Abstract: The present invention concerns a process for the conversion of an olefinic C4 cut to polyisobutene and to propylene by metathesis. The process comprises three successive steps: (1) selective hydrogenation of diolefins with simultaneous isomerisation of 1-butene to 2-butenes, (2) polymerisation of the isobutene, including optional prior extraction of the isobutene, (3) metathesis of 2-butene with ethylene. Part or all of the C4 cut may originate from the metathesis of an olefinic C5 cut with ethylene after hydroisomerisation of the C5 cut. Application to C4 and C5 steam cracking cuts.

Abstract: The present invention concerns a plant for the conversion of an olefinic C.sub.4 or C.sub.5 cut to an alkyl-tertiobutylether or alkyl-tertioamylether and to propylene, by metathesis. The plant comprises four successive stages: (1) selective hydrogenation of the diolefins with simultaneous isomerisation of the alpha olefins to internal olefins; (2) etherification of the isoolefins; (3) elimination of oxygen-containing impurities; (4) metathesis of internal olefins with ethylene. Application to C.sub.4 and C.sub.5 steam cracking units.

Abstract: The invention concerns the catalytic alkylation of at least one isoparaffin selected from the group formed by isobutane and isopentane in the presence of at least one olefin containing 3 to 6 carbon atoms per molecule, using a catalyst comprising 40% to 99% by weight of an acid selected from acids with formula R--SO.sub.3 H where R is fluorine or an alkyl group or a fluorinated alkyl group, R preferably being F or CF.sub.3, and more preferably CF.sub.3, and 1% to 60% by weight of a solvent selected from the group formed by sulpholane, dimethylsulphoxide and dioxanes, preferably sulpholane.

Abstract: For the conversion of an olefinic C.sub.4 or C.sub.5 cut to an alkyl-tertiobutylether or alkyl-tertioamylether and to propylene, by metathesis, the process comprises four successive steps: (1) selective hydrogenation of the diolefins with simultaneous isomerisation of the alpha olefins to internal olefins; (2) etherification of the isoolefins; (3) elimination of oxygen-containing impurities; (4) metathesis of internal olefins with ethylene. The process has application, e.g., to C.sub.4 and C.sub.5 steam cracking cuts.

Abstract: The present invention concerns a process for the conversion of an olefinic C.sub.4 cut to polyisobutene and to propylene by metathesis. The process comprises three successive steps: (1) selective hydrogenation of diolefins with simultaneous isomerisation of 1-butene to 2-butenes, (2) polymerisation of the isobutene, including optional prior extraction of the isobutene, (3) metathesis of 2-butene with ethylene. Part or all of the C.sub.4 cut may originate from the metathesis of an olefinic C.sub.5 cut with ethylene after hydroisomerisation of the C.sub.5 cut. Application to C.sub.4 and C.sub.5 steam cracking cuts.

Abstract: The invention concerns the catalytic alkylation of at least one isoparaffin selected from the group formed by isobutane and isopentane in the presence of at least one olefin containing 3 to 6 carbon atoms per molecule, using a catalyst comprising 40% to 99% by weight of an acid selected from acids with formula R--SO.sub.3 H where R is fluorine or an alkyl group or a fluorinated alkyl group, R preferably being F or CF.sub.3, and more preferably CF.sub.3, and 1% to 60% by weight of a solvent selected from the group formed by sulpholane, dimethylsulphoxide and dioxanes, preferably sulpholane.

Abstract: The invention concerns a process for upgrading olefinic gasolines containing C.sub.5 hydrocarbons, but free of C.sub.4 hydrocarbons, by etherification. It is characterized in that the tertiary olefins of the charge are reacted (1 and 2) with methanol; the reaction effluent being then extracted (3) with water, in order to separate an aqueous phase containing the major part of the unreacted methanol from a hydrocarbon phase containing the major part of the formed ethers. The aqueous phase is then introduced in a distillation zone (4) where water is separated from methanol and recycled to the extraction zone (3), whereas methanol is recycled to the etherification zone (1 and 2).

Abstract: Process for producing a hydrocarbon cut of high octane number by etherification of an olefin-containing hydrocarbon cut.The olefinic cut, to which methanol is added, passes into an etherification reactor (1) wherefrom are separated (3) a bottom product (15) containing ethers, and a top product (14) containing residual methanol and unreacted light olefins. This top product passes into an etherification reactor (2) and then is washed with water (8).The top product is finally admixed with the bottom product.The so-obtained motor-fuel has a higher octane number than that of the initial hydrocarbon cut.

Abstract: Process for producing very pure olefins of the formula ##STR1## by decomposition of the corresponding ethers of formula ##STR2## wherein R.sub.1 and R.sub.3 are selected from the group of the alkyl, arylalkyl aryl or alkylaryl radicals, R and R.sub.2 being a hydrogen atom or a radical selected from said above mentioned group, in the presence of steam in a molar proportion from 2 to 8 times the ether amount and with the use of a catalyst comprising alumina to which is added 0.01 to 5% by weight of titanium or zirconium or hafnium as metal or as metal compound, said catalyst having a specific surface from 80 to 300 m.sup.2 /g.

