Abstract: A process for producing a catalyst for olefin cracking, the process comprising the steps of providing an MFI-type crystalline silicate catalyst, heating the catalyst in steam to remove aluminum from the crystalline silicate framework and extracting aluminum from the catalyst by contacting the catalyst with a complexing agent for aluminum to remove from pores of the framework aluminum deposited therein during the steaming step thereby to increase the silicon/aluminum atomic ratio of the catalyst; and calcining the catalyst at elevated temperature.

Abstract: A process for the production of propylene from an olefinic feedstock containing at least one olefin of C4 or greater, the process comprising contacting the olefinic feedstock with a catalyst of the MFI-type having a silicon/aluminum atomic ratio of at least about 180 to produce an effluent containing propylene, the propylene yield on an olefin basis being from 30 to 50k based on the olefinic content of the feedstock.

Abstract: A process for the production of olefins by catalytic cracking, the process comprising feeding a hydrocarbon feedstock containing at least one olefin of C4 or greater over a MFI-type crystalline silicate catalyst to produce an effluent containing at least one olefin of C2 or greater by catalytic cracking which is selective towards light olefins in the effluent, whereby for increasing the catalyst stability by limiting formation of coke thereon during the cracking process the catalyst has a silicon/aluminum atomic ratio of at least about 180, the olefin partial pressure is from 0.1 to 2 bars, and the feedstock contacts the catalyst at an inlet temperature of from 500 to 600° C.

Abstract: A synthetic ester-containing lubricant with good soot-handling and, with friction modifier, viscosity modifier and antioxidant present, improved engine performance and cleanliness.

Abstract: A synthetic ester-containing lubricant with good soot-handling and, with friction modifier, viscosity modifier and antioxidant present, improved engine performance and cleanliness.

Abstract: A process for producing a catalyst for olefin cracking, the process comprising the steps of providing an MFI-type crystalline silicate catalyst, heating the catalyst in steam to remove aluminum from the crystalline silicate framework and extracting aluminum from the catalyst by contacting the catalyst with a complexing agent for aluminum to remove from pores of the framework aluminum deposited therein during the steaming step thereby to increase the silicon/aluminum atomic ratio of the catalyst; and calcining the catalyst at elevated temperature.

Abstract: Use of a catalyst system comprising a metallocene catalyst component of general formula R″ (CpRn)(Cp′R′n)MQ2 supported on an inert support in the slurry phase production of linear low density polyolefin, wherein Cp is a cyclopentadienyl moiety, Cp′ is a substituted or unsubstituted fluorenyl ring: R″ is a structural bridge imparting stereorigidity to the component; each R is independently hydrogen or hydrocarbyl having 1 to 20 carbon atoms in which 0≦m≦4; each R′ is independently hydrocarbyl having 1 to 20 carbon atoms in which 0≦n≦8; M is a Group IVB transition metal or vanadium; and each Q is hydrocarbyl having 1 to 20 carbon atoms or halogen; the metallocene having a centroid-M-centroid angle in the range 105° to 125°.

Abstract: A process for the catalytic cracking of at least one olefin in an olefinic stream containing impurities, the cracking process being selective towards light olefins in the effluent, the process comprising contacting a feedstock olefinic stream containing at least one sulphur-, nitrogen- and/or oxygen-derivative impurity with a crystalline silicate catalyst of the MFI-type, the catalyst having a silicon/aluminum atomic ratio of at least about 180, to produce an effluent stream having substantially the same olefinic content by weight as, but a different olefin distribution than, the feedstock stream.

Abstract: A process for the catalytic cracking of an olefin-containing feedstock which is selective towards light olefins in the effluent, the process comprising contacting a hydrocarbon feedstock containing at least one olefin with a MFI-type crystalline silicate catalyst having a silicon/aluminum atomic ratio of at least about 180, which has been obtained by pretreating so as to increase the silicon/aluminum atomic ratio thereof by heating the catalyst in steam and de-aluminating the catalyst by treating the catalyst with a complexing agent for aluminum, at an inlet temperature of from 500 to 600° C. and at an olefin partial pressure of from 0.1 to 2 bars to produce an effluent with an olefin content of lower molecular weight than that of the feedstock.

Abstract: A catalyst for olefin polymerization of the formula: R″(C4R′mC5C4R′n)XMeQ wherein X is an hetero atom ligand with one or two lone pair electrons selected from the elements of Group VA or VIA which is substituted or non-substituted: (C4Rm′C5C4Rn′) is a 3,6-substituted fluorenyl; R′ is hydrogen or hydrocarbyl radical having 1-20 carbon atoms, a halogen, an alkoxy, an alkoxy alkyl or an alkylamino or alkylsilyo radical, each R′ being the same or different and m and n independently are 1, 2, 3 or 4, with bilateral symmetry maintained; R″ is a structural bridge between S and (C4R′mC5C4R′n) to impart stereorigidity; Q is a hydrocarbyl radical having 1-20 carbon atoms or a halogen; Me is a Group IIIB, IVB, VB, or VIB metal having any of its theoretically possible oxidation states. Olefin monomers polymerised using these catalysts to form syndiotactic/atactic block polymers of high molecular weight and comprising at least 70% of syndiotactic triads.

