8608results about "Catalytic reactions" patented technology

The present invention relates to an olefin metathesis reaction catalyst where rhenium (Re) oxide or molybdenum (Mo) oxide is supported, as a catalyst main component, on a surface-modified mesoporous silica or mesoporous alumina support, and a preparation method therefor. The olefin metathesis reaction catalyst of the present invention allows highly efficient metathesis of long-chain unsaturated hydrocarbons having at least eight carbons at a low temperature of 150° C. or lower. The catalyst can be separated readily from reaction solution, regenerated at a low temperature of 400° C. or lower by removing toxins accumulated on it during the metathesis reaction, and used repeatedly in metathesis reaction many times, thereby being made good use in commercial olefin metathesis processes.

A catalyst composition and process for the conversion of linear and / or branched paraffin hydrocarbons based on the use of an ionic liquid catalyst in combination with a Brønsted Acid, which provides a catalytic composition with an increased activity compared with said ionic liquid. Under suitable reaction conditions this conversion is leading to paraffin hydrocarbon fraction with higher octane number.

A method and a system for producing a change in a medium disposed in an artificial container. The method places in a vicinity of the medium at least one of a plasmonics agent and an energy modulation agent. The method applies an initiation energy through the artificial container to the medium. The initiation energy interacts with the plasmonics agent or the energy modulation agent to directly or indirectly produce the change in the medium. The system includes an initiation energy source configured to apply an initiation energy to the medium to activate the plasmonics agent or the energy modulation agent.

The invention provides a method for converting a less active or slower to initiate system to a higher activity system so that at the end of a polymerization the most active species is present in the system. The invention generally relates to a process for converting a less active or slower to initiate catalyst system to a higher activity catalyst system wherein the process comprises contacting a protected N-heterocyclic carbene with a metathesis catalyst and an olefin in the presence of energy. One of the benefits of the invention is that the amount of catalyst required is less than or lowered in the presence of the protected N-heterocyclic carbene as compared to the amount of catalyst required in the absence of the protected N-heterocyclic carbene. The protected N-heterocyclic carbene can be unsaturated or saturated. In addition, the invention describes novel ruthenium initiators and methods of making the same.

The present invention relates to catalyst composition for oligomerizing ethylene and its application. The catalyst composition includes complex of acetylacetone chromium, tetrahydrofuran chromium chloride and / or chromium isooctanate; ligand containing P and N; activator of methyl aluminoxane, ethyl aluminoxane, propyl aluminoxane and / or butyl aluminoxane; and promoter of X1R6X2, where, each of X1 and X2 is F, Cl, Br, I or alkoxyl, and R6 is alkyl or aryl group; with the molar ratio of the complex, the ligand, the activator and the promoter being 1 to 0.5-10 to 50-3000 to 0.5-10. The catalyst composition is used in oligomerizing reaction of ethylene to prepare 1-octene, and has high catalytic activity and high 1-octene selectivity.

The invention describes a process for tetramerisation of olefins wherein the product stream of the process contains more than 30% of the tetramer olefin. The process includes the step of contacting an olefinic feedstream with a catalyst system containing a transition metal compound and a heteroatomic ligand.

This disclosure provides for alpha olefin oligomers and polyalphaolefins (or PAOs) and methods of making the alpha olefin oligomers and PAOs. This disclosure encompasses metallocene-based alpha olefin oligomerization catalyst systems, including those that include at least one metallocene and an activator comprising a solid oxide chemically-treated with an electron withdrawing anion. The alpha olefin oligomers and PAOs prepared with these catalyst systems can have a high viscosity index combined with a low pour point, making them particularly useful in lubricant compositions and as viscosity modifiers.

Chelating ligand precursors for the preparation of olefin metathesis catalysts are disclosed. The resulting catalysts are air stable monomeric species capable of promoting various metathesis reactions efficiently, which can be recovered from the reaction mixture and reused. Internal olefin compounds, specifically beta-substituted styrenes, are used as ligand precursors. Compared to terminal olefin compounds such as unsubstituted styrenes, the beta-substituted styrenes are easier and less costly to prepare, and more stable since they are less prone to spontaneous polymerization. Methods of preparing chelating-carbene metathesis catalysts without the use of CuCl are disclosed. This eliminates the need for CuCl by replacing it with organic acids, mineral acids, mild oxidants or even water, resulting in high yields of Hoveyda-type metathesis catalysts. The invention provides an efficient method for preparing chelating-carbene metathesis catalysts by reacting a suitable ruthenium complex in high concentrations of the ligand precursors followed by crystallization from an organic solvent.

A process for preparing a hydrocyanation catalyst comprising contacting a bidentate phosphorous-containing ligand with a molar excess of nickel chloride in the presence of a nitrile solvent and a reducing metal which is more electropositive than nickel. Preferably, the nickel chloride is dried before use.

The invention relates to novel carbene ligands and their incorporated monomeric and resin / polymer linked ruthenium catalysts, which are recyclable and highly active for olefin metathesis reactions. It is disclosed that significant electronic effect of different substituted 2-alkoxybenzylidene ligands on the catalytic activity and stability of corresponding carbene ruthenium complexes, some of novel ruthenium complexes in the invention can be broadly used as catalysts highly efficient for olefin metathesis reactions, particularly in ring-closing (RCM), ring-opening (ROM), ring-opening metathesis polymerization (ROMP) and cross metathesis (CM) in high yield. The invention also relates to preparation of new ruthenium complexes and the use in metathesis.

