Nickel formate-paraffin catalyst

Thermal decomposition of solids, resulting in liberation of a metal (see nickel formate-paraffin catalyst, p. 1631). 

Allison et al. prepared the catalyst by decomposing nickel formate in a paraffin-paraffin oil mixture in a vacuum of a water-stream pump.45 The nickel catalyst thus prepared was not pyrophoric, not sensitive to air and chloride, and showed excellent catalytic properties in the hydrogenation of aqueous solutions of aromatic nitro compounds such as the sodium salts of m-nitrobenzenesulfonic acid, o-nitrobenzoic acid, and p-nitrophenol at pH 5-6. Sasa prepared an active nickel catalyst for the hydrogenation of phenol by decomposing nickel formate in boiling biphenyl [boiling point (bp) 252°C], diphenyl ether (bp 255°C), or a mixture of them (see eq. 11.12)42... 

Ni Catalyst from Ni Formate (byAllisson et al.)45 In this method 100 g of nickel formate with 100 g of paraffin and 20 g of paraffin oil are heated in a vacuum of water-stream pump. At 170-180°C the water of crystallization is evolved out first (in 1 h). About 4 h at 245-255°C is required for complete decomposition. The end of the decomposition can best be found by the pressure drop to 20 mmHg. The still hot mass is poured on a plate after solidification, the upper paraffin layer is removed as much as possible. The remaining deep black mass is washed with hot water until most of the paraffin is removed off with melt the remaining powder is washed with alcohol, and then many times with petroleum ether until no paraffin remains. 

C with low conversion (10—15%) to limit dichloroalkane and trichloroalkane formation. Unreacted paraffin is recycled after distillation and the predominant monochloroalkane is dehydrochlorinated at 300°C over a catalyst such as nickel acetate [373-02-4]. The product is a linear, random, primarily internal olefin. 

Fischer-Tropsch Process. The Hterature on the hydrogenation of carbon monoxide dates back to 1902 when the synthesis of methane from synthesis gas over a nickel catalyst was reported (17). In 1923, F. Fischer and H. Tropsch reported the formation of a mixture of organic compounds they called synthol by reaction of synthesis gas over alkalized iron turnings at 10—15 MPa (99—150 atm) and 400—450°C (18). This mixture contained mostly oxygenated compounds, but also contained a small amount of alkanes and alkenes. Further study of the reaction at 0.7 MPa (6.9 atm) revealed that low pressure favored olefinic and paraffinic hydrocarbons and minimized oxygenates, but at this pressure the reaction rate was very low. Because of their pioneering work on catalytic hydrocarbon synthesis, this class of reactions became known as the Fischer-Tropsch (FT) synthesis. 

The solvent is 28 CC-olefins recycled from the fractionation section. Effluent from the reactors includes product a-olefins, unreacted ethylene, aluminum alkyls of the same carbon number distribution as the product olefins, and polymer. The effluent is flashed to remove ethylene, filtered to remove polyethylene, and treated to reduce the aluminum alkyls in the stream. In the original plant operation, these aluminum alkyls were not removed, resulting in the formation of paraffins (- 1.4%) when the reactor effluent was treated with caustic to kill the catalyst. In the new plant, however, it is likely that these aluminum alkyls are transalkylated with ethylene by adding a catalyst such as 60 ppm of a nickel compound, eg, nickel octanoate (6). The new plant contains a caustic wash section and the product olefins still contain some paraffins ( 0.5%). After treatment with caustic, cmde olefins are sent to a water wash to remove sodium and aluminum salts. 

The desired products are hydrocarbons in the C5 to C10 range that can be used in gasoline production. Iron-, cobalt- and nickel-based catalysts plus the proper selection of reaction temperatures and pressures are used to control product output. Increasing residence time in the reactor yields more paraffinic products and reduces the formation of alcohol and acid. 

Normal Paraffin-Based Olefins, Detergent range -paraffins are currently isolated from refinery streams by molecular sieve processes (see ADSORPTION, LIQUID separation) and converted to olefins by two methods. In the process developed by Universal Oil Products and practiced by Enichem and Mitsubishi Petrochemical, a -paraffin of the desired chain length is dehydrogenated using the Pacol process in a catalytic fixed-bed reactor in the presence of excess hydrogen at low pressure and moderately high temperature. The product after adsorptive separation is a linear, random, primarily internal olefin. Shell formedy produced olefins by chlorination—dehydrochlorination. Typically, C —C14 -paraffins are chlorinated in a fluidized bed at 300°C with low conversion (10—15%) to limit dichloroalkane and trichloroalkane formation. Unreacted paraffin is recycled after distillation and the predominant monochloroalkane is dehydrochlorinated at 300°C over a catalyst such as nickel acetate [373-02-4]. The product is a linear, random, primarily internal olefin. 

Iron, cobidt and nickel reinforce the formation of higher paraffinic hydrocarbons even a slight methanization proceeding along with the methanol synthesis was observed on some catalysts. 

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