Abstract: Use of a catalyst system comprising a metallocene catalyst component of general formula R″(CpRm) (Cp′R′n)MQ2 supported on an inert support in the slurry phase production of linear low density polyolefin, wherein Cp is a cyclopentadienyl moiety, Cp′ is a substituted or unsubstituted fluorenyl ring; R″ is a structural bridge imparting stereorigidity to the component; each R is independently hydrogen or hydrocarbyl having 1 to 20 carbon atoms in which 0≦m≦4; each R′ is independently hydrocarbyl having 1 to 20 carbon atoms in which 0≦n≦B; M is a Group IVB transition metal or vanadium; and each Q is hydrocarbyl having 1 to 20 carbon atoms or halogen; the metallocene having a centroid-M-centroid angle in the range 105° to 125°.

Abstract: A process for producing a Ziegler-Natta catalyst, the process comprising reacting an organo magnesium compound with a halogenated compound to produce crystalline magnesium halide having an intense diffraction line in an x-ray spectrum thereof at lattice distance within the range of from 2.56 to 3.20 Angstroms and titanating the magnesium halide by mixing the magnesium halide with a titanium compound whereby the titanated magnesium halide hasp in an x-ray spectrum thereof, a halo appearing at a lattice distance within the range from 2.56 to 3.30 Angstroms.

Abstract: A metallocene compound having the general formula: CpAXMQ1Q2Cp′A′X′M′Q1′Q2′ wherein Cp and Cp′ are each independently a substituted or unsubstituted cyclopentadienyl moiety; M and M′ are each independently a metal chosen from Group IV B transition metals and vanadium, and coordinate to Cp and Cp′ respectively; X and X′ are each independently a substituted or unsubstituted Group VA or VIA heteroatom and coordinate to M and M″ respectively; A and A′ are bridging groups between Cp and X and between Cp′ and X′ respectively and are independently chosen from —SiR′2—O—SiR′2—, —SinR′m—, —CnR′m— and —CR′2—SiR′2—CR′2—SiR′2—, in which each R′ is independently H or hydrocarbyl having 1 to 20 carbon atoms, n is an integer in the range 1 to 4 and m=2n; each Q1, Q2 and Q1′ and Q2′ is independe

Abstract: Provided is a high density multimodal polyethylene, having a shear ratio (SR) of 18 or more and comprising at least 20% by weight of a high molecular weight fraction, which high molecular weight fraction has: (a) a density (p) of 0.930 g/cm3 or less; and (b) a high load melt index (HLMI) of 0.30 g/10 mins or less.

Abstract: A metallocene compound having the general formula: CpAXMQ1Q2Cp′A′X′M′Q1′Q2′ wherein Cp and Cp′ are each independently a substituted or unsubstituted cyclopentadienyl moiety; M and M′ are each independently a metal chosen from Group IV B transition metals and vanadium, and coordinate to Cp and Cp′ respectively; X and X′ are each independently a substituted or unsubstituted Group VA or VIA heteroatom and coordinate to M and M′ respectively; A and A′ are bridging groups between Cp and X and between Cp′ and X′ respectively and are independently chosen from —SiR′2—O—SiR′2—, —SinR′m—, —CnR′m— and —CR′2—SiR′2—CR′2—SiR′2—, in which each R′ is independently H or hydrocarbyl having 1 to 20 carbon atoms, n is an integer in the range 1 to 4 and m=2n; each Q1, Q2 and Q1′ and Q2′ is independe

Abstract: Provided is a high density multimodal polyethylene, having a shear ratio (SR) of 18 or more and comprising at least 20% by weight of a high molecular weight fraction, which high molecular weight fraction has: (a) a density (p) of 0.930 g/cm3 or less; and (b) a high load melt index (HLMI) of 0.30 g/10 mins or less.

Abstract: A process for the preparation of polyethylene resins having a multimodal molecular weight distribution which comprises: (i) contacting ethylene monomer and a comonomer comprising an alpha-olefin having from 3 to 10 carbon atoms with a first catalyst system in a first reactor under first polymerization conditions to produce a first polyethylene having a first molecular weight, an HLMI of not more than 0.5 g/10 min and a first density of not more than 0.

Abstract: The present invention provides a process for preparing polyolefins having a multimodal or at least bimodal molecular weight distribution by contacting in a reaction mixture under polymeriation conditions at least one olefin and a catalyst system comprising a supported catalyst-component comprising an alumoxane and at least two metallocenes containing the same transition metal and selected from the group consisting of mono, di, and tri-cyclopentadienyls and substituted cyclopentadienyls of a transition metal and wherein at least one of the metallocenes is bridged and at least one of the metallocenes is unbridged.

Abstract: Bituminous compositions modified with self-adhesive cold-application polymers generally used for manufacturing of watertight roofing panels, said compositions comprising a mixture containing a rubbery styrene-diene polymeric mixture, one or more tackifying resins, and bitumen.

Abstract: A process for preparing polyolefins having a monomer length of up to C10, which comprises first contacting: (1) a metallocene catalyst component for the preparation of a polyolefin which comprises an isotactic polyolefin or syndiotactic/isotactic block polyolefin having a monomer length of up to C10, the component having the general formula: R″(CpR1R2R3)(Cp′R1′R2′)MQ2 wherein Cp is a cyclopentadienyl ring substituted with at least one substituent of R1R2 and/or R3; Cp′ is a substituted fluorenyl ring with substituents R1′ and R2′; R″ is a structural bridge imparting stereorigidity to the component; R1 is a substituent on the cyclopentadienyl ring which is distal to the bridge; R2 is a substituent on the cyclopentadienyl ring which is proximal to the bridge and positioned either non-vicinal or vicinal to the distal substituent; R3 is a substituent on the cyclopentadienyl ring which is proximal to the bridge; R1′ and R2′ are each independently substi