One aspect of the present invention relates to ionic liquids comprising a pendant Bronsted-acidic group, e.g., a sulfonic acid group. Another aspect of the present invention relates to the use of an ionic liquid comprising a pendant Bronsted-acidic group to catalyze a Bronsted-acid-catalyzed chemical reaction. A third aspect of the present invention relates to ionic liquids comprising a pendant nucleophilic group, e.g., an amine. Still another aspect of the present invention relates to the use of an ionic liquid comprising a pendant nucleophilic group to catalyze a nucleophile-assisted chemical reaction. A fifth aspect of the present invention relates to the use of an ionic liquid comprising a pendant nucleophilic group to remove a gaseous impurity, e.g., carbon dioxide, from a gas, e.g., sour natural gas.

A catalyst system comprising:(a) one or more bisarylimino pyridine iron or cobalt catalysts;(b) a first co-catalyst compound which is selected from aluminium alkyls, aluminoxanes, and mixtures thereof; and(c) a second co-catalyst compound which comprises one or more compounds of the formula ZnR′2 wherein each R′, which may be the same or different, is selected from hydrogen, optionally substituted C1–C20 hydrocarbyl, phenyl, Cl, Br, I, SR″, NR″2, OH, OR″, CN, NC wherein R″, which within the same molecule may the same or different, is C1–C20 hydrocarbyl.

The invention provides a process for polymerising olefins to branched polyolefins in the presence of a polymerisation catalyst and a cocatalyst, wherein the cocatalyst produces 1-octene in a selectivity greater than 30%.

The invention describes a process for tetramerisation of olefins wherein the product stream of the process contains more than 30% of the tetramer olefin. The process includes the step of contacting an olefinic feedstream with a catalyst system containing a transition metal compound and a heteroatomic ligand.

Novel iron and cobalt complexes of certain novel tricyclic ligands containing a “pyridine” ring and substituted with two imino groups are polymerization and / or oligomerization catalysts for olefins, especially ethylene. Depending on the exact structure of the ligand, and polymerization process conditions, products ranging from α-olefins to high polymers may be produced. The polymers, especially polyethylenes, are useful for films and as molding resins.

A process for regenerating a used acidic catalyst which has been deactivated by conjunct polymers by removing the conjunct polymers so as to increase the activity of the catalyst is disclosed. Methods for removing the conjunct polymers include hydrogenation, addition of a basic reagent and alkylation. The methods are applicable to all acidic catalysts and are described with reference to certain ionic liquid catalysts.

This invention relates generally to olefin metathesis, and more particularly relates to the synthesis of terminal alkenes from internal alkenes using a cross-metathesis reaction catalyzed by a selected olefin metathesis catalyst. In one embodiment of the invention, for example, a method is provided for synthesizing a terminal olefin, the method comprising contacting an olefinic substrate comprised of at least one internal olefin with ethylene, in the presence of a metathesis catalyst, wherein the catalyst is present in an amount that is less than about 1000 ppm relative to the olefinic substrate, and wherein the metathesis catalyst has the structure of formula (II) wherein the various substituents are as defined herein. The invention has utility, for example, in the fields of catalysis, organic synthesis, and industrial chemistry.

The present invention provides compositions comprising metal complexes, and related methods. In some embodiments, metal complexes of the invention may be useful as catalysts for chemical reactions, including metathesis reactions, wherein the catalysts exhibit enhanced activity and stereoselectivity. In some embodiments, the invention may advantageously provide metal complexes comprising a stereogenic metal atom. Such metal complexes may be useful in enantioselective catalysis.

Catalysts comprised of at least one catalytically active element and at least one helper catalyst are disclosed. The catalysts may be used to increase the rate, the selectivity or lower the overpotential of chemical reactions. These catalysts may be useful for a variety of chemical reactions including in particular the electrochemical conversion of carbon dioxide to formic acid.

The invention provides an adduct comprising a carbon nanotube and a transitional metal coordination complex, wherein the metal of the complex is attached by a covalent linkage to at least one oxygen moiety on the nanotube.

Provided herein are catalysts useful in providing foam products which are produced using an organic poly isocyanate as a starting material. A catalyst according to the present invention includes the tris-(hydroxyethyl)methyl ammonium cation, and optionally potassium cation, in combination with a variety of possible counter anions present to maintain charge balance and for compatibility. A catalyst according to the invention is preferably used in conjunction with one or more conventional tertiary amine catalysts in a foam producing process. The foams may be polyurethane foams, polyisocyanurate foams, flexible foams, or elastomeric foams.

A chelated hydroprocessing catalyst exhibiting low moisture is obtained by hearing an impregnated, calcined carrier to a temperature higher than 200° C. and less than a temperature and for a period of time that would cause substantial decomposition of the chelating agent.

Novel catalyst systems for metathesis reactions, in particular for the metathesis of nitrile rubber, which contain a specific salt additive in addition to the metathesis catalyst are provided.