5042results about "Halogenated hydrocarbon preparation" patented technology

This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.

The invention discloses a new flow path to make C3-C13 hydrocarbonate at the beginning with methane, which is characterized by the following: transmitting methane into CH3Br and CH2Br2 acted by oxygen and HBr / H2O; reacting CH3Br and CH2Br2 in the second reactor to make C3-C13 hydrocarbonate and HBr; adopting HBr as circulated reacting dielectric in the making course of CH3Br and CH2Br2; making the transmitting rate of methane to 32.0% and the selectivity of CH3Br to 80-0% and the selectivity of CH2Br2 to 0.67%; entering the product in the first reactor and residual reacting material into the second reactor directly; making the transmitting rate of methane in the first reactor to 30.0% and total selectivity of CH3Br and CH2Br2 to 88% in the first reactor and the transmitting rate of CH3Br and CH2Br2 to 100% in the second reactor.

The present invention relates to compositions and processes of using perfluoropolyether to maintain or improve the oil return, lubrication, cooling capacity, or energy efficiency of a refrigeration, air conditioning or heat transfer system.

The invention discloses a catalyst which is used when methane is transformed into hydrobromic ether through the bromine oxidation reaction, and the catalyst which is used when preparing heavy hydrocarbons by using the hydrobromic ether further, and belongs to the technology field of the catalyst and the preparation method thereof. The first type of catalyst which is used when the methane is transformed into the hydrobromic ether through the bromine oxidation reaction comprises the preparation step that water-soluble metallic compound precursors such as Rh, Ru, Cu, Zn, Ag, Ce, V, W, Cd, Mo, Mn, Cr, La, etc. are mixed with a silica precursor, the mixture is processed through hydrolyzation, drying and roasting, and then the catalyst is obtained; the first type of catalyst can lead definite masses of reactant composed of the methane, HBr, H2O and oxygen sources (that is O2, air or oxygen-enriched air) to perform the catalytic bromine oxidation reaction, to generate target products such as CH3Br, CH2Br2, etc. The second type of catalyst, which is used when preparing the heavy hydrocarbons by using the hydrobromic ether further, includes the preparation step that molecular sieves such as HZSM-5, HY, H Beta, 3A, 4A, 5A, 13X, etc. load metallic compounds composed of Zn and Mg, so that the catalyst is obtained; the second type of catalyst can lead the methane bromination products composed of the CH3Br and the CH2Br2 to further react so as to generate the heavy hydrocarbons containing C3 to C13 and HBr, wherein, the HBr is used as a circular reaction medium.

A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

A continuous process is provided for the manufacture of haloalkanes by the reaction of carbon tetrachloride with olefins in the presence of iron metal, trialkylphosphate, and ferric chloride. A fraction of the catalyst and co-catalyst are separated after the reaction and recycled. In a preferred application, the olefin is ethene, and the haloalkane product is 1,1,1,3-tetrachloropropane. Two distillation steps take place in order to enhance the production of 1,1,1,3-tetrachloropropane.

One aspect of the present invention relates to ligands for transition metals. A second aspect of the present invention relates to the use of catalysts comprising these ligands in transition metal-catalyzed carbon-heteroatom and carbon-carbon bond-forming reactions. The subject methods provide improvements in many features of the transition metal-catalyzed reactions, including the range of suitable substrates, reaction conditions, and efficiency.

The present invention provides a process for regiospecific chlorination of an aromatic or aliphatic compound with a chlorine source comprising a metal chloride and other than Cl2 and SO2Cl2 in presence of hypervalent iodine catalyst and in acidic medium.

A mutant hydrolase optionally fused to a protein of interest is provided. The mutant hydrolase is capable of forming a bond with a substrate for the corresponding nonmutant (wild-type) hydrolase which is more stable than the bond formed between the wild-type hydrolase and the substrate and has at least two amino acid substitutions relative to the wild-type hydrolase. Substrates for hydrolases comprising one or more functional groups are also provided, as well as methods of using the mutant hydrolase and the substrates of the invention. Also provided is a fusion protein capable of forming a stable bond with a substrate and cells which express the fusion protein.

