Hydrocarbon liquid, fuels

As well known, the liquid hydrocarbon fuels contain not only sulfur compounds but also a large number of aromatic compounds that have aromatic skeleton structure similar to the coexisting sulfur compounds. This inherent problem makes a great challenge in development of an effective adsorbent with high adsorptive selectivity for the sulfur compounds. Consequently, many ODS methods for liquid hydrocarbon fuels have been explored. Early work in ODS of thiophenic compounds in the pres- 

The second step is the removal of the produced sulfoxides and/or sulfones by adsorption, abstraction, and/or abstraction. The advantages of the ODS are that it avoids the use of hydrogen and allows the process to be conducted at ambient conditions, which is much more efficient energetically. More interesting is that the oxidation reactivity of 4,6-DMDBT in the presence of a mixture of hydrogen peroxide and formic acid is higher than that of DBT, as reported by Otsuki et al.234 

Recently, Ma et al.238 explored a novel ODS method of liquid hydrocarbon fuels, which combines a catalytic oxidation step of the sulfur compounds using molecular oxygen followed by an adsorption step to remove oxidized sulfur compounds in the treated fuel using an AC. The ODS of an MJF and a real JP-8 jet fuel was conducted in a batch system at ambient conditions. They found that the oxidation using 

The ultradeep desulfurization of the current commercial fuels has become a bottleneck in hydrogen production for fuel cell applications. It is urgent to develop a more efficient and environmentally friendly process and technology for the ultradeep desulfurization of the hydrocarbon fuels for fuel cell applications. Many approaches have been conducted in the improvement of the conventional HDS process or development of new alterable processes. These approaches include (a) catalytic HDS with improved and new catalysts, reactor, and/ or process (b) selectively adsorptive desulfurization and (c) ODS and others. 

Current progress in HDS via improvement of conventional catalysts, reactors, and processes or development of new catalysts, reactors, and processes has allowed the refining industry to be able to produce the low-sulfur fuels to meet the new EPA regulation. However, the current HDS technology is still difficult or costly to produce the ultraclean liquid hydrocarbon fuels for fuel cell applications. Adsorptive desulfurization and ODS are two promising alterable technologies for ultradeep desulfurization of hydrocarbons fuels for fuel cell applications. 

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Our complex modern life style was made possible by the discovery and refining of fossil fuels, fuels that are the result of the decay of organic matter laid down millions of years ago. The natural gas that heats our homes, the gasoline that powers our automobiles, and the coal that provides much of our electrical power are fossil fuels. Vast reserves of petroleum, the source of liquid hydrocarbon fuels such as gasoline and coal, exist in many areas of the world. However, although large, these reserves are limited, and we are using them up at a much faster rate than they can be replaced. 

A hydrogen fuel cell is environmentally friendly, but H2 is much more difficult to store than liquid fuels. The production, distribution, and storage of hydrogen present major difficulties, so researchers are working on fuel cells that use liquid hydrocarbon fuels. One such fuel cell is composed of layers of yttria-stabilized zirconia (YSZ), which is solid Zr02 containing around 5% Y2 O3. This cell uses the combustion of a... 

The DMFC is the most attractive type of fuel cell as a powerplant for electric vehicles and as a portable power source, because methanol is a liquid fuel with values for the specific energy and energy density being about equal to half those for liquid hydrocarbon fuels (gasoline and diesel fuel). 

More complex hydrocarbonaceous fuels might materialize in the long term, depending on the alternative vehicle market. The fuel development programs also include hydro-carbonaceous fuels for both, on-board reformers and for liquid hydrocarbon fuel cells. The introduction of hybrid and FC cars would inevitably reduce the share of gasoline in total fuel consumed. 

MDDW [Mobil Distillate DeWaxing] A process for removing waxes (long-chain normal paraffins) from petroleum fractions by cracking over the zeolite ZSM-5. The waxes are converted to liquid hydrocarbon fuels. Twenty one units were operating in 1990. 