Abstract: Process for producing ethers by reacting a catalytic cracking C.sub.4 olefinic cut which may contain such impurities as NaOH, an alkanolamine, an alkaline earth metal compound or an iron, copper or lead compound, with an alcohol, in the liquid phase, in the presence of an expanded bed of an etherification solid catalyst of the sulfonic resin type in acid form, in a circuit of two or more successive reaction zones wherethrough the order of passage of the reactants is periodically modified by disconnecting the first zone from the circuit, feeding the reactants to the second zone, replacing the catalyst of the first zone with fresh catalyst and thereafter connecting said first zone at the end of the circuit.

Abstract: An unsaturated C.sub.5 fraction comprising at least 10% of a mixture (A) of 2-methyl-1-butene with 2-methyl-2-butene and optionally isoprene and at least 10% of a mixture (B) of other mono-olefins and diolefins is hydrogenated under controlled conditions and thereafter etherified with an alcohol having from 1 to 4 carbon atoms. A gasoline fraction of high motor octane number and low olefin content is thus obtained.

Abstract: Process for producing methyl tert-butyl ether (MTBE) by reacting methanol with the isobutene present in a C.sub.4 cut in a proportion from 10 to 60%, wherein said cut, admixed with methanol is contacted, in a first reaction zone, with an acid catalyst in the conditions of etherification of isobutene by methanol unit 93 to 98% of the isobutene has been converted, the reaction product is fractionated under at least 10 bars to a bottom fraction consisting essentially of MTBE and a top fraction which is contacted, in a second reaction zone, with an acid catalyst, under the conditions of etherification of isobutene by methanol, until at least 99% of the initial isobutene has been converted, the resulting product is washed with water and separated into a residual C.sub.4 cut which is discharged and an aqueous phase wherefrom methanol is recovered by distillation.

Abstract: Methyl tert.butyl ether is obtained by reacting an isobutene-containing C.sub.4 cut with methanol and distilling the reaction product at a superatmospheric pressure of 7-30 atm. abs. to recover a top fraction and a bottom fraction containing methyl tert.butyl ether. The isobutene conversion rate and the purity of the ether are increased by recycling a portion of the top fraction to the reaction zone.

Abstract: Process for producing gasoline of high octane number from C.sub.3 and C.sub.4 olefinic cuts, such as those obtained by fractional distillation of a C.sub.3 / C.sub.4 catalytic cracking cut, comprising the steps of:(a) oligomerizing propylene of the C.sub.3 cut to obtain a first gasoline fraction,(b) reacting the isobutene of the C.sub.4 cut with methanol to produce methyl tert.-butyl ether which is separated from the unreacted C.sub.4 hydrocarbons to form a second gasoline fraction,(c) alkylating said unreacted C.sub.4 hydrocarbons with isobutane in the presence of an alkylation catalyst such as hydrofluoric acid, to form a third gasoline fraction, and(d) admixing, at least partially, said first, second and third gasoline fractions, so as to obtain gasoline of high octane number.

Abstract: High octane gasoline is obtained from C.sub.3 /C.sub.4 olefinic cuts by a combination of steps: oligomerization of the C.sub.3 fraction, hydroisomerization of 1-butene in the C.sub.4 cut, fractionation of the resultant C.sub.4 cut, hydrogenation of isobutene and alkylation. Resultant fractions are admixed to produce the desired high octane gasoline.

Abstract: Lead free gasoline of high octane number is obtained from C.sub.3 and C.sub.4 olefinic cuts as follows: propylene contained in the C.sub.3 cut is oligomerized, at least 80% of the isobutene and less than 40% of the n-butenes of the C.sub.4 cut are oligomerized to form an oligomerizate distilling in the gasoline range, which is separated from the unreacted C.sub.4 hydrocarbons, the latter are subsequently alkylated to form a gasoline fraction which can be admixed with the oligomerizates of the C.sub.3 and the C.sub.4 cuts to produce the desired high octane gasoline.

Abstract: An ether is prepared by reacting a selected olefin with an alcohol in a two reaction zone system: in the first reaction zone, the catalyst is dispersed in the liquid phase of the reactants and boiling of the mixture is avoided; in the second reaction zone, the catalyst is in a fixed bed. A cooled recycle stream is fed back to the first stage reactor. The catalyst is a sulfonated ion exchange resin in the acid form.

Abstract: For polymerizing unsaturated hydrocarbons into oligomers with acid catalysts, there are employed liquid catalyst compositions containing a Bronsted acid and a sulfone of formula R--SO.sub.2 --R', wherein R and R' are each separately a monovalent radical containing from 1 to 8 carbon atoms or form together a divalent radical having from 3 to 12 carbon atoms, the acid concentration being at least 10.sup.-.sup.5 moles per liter of sulfone and at most the saturation concentration without exceeding 5 moles per liter of sulfone. The catalysts may be dispersed in an inert hydrocarbon solvent and Lewis acids may also be added.