Photoacid generator salts comprising photoactive cationic moieties and segmented, highly fluorinated-hydrocarbon anionic moieties are disclosed which provide high photoacid strength and can be tailored for solubility and polarity. The present invention further relates to photoacid generators as they are used in photoinitiated acid-catalyzed processes for uses such as photoresists for microlithography and photopolymerization.

A process for converting gaseous alkanes to liquid hydrocarbons wherein a gaseous feed containing alkanes is reacted with a dry bromine vapor to form alkyl bromides and hydrobromic acid vapor. The mixture of alkyl bromides and hydrobromic acid are then reacted over a synthetic crystalline alumino-silicate catalyst, such as a ZSM-5 zeolite, at a temperature of from about 150° C. to about 400° C. so as to form higher molecular weight hydrocarbons and hydrobromic acid vapor. Hydrobromic acid vapor is removed from the higher molecular weight hydrocarbons. A portion of the propane and butane is removed from the higher molecular weight hydrocarbons and reacted with the mixture of alkyl bromides and hydrobromic acid over the synthetic crystalline alumino-silicate catalyst to form C5+ hydrocarbons.

A process for converting gaseous alkanes to liquid hydrocarbons wherein a gaseous feed containing alkanes is reacted with a dry bromine vapor to form alkyl bromides and hydrobromic acid vapor. The mixture of alkyl bromides and hydrobromic acid are then reacted over a synthetic crystalline alumino-silicate catalyst, such as a ZSM-5 zeolite, at a temperature of from about 150° C. to about 450° C. so as to form higher molecular weight hydrocarbons and hydrobromic acid vapor. Propane and butane which comprise a portion of the products may be recovered or recycled back through the process to form additional C5+ hydrocarbons. Various methods are disclosed to remove the hydrobromic acid vapor from the higher molecular weight hydrocarbons and to generate bromine from the hydrobromic acid for use in the process.

There are provided a liquid crystalline compound having a large negative Deltaepsilon, low viscosity, a large K33 / K11 value, a small Deltaepsilon / epsilonL and mutually excellent solubility even at extremely low temperature; a liquid crystal composition prepared from a liquid crystalline compound; and a liquid crystal display device fabricated from such a liquid crystal composition. The liquid crystalline compound of the present invention is a liquid crystalline compound represented by the following general formula (1): where, R<1 >represents hydrogen, fluorine, an alkyl group having 1 to 15 carbon atoms, or an alkenyl group having 2 to 15 carbon atoms; each of rings A<1>, A<2>, and A<3 >independently represents trans-1,4-cyclohexylene group, 1,4-cyclohexenylene group, trans-1,4-silacyclohexylene group, 1,4-phenylenegroup, 2,3-difluoro-1,4-phenylene group, 2-fluoro-1,4-phenylene group, 3-fluoro-1,4-phenylene group, pyrimidine-2,5-diyl group, pyridine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, tetrahydropyrane-2,5-diyl group, 1,3-dithiane-2,5-diyl group, or tetrahydrothiopyrane-2,5-diyl group; X<1 >represents hydrogen or fluorine; Y<1 >represents hydrogen or an alkyl group having 1 to 15 carbon atoms; 1 represents an integer from 1 to 10; and each of m and n independently represents 0 or 1.

The present invention relates to compositions comprising at least one fluoroolefin and an effective amount of stabilizer that may be an epoxide, fluorinated epoxide or oxetane, or a mixture thereof with other stabilizers. The stabilized compositions may be useful in cooling apparatus, such as refrigeration, air-conditioning, chillers, and heat pumps, as well as in applications as foam blowing agents, solvents, aerosol propellants, fire extinguishants, and sterilants.

The present invention relates to a method for preparation of organofluoro compounds containing radioactive isotope fluorine-18. More particularly, the present invention relates to a method for preparation of organofluoro compound [18F]florbetaben or [18F]AV-45 having <Chemistry Formula 11> and <Chemistry Formula 12>, respectively, by reacting fluorine salt containing radioactive isotope fluorine-18 with alkyl halide or alkyl sulfonate in the presence of alcohol of Chemistry Formula 1 as a solvent to obtain high yield of organofluoro compound. Synthesis reaction according to the present invention may be carried out under mild condition to give high yield of the organofluoro compounds and the reaction time is decreased, and thereby is suitable for the mass production of the organofluoro compounds.