Propan metallation

Numerous patents have been issued disclosing catalysts and process schemes for manufacture of acrylonitrile from propane. These include the direct heterogeneously cataly2ed ammoxidation of propane to acrylonitrile using mixed metal oxide catalysts (61—64). 

A.ntioxidants. PhenoHc antioxidants, added at about 0.1—0.5 phr, are usually chosen from among butylated hydroxytoluene [128-37-0] (BHT), and Nnonylphenol [104-40-5] for Hquid stabilizer formulations and bisphenol A [80-05-7] (2,2-bis-(/)-hydroxyphenyl)propane) for the soHd systems. Low melting thioesters, dilauryl thiodipropionate [123-28-4] (DLTDP) or distearyl thiodipropionate [693-36-7] (DSTDP) are commonly added along with the phenoHcs to enhance their antioxidant performance. Usually a 3 1 ratio of thiodipropionate to phenoHc antioxidant provides the desired protection. Most mixed metal stabilizer products contain the antioxidant iagredient. 

Propane, 1-propanol, and heavy ends (the last are made by aldol condensation) are minor by-products of the hydroformylation step. A number of transition-metal carbonyls (qv), eg, Co, Fe, Ni, Rh, and Ir, have been used to cataly2e the oxo reaction, but cobalt and rhodium are the only economically practical choices. In the United States, Texas Eastman, Union Carbide, and Hoechst Celanese make 1-propanol by oxo technology (11). Texas Eastman, which had used conventional cobalt oxo technology with an HCo(CO)4 catalyst, switched to a phosphine-modified Rh catalyst ia 1989 (11) (see Oxo process). In Europe, 1-propanol is made by Hoechst AG and BASE AG (12). 

Carbonyl sulfide reacts with chlorine forming phosgene (qv) and sulfur dichloride [10545-99-0] and with ammonia forming urea and ammonium sulfide [12135-76-1]. Carbonyl sulfide attacks metals, eg, copper, ia the presence of moisture and is thought to be iavolved ia atmospheric sulfur corrosion (27,28). Its presence ia propane gas at levels above a few ppm may cause the gas to fail the copper-corrosion test. 

Joining two heteroatoms to a ring by radical combination is not presently a common route to heterocycles. It might become more important if the art of metal-catalyzed redox reactions keeps advancing at the present pace. Current examples are the conversion of 1,5-dithiols to 1,2-dithiepanes by oxidants such as FeCla, and the oxidation of 1,3-propane-bis-hydrazines to 1,2,3,4-tetrazepines (Sections 5.18.4.1 and 5.18.10.1). 

The inhibitive efficiency of alkali metal hydroxides increases with increased branching of polyethylene. This is confirmed by more pronounced effect of these hydroxides diminishing the yield of propane and propylene than in case of ethane and ethylene. The decreased yield of propane and propylene is also conditioned by more efficient inhibition of the macroradical isomerization stage by alkali metal hydroxides. Upon thermal destruction of polyethylene with the use of inhibitors the... 

Propane/Butane 235 psia Goodloe Metal approx. 0.80... 

The outlet valves of refillable butane cylinders are different from those of refillable propane cylinders. The valve for propane is a handwheel type, with a female 5/8 in BSP LEFT-HAND thread for a POL metal-to-metal connector. A compatible half-coupling must always be used to ensure a leak-free joint. 

As far as flame composition is concerned, it may be noted that an acetylene-air mixture is suitable for the determination of some 30 metals, but a propane-air flame is to be preferred for metals which are easily converted into an atomic vapour state. For metals such as aluminium and titanium which form refractory oxides, the higher temperature of the acetylene-nitrous oxide flame is essential, and the sensitivity is found to be enhanced if the flame is fuel-rich. 

Metal-halogen exchange of 10-bromo-5-ethyl-5//-dibenz[/>,/]azepinc (52) with butyllithium followed by quenching with acetone yields the propan-2-ol 53.214... 

Propane-1,2-diol, 3-mercapto-metal complexes, 2,804 Propan-l-ol, 2-amino-2-methyl-copper(II) complexes, 2,795 Propan-l-ol, 2,3-dimercapto-chelating agent heavy metal poisoning, 6,767 Propan-l-ol, 3-(methylamino)-copper(II) complexes, 2,795 Propan-2-ol... 

Bidentate sulphoxides, such as 1,3-bis(methylsulphinyl)propane, 1,4-bis(methyl-sulphinyl)butane and 1,2-bis(ethylsulphinyl)ethane, have been synthesized and employed as ligands toward Mn2 +, Co2 +, Ni2 +, Cu2 + and Zn2 + 204. All metal ions are bound to the ligands via the oxygen of the sulphoxide groups and are six-coordinate, as shown in Scheme 20, with the exception of Cu2+, which is four-coordinate. 

The simplest transition metal carbonyls are mononuclear of the type M(CO)x, in other words those with only one metal atom. They are hydrophobic but soluble to some extent in nonpolar liquids, such as n-butane or propane. The dinuclear carbonyls are more complex but have the same general characteristics as the mononuclear carbonyls. The carbonyls, which are or could be used in CVD, are listed in Table 3.4 with some of their properties. 

HfC is produced by CVD mostly on an experimental basis. The most common deposition system is the reaction of the metal chloride with a hydrocarbon, which can be propane (C3H8), propene (C3H6), toluene (C7Hg), or methane (CH4) as follows b H l... 

Additional adsorption sites are provided on open metal sites, when available. [Cu3(BTC)2] is performant in the selective adsorption and separation of olefinic compounds. The highly relevant separations of propene from propane and of isobutene from isobutane have been accomplished with separation factors of 2.0 and 2.1, respectively [101, 102]. [Cu3(BTC)2] also selectively takes up pentene isomers from aliphatic solvent in liquid phase, and even discriminates between a series of cis- and trans-olefin isomer mixtures with varying chain length, always preferring a double bond in cis-position. This behavior is ascribed to tt -complexation with the open Cu sites [100]. 

The application of ly transition metal carbides as effective substitutes for the more expensive noble metals in a variety of reactions has hem demonstrated in several studies [ 1 -2]. Conventional pr aration route via high temperature (>1200K) oxide carburization using methane is, however, poorly understood. This study deals with the synthesis of supported tungsten carbide nanoparticles via the relatively low-tempoatine propane carburization of the precursor metal sulphide, hi order to optimize the carbide catalyst propertira at the molecular level, we have undertaken a detailed examination of hotii solid-state carburization conditions and gas phase kinetics so as to understand the connectivity between plmse kinetic parametera and catalytically-important intrinsic attributes of the nanoparticle catalyst system. 

Nickel metal successfully catalyzes the hydrogenation of double bonds in unsaturated hydrocarbons such as propylene and butene. Can this metal also catalyze the dehydrogenation of alkanes such as propane and butane ... 

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