Liquid fuel oxidation reaction

HALF-CELL DESIGN TO MIMIC FUEL CELL ELECTRODE SITUATION FOR LIQUID FUEL OXIDATION REACTION [24]... 

Any compound or mixture of compounds capable of undergoing an exothermic reaction is a potential monopropellant. In this sense all solid propellants are monopropellants. The term monopropellant however generally is reserved for liquid propellants. The monopropellant may be a single compound such as hydrogen peroxide or propyl nitrate. For hydrogen peroxide, the exothermic reaction is in the form of a decomposition. The exothermic reaction associated with propyl nitrate is better characterized as a fuel-oxidizer reaction, the fuel and oxidizer in... 

Liquid methanol has been investigated as the anode fuel in PEM fuel cells, due to ease of handling methanol, its low cost, and widespread availability. The fuel oxidation reaction here is... 

The anodic oxidation of methanol was considered as one of the most interesting subjects in electrochemistry during the last 15 years. Besides very characteristic reaction pathways and electrocatalytic effects, the methanol molecule with its four hydrogen atoms is the basis of a high-energy density liquid fuel. The reaction of methanol with oxygen follows the chemical route... 

Ammonia is the precursor for many other chemicals such as nitric acid, hydrazine, acrylonitrile, and hexamethylenediamine. Ammonia, having three hydrogen atoms per molecule, may be viewed as an energy source. It has been proposed that anhydrous liquid ammonia may be used as a clean fuel for the automotive industry. Compared with hydrogen, anhydrous ammonia is more manageable. It is stored in iron or steel containers and could be transported commercially via pipeline, railroad tanker cars, and highway tanker trucks. The oxidation reaction could be represented as ... 

Direct conversion of methane to ethane and ethylene (C2 hydrocarbons) has a large implication towards the utilization of natural gas in the gas-based petrochemical and liquid fuels industries [ 1 ]. CO2 OCM process provides an alternative route to produce useful chemicals and materials where the process utilizes CO2 as the feedstock in an environmentally-benefiting chemical process. Carbon dioxide rather than oxygen seems to be an alternative oxidant as methyl radicals are induced in the presence of oxygen. Basicity, reducibility, and ability of catalyst to form oxygen vacancies are some of the physico-chemical criteria that are essential in designing a suitable catalyst for the CO2 OCM process [2]. The synergism between catalyst reducibility and basicity was reported to play an important role in the activation of the carbon dioxide and methane reaction [2]. 

Metals and metal oxides, as a rule, accelerate the liquid-phase oxidation of hydrocarbons. This acceleration is produced by the initiation of free radicals via catalytic decomposition of hydroperoxides or catalysis of the reaction of RH with dioxygen (see Chapter 10). In addition to the catalytic action, a solid powder of different compounds gives evidence of the inhibiting action [1-3]. Here are a few examples. The following metals in the form of a powder retard the autoxidation of a hydrocarbon mixture (fuel T-6, at T= 398 K) Mg, Mo, Ni, Nb V, W, and Zn [4,5]. The retarding action of the following compounds was described in the literature. 

Fischer-Tropsch A process for converting synthesis gas (a mixture of carbon monoxide and hydrogen) to liquid fuels. Modified versions were known as the Synol and Synthol processes. The process is operated under pressure at 200 to 350°C, over a catalyst. Several different catalyst systems have been used at different periods, notably iron-zinc oxide, nickel-thoria on kieselgtihr, cobalt-thoria on kieselgiihr, and cemented iron oxide. The main products are C5-Cn aliphatic hydrocarbons the aromatics content can be varied by varying the process conditions. The basic reaction was discovered in 1923 by F. Fischer and... 

A POX reformer also can be used for converting gaseous fuels, but does not produce as much hydrogen as the steam reformers. For example, a methane-fed POX reformer would produce only about 75% of the hydrogen (after shifting) that was produced by an SR. Therefore, partial oxidation reformers are typically used only on liquid fuels that are not well suited for steam reformers. Partial oxidation reformers rank second after steam reformers with respect to their hydrogen yield. For illustration, the overall POX reaction (exothermic) for methane is... 

Liquid fuels such as distillate, naphtha, diesel oils, and heavy fuel oil can be reformed in partial oxidation reformers. All commercial POX reactors employ noncatalytic POX of the feed stream by oxygen in the presence of steam with reaction temperatures of approximately 1,300 to 1,500°C (2,370 to 2,730°F) (18). For illustration, the overall POX reaction for pentane is... 

The PtRu bimetallic system has been the catalyst of choice for MeOH oxidation in acid elecfrolyfes since its discovery by workers at Shell in the early 1960s2 In practice, PtRu lowers the overpotential for MeOH oxidation by >200 mV compared to pure Pt. The MeOH oxidation reaction on Pt and PtRu is probably the most studied reaction in fuel cell electrocatalysis due to its ease of sfudy in liquid electrolytes and the many possible mechanistic pathways. In recent years, the deposition of PtRu particles onto novel carbon supports and the novel PtRu particle preparation routes have proved popular as a means to demonstrate superiority over conventional PtRu catalysts. 

