for n-olefins containing at most 20 carbon atoms, consisting of bringing a feed containing the olefins into contact with an alumina based catalyst impregnated with 0.03% to 0.6% by weight of titanium and 0.05% to 5% by weight of an oxide of an element from group IIIA. The process can then be carried out in the presence of a small quantity of steam or it can be carried out in the absence of steam.

Abstract: The invention concerns a process for the skeletal isomerisation of n-olefins containing 4 to 20 carbon atoms, consisting in bringing a feedstock containing the olefins into contact with a catalyst prepared from an alumina-based compound which is treated with a polyoroanosiloxane then heat treated. The quantity of silica introduced is generally between 0.05% and 15% by weight.

Abstract: A process and a device for catalytic dehydrogenation of a C.sub.2+ paraffinic cut with an improved system for cooling the effluent is applicable, for example, to the synthesis of methyl tert-butyl ether. Liquid charge 12 is evaporated in the calandria of a heat exchanger 13 in the optional presence of at least one part recycled hydrogen 15, then optionally compressed in a compressor 14 before being preheated in an exchanger 41 by effluent 1 and introduced into a dehydrogenation reactor 40. The effluent cooled in the tubes of exchanger 13 can be mixed with a cryogenic phase 17 resulting from the isentropic expansion of a hydrogen-rich phase separated in a separator 8, the hydrogen optionally being recycled to the calandria of the heat exchanger. The olefins recovered with the unconverted paraffins are stabilized in a column 20.

Abstract: A process and a device for the catalytic dehydrogenation of a C.sub.2+ paraffinic hydrocarbon charge is applicable to the synthesis of methyl tert-butyl ether. Effluent coming from the dehydrogenation reactor and containing olefins and water is cooled in at least one heat exchanger (41), saturated with water in a column (3) and sent to a stripping column (10) where it is at least partly put in contact with a recycled aqueous liquid phase containing a solvent, preferably methanol. The compressed gaseous effluent in which the water is thereby inhibited from freezing by the methanol is cooled in a heat exchanger (13) then separated in separator (8) into olefins and into hydrogen. An aqueous liquid phase with methanol is decanted at (8) and recycled in column (10).

Abstract: Process for the dehydrogenation of a charge incorporating saturated aliphatic hydrocarbons essentially having 3 to 5 carbon atoms per molecule, in which the charge, previously heated to the reaction temperature and without premixing with the hydrogen, is introduced at the inlet of at least one reactor, where the dehydrogenation reaction is performed in the presence of a catalyst, preferably incorporating a support having at least one oxide of an element chosen from among the groups IIA, IIB, IIIA, IIIB, IVA and IVB of the periodic classification of elements, at least one noble metal from the platinum family, at least one promotor metal and at least one alkali metal or alkaline earth metal.

Abstract: A continuous process for the dehydrogenation of paraffinic and olefinic hydrocarbons in the presence of a catalyst comprises circulating a charge containing said paraffinic hydrocarbons through at least two reactions zones of the moving bed type which are arranged in series, the catalyst flowing successively in each reaction zone. The catalyst which is drawn off from the last reaction zone is sent to a regeneration zone at the exit from which it is reintroduced close to the first reaction zone. The process comprises the injection of sulphur and/or at least one sulphur compound before or simultaneously to the introduction of the charge into the first reaction zone. In accordance with the process, the catalyst which is drawn off from the last reaction zone is sent into a stripping zone wherein the sulphur which it contains is removed before the catalyst is sent to the regeneration zone.