Abstract: A process for converting hydrocarbons in the presence of a catalyst is described that is carried out in a three-phase reactor in which the liquid Peclet number is in the range 0 (excluded) to about 10, with a superficial gas velocity Ug that is preferably less than 35 cm.s−1, to encourage gas transfer into the liquid phase and avoid too much attrition of the catalyst grains.

Abstract: A circuit (200) for protection against voltage or current spikes receives an initial clock signal (CI) and transmits at least one resultant clock signal (CN1, CN2, CP1, CP2) to a downstream circuit. This resultant clock signal is inactive if a random voltage or current spike appears upstream. This averts the possibility of disturbing the operation of the downstream circuit. Application to the protection of clock circuits for integrated circuits.

Abstract: A process is described for carrying out olefin oligomerisation in two catalysis steps of different types, using an organic feed containing at least one olefin. The cut to be treated, containing at least one olefin (Cn), is introduced into a first reaction zone where, in a first step, it undergoes catalytic oligomerisation either of the homogeneous liquid phase type, or of the heterogeneous type with a solid support. The effluent produced is generally sent to a heat exchanger traversed by a cold liquid, the effluent thus being cooled before being sent to a second reaction zone where it undergoes catalytic oligomerisation in a liquid—liquid two-phase medium, the invention being characterized in that at least an ethylenic hydrocarbon containing 3 to 5 carbon atoms per molecule is added to the inlet to the second reaction zone.

Abstract: A process for carrying out a reaction on an organic feed, for example dimerization, co-dimerization, oligomerization or metathesis of olefins, as described in which the catalyst is a catalytic metal compound dissolved in a non-aqueous ionic medium which is not or is only slightly miscible with hydrocarbons. The reaction is carried out in a system comprising at least two treatment loops each comprising at least one reaction zone and at least one zone for separating the organic and polar phases between which the polar medium containing the catalytic metal compound, and the organic phase circulate. Fresh polar phase is injected into the second loop and used polar phase is eliminated from the first loop. The hydrocarbon to be transformed is injected into the first loop and the products are withdrawn from the second loop. The invention also concerns a unit for carrying out the process.

Abstract: The present invention provides a catalyst and a process for metathesis of olefinic C4 cuts. The catalyst contains rhenium, caesium and delta alumina. The preferred catalyst contains at least one rhenium compound deposited on a support principally composed of alumina, treated at a temperature of more than 750° C., and modified by at least one caesium compound. Thus the duration of the cycle between two regeneration operations is substantially increased. Application to a process for the production of propylene from an olefinic C4 cut in three steps: selective hydrogenation of butadiene with isomerisation of 1-butene to 2-butene, separation by distillation of the major portion of the isobutene, and metathesis of the cut rich in 2-butene with ethylene.

Abstract: A process for synthesising hydrocarbons by reacting a mixture comprising at least carbon monoxide and hydrogen in the presence of a catalyst is carried out in a three-phase reactor in which the liquid Peclet number is in the range 0 (excluded) to about 10, with a superficial gas velocity Ug that is preferably less than 35 cm.s−1, to encourage gas transfer into the liquid phase and avoid too much attrition of the catalyst grains.

Abstract: The invention concerns a method for converting hydrocarbons in the presence of a catalyst carried out in a three-phase reactor and wherein the liquid Peclet number ranges between 0 (excluded) and about 10, and the gas surface speed Ug is preferably less than 35 sm.s−1, so as to promote the transfer, of gas into the liquid phase and avoid too much attrition of the catalyst grains.

Abstract: A micro-pipeline type asynchronous circuit and a method for detecting and correcting soft error. The asynchronous circuit records in a first recording unit a signal output by a calculation unit and then records in a second recording unit the same signal delayed by at least the duration of the pulse of a soft error. The recorded signals then are compared in a comparer circuit. If they are identical, no soft error has been detected and the output signal is recorded after another delay that is longer than the pulse duration of the soft error, and a request signal is transmitted to a control unit of a next logic stage with a delay twice as long as the pulse duration of a soft error.

Abstract: The present invention provides a catalyst and a process for metathesis of olefinic C4 cuts. The catalyst contains rhenium, caesium and delta alumina. The preferred catalyst contains at least one rhenium compound deposited on a support principally composed of alumina, treated at a temperature of more than 750° C., and modified by at least one caesium compound. Thus the duration of the cycle between two regeneration operations is substantially increased. Application to a process for the production of propylene from an olefinic C4 cut in three steps: selective hydrogenation of butadiene with isomerisation of 1-butene to 2-butene, separation by distillation of the major portion of the isobutene, and metathesis of the cut rich in 2-butene with ethylene.

Abstract: A process is described for carrying out olefin oligomerisation in two catalysis steps of different types, using an organic feed containing at least one olefin. The cut to be treated, containing at least one olefin (Cn), is introduced into a first reaction zone where, in a first step, it undergoes catalytic oligomerisation either of the homogeneous liquid phase type, or of the heterogeneous type with a solid support. The effluent produced is generally sent to a heat exchanger traversed by a cold liquid, the effluent thus being cooled before being sent to a second reaction zone where it undergoes catalytic oligomerisation in a liquid-liquid two-phase medium, the invention being characterized in that at least an ethylenic hydrocarbon containing 3 to 5 carbon atoms per molecule is added to the inlet to the second reaction zone.

