Abstract: The polymerization process is carried out starting from a monomer that is introduced via pipe (1) and a comonomer that is introduced via pipe (2); the comonomer that is used, which is an alpha-olefin, is introduced into polymerization reactor P in the form of an approximately pure compound. The polymerization effluent is then separated in separator S1 into two fractions: a heavy fraction that is evacuated via pipe (5) and that contains at least one polymer, and a light fraction that is evacuated via pipe (4) and that comprises the monomer that has not reacted, the comonomer that has not reacted, as well as isomers of this comonomer. At least a portion of the light fraction is then treated during an ethenolysis stage E in the presence of an addition of fresh ethylene that is introduced via line (9). The effluent that is produced in the ethenolysis stage is subjected to at least two separations in separation train S2.

Abstract: For obtaining of improved purity of light alpha olefines produced by oligomerization of ethylene, the ethylene is placed in contact with a catalyst obtained by mixture of a zirconium compound with an organic compound selected from the class of acetals and ketals and with a chlorinated or brominated aluminium hydrocarbyl compound, and that the raw oligomerization effluent is firstly treated with an amine, then subjected to vaporization so as to collect the alpha olefines in the vaporized fraction.

Abstract: The invention concerns an improved process for the conversion of ethylene into but-1-ene, wherein the ethylene is brought into contact with a catalyst obtained by the interaction of an alkyl titanate, possibly mixed with an ether, with a compound of aluminium of the formula AlR.sub.3 or AlR.sub.2 H, and in the presence of an additive formed by at least one polyethylene glycol and/or one of its derivatives such as a monoether or a monoester of polyethylene glycol.

Abstract: Process for oligomerizing ethylene into light alpha olefins, mainly 1-butene, 1-hexene, 1-octene and 1-decene, in which the ethylene is contacted with a catalyst obtained by mixing a zirconium compound with an organic compound chosen from within the class of acetals and ketals and with a chlorine or bromine-containing compound of aluminium hydrocarbyl.

Abstract: Process for oligomerizing ethylene into light alpha olefins, mainly 1-butene, 1-hexene, 1-octene and 1-decene, in which the ethylene is contacted with a catalyst obtained by mixing a zirconium compound with an organic compound chosen from within the class of acetals and ketals and with a chlorine or bromine-containing compound of aluminum hydrocarbyl.

Abstract: Process for the catalytic conversion of a charge incorporating at least one oxygen compound such as methanol, into olefinic hydrocarbons having 2 to 4 carbon atoms. Conversion takes place in a reactor (100), into which the charge is introduced by the pipe (20), the catalytic solid by the pipe (30) and the solid entrainment gas by the pipe (40), the reactor being connected by a pipe (1) to a co-current cyclone separator (S) making it possible to separate a solid phase from a gaseous phase containing the conversion products, which is recovered by the pipe (4). The solid phase is fed by the pipe (9) to a regenerator (R), in which the catalytic particles are at least partly regenerated before being returned by the pipe (80), connected to the pipe (30), to the reactor (100).

Abstract: Process for the conversion of ethylene into light alpha olefins, mainly 1-butene, 1-hexene and 1-octene, in which the ethylene is contacted with a catalyst obtained by reacting a performed mixture of alkyl zirconate and ether with a chlorine or bromine-containing aluminum compound.

Abstract: The conversion of a charge comprising at least one oxygen compound is performed in a reactor C, into which the charge is introduced by the pipe (11), the solid catalytic particles forming the dense phase D1 by the pipe (14) and the solid entrainment gas by the pipe (12). The reactor is connected by a pipe (1) to a cocurrent cyclone separator-mixer (MS) making it possible to separate a solid phase from a gaseous phase containing the conversion products recovered by the pipe (4'), while carrying out a quenching of said gaseous phase by a product M2 introduced by the pipe (3). The phase D1 is fed by the pipe (7) to a regenerator R before being returned by the pipe (13) into the reactor C. The mixture of the gaseous phase and the product M2 is separated in a separator and the product M2, optionally after cooling, is recycled to the mixer-separator (MS).

Abstract: A process for producing organolanthanides by reaction of a rare-earth metal with an unsaturated compound in an ether medium, the resultant compounds and the use of these compounds in organic synthesis and for catalysis is disclosed. The process is conducted at -80.degree. to +100.degree. C., in the absence of oxygen and any compound having active protons. The resultant compounds are useful as catalysts, e.g., in the hydrogenation of olefins and diolefins and in the polymerization thereof, and are useful as chemical intermediates.

Abstract: Process for manufacturing a rhenium-containing catalyst comprising three steps of:dry impregnation of an alumina-containing porous carrier, at a temperature lower than 80.degree. C., for at least 10 hours,first thermal treatment at 85.degree.-250.degree. C., andsecond thermal treatment at 400.degree.-1000.degree. C.The obtained catalyst can be used for producing olefins by metathesis of other olefins.

Abstract: The invention concerns a process for manufacturing low density linear polyethylene by copolymerizing ethylene and 1-butene, comprising the steps of:(a) dimerizing ethylene to 1-butene in the presence of a soluble catalyst comprising: an alkyl titanate, an aluminum compound of formula AlR.sub.3 or AlR.sub.2 H, wherein R is a hydrocarbyl radical, and an ether;(b) contacting at least a portion of the product obtained in step (a) with an inorganic compound, at least partly insoluble;(c) contacting the insoluble mixture obtained in step (b) with an halogenated aluminum compound of formula Al.sub.2 R'.sub.6-n X.sub.n, wherein R' is a hydrocarbyl radical, X a halogen atom, and n a number from 3 to 6, when an halogenated aluminum compound is not already present in said mixture;(d) using the resultant product, containing at least one inorganic carrier, at least one halogenated aluminum compound and at least one titanium compound, as catalyst in the polymerization reactor.

Abstract: The invention concerns a process for reducing carbonylation of an aldehyde wherein the aldehyde is used as hemiacetalester, the reaction being conducted in the presence of a catalyst consisting of a cobalt carbonyl complex.The hemiacetal-ester may be formed in situ by reacting an acetal with an anhydride of acid.The process preferentially yields alkylene-glycol mono-esters, free of esterified, for a ratio H.sub.2 /CO ranging from 1:1 to 3:1 and preferentially 2-alkoxy aldehydes, for a ratio H.sub.2 /CO ranging from 0.1:1 to 0.5:1.

Abstract: Nickel, aluminum and chlorine derivatives which remain dissolved in olefin oligomers, after oligomerization in the presence of a nickel, aluminum, and chlorine-containing catalysts, are removed by successive treatments with:(a) anhydrous ammonia,(b) an aqueous solution of alkali metal hydroxide, a treatment with an aqueous solution containing at least one hydroxy-acid or at least one alkali metal salt of said hydroxyacid being performed after treatment (a) and before or after or simultaneously with treatment (b), and preferably a treatment with oxygen or with an oxygen-containing gas being performed before or after treatments (a) and (b) or simultaneously with these treatments. Preferably, tartaric acid or an alkali metal tartrate is used.

Abstract: Zeolite-metal catalysts having a substantial amount of catalytically active metal, e.g. iron, deposited in the cavities of the zeolite in zero-valent, small cluster form, are prepared by vaporizing the metal under low vapor pressure conditions in the vicinity of an organic liquid solvent, e.g. toluene, such that the metal dissolves in the solvent as a labile solvated zero-valent metal complex. This complex is contacted with the zeolite so that the complex diffuses into the cavities of the zeolite. Upon subsequent warming the solvated metal complex decomposes, leaving zero-valent small metal clusters in the zeolite cavities.