Abstract:
A nickel-carbene polymerization catalyst system for preparing high cis polydienes is provided. The catalyst system comprises (a) a nickel N-heterocyclic carbene complex, (b) an organoaluminum compound, (c) a fluorine-containing compound, and (d) optionally, an alcohol. Also provided is a process for producing a polydiene comprising reacting a conjugated diene in the presence of a polymerization catalyst comprising (a) a nickel N-heterocyclic carbene complex, (b) an organoaluminum compound, (c) a fluorine-containing compound, and (d) optionally, an alcohol.
Abstract:
A porous inorganic oxide support comprising an oxygen-containing carbonaceous material supported thereon, preferably a porous inorganic oxide support wherein the oxygen-containing carbonaceous material is a carbide of an oxygen-containing organic compound, wherein the ratio of the supported carbon amount with respect to the mass of the support for preparing the catalyst is from 0.05 to 0.2, the atomic ratio of the supported hydrogen amount with respect to the supported carbon amount is from 0.4 to 1.0, and the atomic ratio of the supported oxygen amount with respect to the supported carbon amount is from 0.1 to 0.6; and a hydrotreating catalyst of catalytic cracking gasoline which comprises the support and a catalyst containing a Group 8 metal of the periodic table, molybdenum (Mo), phosphorus and sulfur which is supported on the support are useful as a desulfurization catalyst of, for example, catalytic cracking gasoline at a hyperdesulfurized level, because of having functions of suppressing the hydrogenation activity of olefins and minimizing the decrease in the octane number even under reaction conditions with a high desulfurization ratio.
Abstract:
Supported metallic catalysts comprised of a Group VIII metal, a Group VIB metal, and an organic additive, and methods for synthesizing supported metallic catalysts are provided. The catalysts are prepared by a method wherein precursors of both metals are mixed and interacted with at least one organic additive, dried, calcined, and sulfided. The catalysts are used for hydroprocessing, particularly hydrodesulfurization and hydrodenitrogenation, of hydrocarbon feedstocks.
Abstract:
Use of ionic liquids as solvents in base-catalysed chemical reactions wherein the ionic liquid is composed of at least one species of cation and at least one species of anion, characterised in that a cation of the ionic liquid comprises a positively charge moiety and a basic moiety, and further wherein such ionic liquids may be used as promoters or catalysts for the chemical reactions.
Abstract:
Catalysts suitable for use in reforming hydrocarbons have a halogen promoter and a plurality of dispersed nanocatalyst particles supported on a solid support. The dispersed nanocatalyst particles are manufactured using a dispersing agent to control the size and/or crystal face exposure of the particles. The controlled size and dispersion of the nanocatalyst particles allows the reforming catalyst to be loaded with significantly less halogen promoter while still maintaining or increasing the catalyst's reforming performance. The catalysts of the present invention have shown improved C5+ production with the significantly reduced levels of halogen promoter.
Abstract:
A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; a selectivity control agent (SCA) comprising at least one silicon containing compound containing at least one C1-10 alkoxy group bonded to a silicon atom, and one or more activity limiting agent (ALA) compounds comprising one or more aliphatic or cycloaliphatic carboxylic acids; alkyl-, cycloalkyl- or alkyl(poly)(oxyalkyl)-(poly)ester derivatives thereof; or inertly substituted derivatives of the foregoing.
Abstract:
The present invention relates to the synthesis of chiral epoxides via a catalytic asymmetric oxidation of olefins. Additionally, the methodology provides a method of asymmetrically oxidizing sulfides and phosphines. This asymmetric oxidation employs a catalyst system composed of a metal and a chiral bishydroxamic acid ligand, which, in the presence of a stoichiometric oxidation reagent, serves to asymmetrically oxidize a variety of substrates.
Abstract:
The present invention relates to the synthesis of chiral epoxides via a catalytic asymmetric oxidation of olefins. Additionally, the methodology provides a method of asymmetrically oxidizing sulfides and phosphines. This asymmetric oxidation employs a catalyst system composed of a metal and a chiral bishydroxamic acid ligand, which, in the presence of a stoichiometric oxidation reagent, serves to asymmetrically oxidize a variety of substrates.
Abstract:
The present invention relates to catalyst systems of the Ziegler-Natta type, to a process for preparing them, to their use for the polymerization of olefins and to ethylene copolymers which can be prepared using this catalyst system.
Abstract:
The present invention relates to MgCl2.mROH.nH2O adducts, where R is a C1-C10 alkyl, 2≦m≦4.2, 0≦n≦0.7, characterized by an X-ray diffraction spectrum in which, in the range of 2&thgr; diffraction angles between 5° and 15°, the three main diffraction lines are present at diffraction angles 2&thgr; of 8.8±0.2°, 9.4±0.2° and 9.8±0.2°, the most intense diffraction lines being the one at 2&thgr;=8.8±0.2°, the intensity of the other two diffraction lines being at least 0.2 times the intensity of the most intense diffraction line. Catalyst components obtained from the adducts of the present invention are capable to give catalysts for the polymerization of olefins characterized by enhanced activity and stereospecificity with respect to the catalysts prepared from the adducts of the prior art.
Abstract translation:本发明涉及MgCl 2·mROH·nH 2 O加合物,其中R是C 1 -C 10烷基,2 <= m <= 4.2,0 <= n <0.7,其特征在于X射线衍射光谱,其中在 2θ衍射角在5°和15°之间的范围内,三条主要的衍射线分别以8.8±0.2°,9.4±0.2°和9.8±0.2°的衍射角2θ处存在,最强的衍射线为2θ= 8.8±0.2°,其他两条衍射线的强度是最强衍射线强度的0.2倍。由本发明的加合物得到的催化剂成分能够提供用于烯烃聚合的催化剂,其特征在于增强的 相对于由现有技术的加合物制备的催化剂的活性和立体定向性。