Abstract: A micro-pipeline type asynchronous circuit and a method for detecting and correcting soft error. The asynchronous circuit records in a first recording unit a signal output by a calculation unit and then records in a second recording unit the same signal delayed by at least the duration of the pulse of a soft error. The recorded signals then are compared in a comparer circuit. If they are identical, no soft error has been detected and the output signal is recorded after another delay that is longer than the pulse duration of the soft error, and a request signal is transmitted to a control unit of a next logic stage with a delay twice as long as the pulse duration of a soft error.

Abstract: A process for carrying out a reaction on an organic feed, for example dimerization, co-dimerization, oligomerization or metathesis of olefins, as described in which the catalyst is a catalytic metal compound dissolved in a non-aqueous ionic medium which is not or is only slightly miscible with hydrocarbons. The reaction is carried out in a system comprising at least two treatment loops each comprising at least one reaction zone and at least one zone for separating the organic and polar phases between which the polar medium containing the catalytic metal compound, and the organic phase circulate. Fresh polar phase is injected into the second loop and used polar phase is eliminated from the first loop. The hydrocarbon to be transformed is injected into the first loop and the products are withdrawn from the second loop. The invention also concerns a unit for carrying out the process.

Abstract: The present invention relates to a process for continuous metathesis or disproportionation of olefins, comprising at least 2 phases, a reaction phase a) carried out in a zone comprising at least one reactor containing at least one fixed bed of catalyst and a regeneration phase b) carried out in a zone comprising at least one reactor containing at least one fixed bed of catalyst, characterized in that at least one reactor passes from one phase to the other in alternation. In FIG. 1, the feed containing olefins traverses reactor R1 in riser mode. The feed to be treated containing olefins is introduced into reactor R1 via line 1a. In this reactor, the olefins contained in the feed undergo metathesis or disproportionation, then the effluent leaves the circuit via line 11. Simultaneously, reactor R2 is placed in catalyst regeneration phase, the different regeneration gases are introduced into reactor R2 via line 2b and leave this reactor via line 2c.

Abstract: The present invention provides a catalyst and a process for metathesis of olefinic C4 cuts. The catalyst contains rhenium, cesium and delta alumina. The preferred catalyst contains at least one rhenium compound deposited on a support principally composed of alumina, treated at a temperature of more than 750° C., and modified by at least one cesium compound. With the use of the catalyst, the duration of the cycle between two regeneration operations can be substantially increased. The catalyst is suitable for use in a process for production of propylene from an olefinic C4 cut in three steps: (1) selective hydrogenation of butadiene with isomerisation of 1-butene to 2-butene, (2) separation by distillation of the major portion of the isobutene, and (3) metathesis of the cut rich in 2-butene with ethylene.

Abstract: A process for carrying out a reaction on an organic feed (for example dimerisation, co-dimerisation, oligomerisation or metathesis of olefins) is described in which the catalyst is a catalytic metal compound dissolved in a non-aqueous ionic medium which is not or is only slightly miscible with hydrocarbons. The reaction is carried out in a system comprising at least two treatment loops each comprising at least one reaction zone and at least one zone for separating the organic and polar phases between which the polar medium containing the catalytic metal compound, and the organic phase circulate, in a counter-current, Fresh polar phase is injected into the second loop and used polar phase is eliminated from the first loop. The hydrocarbon to be transformed is injected into the first loop and the products are withdrawn from the second loop. The invention also concerns a unit for carrying out the process.

Abstract: For obtaining butene-1 from butene-2, a charge containing at least one of the isomers of butene-2 is introduced into a distillation zone linked to a hydro-isomerization zone. Part of the effluent from the bottom of the distillation column is removed from the distillation zone, heated in a heat exchanger and passed into an external hydro-isomerization zone. The hydro-isomerization effluent is removed from the hydro-isomerization zone, cooled in a heat exchanger, and then reintroduced into the distillation zone. Effluent containing butene-1 is withdrawn from the top of the column of the distillation zone.

Abstract: An acetal, wherein the acetal is 2,2-di(tetrahydrofurfuryloxy)propane as well as processed for producing the acetal and methods of using the acetal.

Abstract: The present invention provides a process for converting olefinic C5 cuts by metathesis using an improved catalyst containing rhenium, cesium, and delta alumina. The preferred catalysts contains at least one rhenium compound deposited on a support principally composed of alumina, treated at a temperature of more than 750° C., and modified by at least one cesium compound. Thus the duration of the cycle between two regeneration operations is substantially increased.

Abstract: A process for producing light alpha olefins by ethylene oligomerisation in contact with a catalyst produced by mixing a zirconium compound with an organic compound selected from the group formed by acetals and ketals, with an aluminum hydrocarbyl compound selected from the group formed by chlorine-containing or bromine-containing aluminum hydrocarbyl compounds and with an aluminum hydrocarbyl compound selected from tris-(hydrocarbyl)-aluminum compounds.

Abstract: A process for separating at least two liquid phases which are at least partially non miscible is characterized in that after reacting, a polyphase effluent is settled in at least two distinct settling zones arranged in parallel, each of these settling zones containing at least one settler. The feed to be treated is sent to reactor R via a means for circulating fluids P via line 1. The effluent leaves the reactor via line 2 and is separated into two fractions. One fraction is sent to a settling zone a) via line 3; the other fraction is sent to a settling zone b) via line 4. The heavy phase from settling zone a) is sent to the reactor via line 7 and the heavy phase of the settling zone b) is sent to the reactor via line 6. The light phase from settling zone a) is sent to line 8, and rejoins fresh feed supply line 1. The light phase from settling zone b) is evacuated from the circuit via line 5.