Rocket Engine. A non-airbreathing reaction propulsion device that consists essentially of an injector, thrust chambers) and exhaust nozzle(s), and utilizes liquid fuels and oxidizers at controlled rates from which hot gases are generated by combustion and expanded thru a nozzle(s) (Ref 40a, p 125)... 

This section addresses the role of chemical surface bonding in the electrochemical oxidation of carbon monoxide, CO, formic acid, and methanol as examples of the electrocatalytic oxidation of small organics into C02 and water. The (electro)oxidation of these small Cl organic molecules, in particular CO, is one of the most thoroughly researched reactions to date. Especially formic acid and methanol [130,131] have attracted much interest due to their usefulness as fuels in Polymer Electrolyte Membrane direct liquid fuel cells [132] where liquid carbonaceous fuels are fed directly to the anode catalyst and are electrocatalytically oxidized in the anodic half-cell reaction to C02 and water according to... 

This title is somewhat misleading. The following article is primarily concerned with expl reactions of fuel mists (and/or vapors) with oxygen of the air. The article does not include consideration of flash vaporizations that occur when very hot substances (molten A1 for example) come into contact with a volatile liquid (eg, water), nor does it concern itself with steam-boiler type explns. Thus the subject matter of this article deals with rapid fuel oxidations with the oxidant usually provided by the oxygen of the air, though reactions of monopropellant type mists will also be considered. Most of the fuels of interest are liquids at ordinary ambient conditions... 

In the petrochemical industry it is of interest to develop processes that convert a gaseous fuel, such as methane, to a liquid fuel, such as methanol or formaldehyde, by partial oxidation. It has proved difficult, however, to identify reaction conditions with a sufficient yield of CH2O from CH4. The problem is that the rate of CH2O oxidation is large compared to the rate of methane oxidation, and for this reason it is difficult to avoid subsequent conversion of CH2O to CO in the oxidative process. 

Acohols - [ALCOHOL FUELS] (Vol 1) - [FEEDSTOCKS-COALCHEMICALS] (Vol 10) - [DISTILLATION, AZEOTROPIC AND EXTRACTIVE] (Vol 8) - [COALCONVERSIONPROCESSES - LIQUEFACTION] (Vol 6) - [FLAME RETARD ANTS - PHOSPHORUS FLAME RETARD ANTS] (Vol 10) - [EXPLOSIVES AND PROPELLANTS - PROPELLANTS] (Vol 10) -as antifreeze [ANTIFREEZES AND DEICING FLUIDES] (Vol 3) -for automotive motor fuel [FUELS, SYNTHETIC - LIQUID FUELS] (Vol 12) -from castor oil [CASTOR OIL] (Vol 5) -in ceramic processing [CERAMICS - CERAMIC PROCESSING] (Vol 5) -from hydrocarbon oxidation [HYDROCARBON OXIDATION] (Vol 13) -as hypnotic and sedative [HYPNOTICS, SEDATIVES, ANTICONVULSANTS, AND ANXIOLYTICS] (Vol 13) -m metal polishes [POLISHES] (Vol 19) -from oxo process [OXO PROCESS] (Vol 17) -permanganate oxidation [MANGANESE COMPOUNDS] (Vol 15) -reactions with silanes [SILICON COMPOUNDS - SILANES] (Vol 22) -role m mineral processing [MINERALS RECOVERY AND PROCESSING] (Vol 16)... 

The precious-metal platinum catalysts were primarily developed in the 1960s for operation at temperatures between about 200 and 300°C (1,38,44). However, because of sensitivity to poisons, these catalysts are unsuitable for many combustion applications. Variations in sulfur levels of as little as 0.4 ppm can shift the catalyst required temperature window completely out of a system s operating temperature range (44). Additionally, operation with liquid fuels is further complicated by the potential for deposition of ammonium sulfate salts within the pores of the catalyst (44). These low temperature catalysts exhibit NO conversion that rises with increasing temperature, then rapidly drops off, as oxidation of ammonia to nitrogen oxides begins to dominate the reaction (see Fig. 7). 

The bomb calorimeter provides the most suitable and accurate apparatus for determination of the calorific values of solid and liquid fuels. Since the combustion takes place in a closed system, heat transfer from the calorimeter to the water is complete, and since the reaction is one between the fuel and gaseous oxygen, no corrections are necessary for the heat absorbed during the reduction of the oxidizing agent. In addition, the losses due to radiation can be reduced to comparatively small quantities, and more important, can be determined with a considerable degree of accuracy. Corrections due to the heat evolved in the formation of nitric and sulfuric acids under the conditions existing in the bomb can be determined accurately. 

Let us consider the symmetrical burning of a spherical droplet with the radius rp in surroundings without convection. Assume that there is an infinitely thin flame zone from the surface of the droplet to the radial distance rn [137], which is much larger than the radius of the droplet, rp. The heat released from the burning is conducted back to the surface to evaporate liquid fuel for combustion. Because the reaction is extremely fast, there exists no oxidant in the range of rp< r < m while no fuel vapor is available at r > rn. At a quasi steady state the mass flux through the spherical surface with the radius r (>rp), Mfv, can be obtained with Fick s law as... 

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