Both the production of hydrogen from coal and the production of oil from unconventional resources (oil sands, oil shale, CTL, GTL) result in high C02 emissions and substantially increase the carbon footprint of fuel supply, unless the C02 is captured and stored. While the capture of C02 at a central point source is equally possible for unconventionals and centralised hydrogen production, in the case of hydrogen, a C02-free fuel results, unlike in the case of liquid hydrocarbon fuels. This is all the more important, as around 80% of the WTW C02 emissions result from the fuel use in the vehicles. If CCS were applied to hydrogen production from biomass, a net C02 removal from the atmosphere would even be achievable. 

Elliott, D.C., Schiefelbein, G.F., Liquid hydrocarbon fuels from biomass, Am. Chem. Soc., Div. Fuel. Chem., 1989, 34, 1160. 

In earlier sections of this chapter, the role that particulates play in a given environmental scenario was identified. This section will be devoted exclusively to combustion-generated particulates whose main constituent is carbon. Those carbonaceous particulates that form from gas-phase processes are generally referred to as soot, and those that develop from pyrolysis of liquid hydrocarbon fuels are generally referred to as coke or cenospheres. 

When evaluating the impact to structures, standard fire test exposures can be utilized to determine the onset of critical temperatures or the impact mitigation strategies. Hydrocarbon fire time-temperature exposures have been developed to simulate the rapid temperature rise to approximately 2000°F experienced with liquid hydrocarbon fuel fires. 

An integral part of defining the fire-scenario envelope is determining the appropriate dimensions for use in planning fire protection. For liquid hydrocarbon fuels, a frequently used frame of reference is a fire-scenario envelope that extends 20-40 ft (6-12 m) horizontally, and 40 ft (12 m) vertically, from the source of liquid fuel. For pool or spill fires, the source is generally considered to be the extent of the fire as defined by containment such as dikes and curbs. 

Marchand, A. P. 1989. High-energy-density solid and liquid hydrocarbon fuels. Technical Report AFWAL-TR-88-2128 (Feb.). Distribution unlimited. 

The investigation showed efficient supersonic combustion of a liquid hydrocarbon fuel when using effervescent sprays and elliptic nozzles for the injection of the fuel. In the future, it would be interesting to study the possibilities of supersonic combustion enhancement using the elliptic nozzles drilled at the base of NASA swept wedges. 

Ducted rockets are intermediate between solid rockets and liquid ramjets in their propulsion characteristics. The propulsive force of soHd rockets is generated by the combustion of propellants composed of oxidizer and fuel components. Thus, no additional fuels or oxidizers need to be introduced from the atmosphere into the rocket motor. The momentum change of the exhaust gas from the nozzle attached to the aft-end of the combustion chamber is converted into the thrust for propulsion. On the other hand, the propulsive force of Hquid ramjets is generated by the combustion of a liquid hydrocarbon fuel with air introduced from the atmo-sphere.Ii] jjjg incoming air is compressed by a shock wave formed at the air-intake attached to the front end of the combustor. The air taken in from the atmosphere serves only as the oxidizer for the ramjets. The thrust is created by the momentum difference between the exhaust gas from the combustor and the air taken in from the atmosphere. 

CA 46, 1768 (1952) gives a review of gelled liquid hydrocarbon fuels... 

Catalytic Reforming of Liquid Hydrocarbon Fuels for Fuel Cell Applications... 

Monopropellant drops have been shown to be capable of detonating in a manner similar to liquid hydrocarbon fuels (Ref 11). With monopropellant explosives, energy release per unit volume of explosive is not limited by atmospheric oxygen however, energy release per unit weight is smaller than for fuels using atmospheric oxygen... 

Three types of direct coal liquefaction processes have emerged to convert coals to liquid hydrocarbon fuels 8... 

Also according to Van Dolah ammonium nitrate-oil mixtures offer a certain dust explosion hazard and any electric equipment (switches controls, motors, lights) located in the plant should conform to the safety requirements or should be installed outside the plant. In order not to increase the dust explosion hazard no liquid hydrocarbon fuel with higher volatility than No. 2 Diesel fuel (minimum flash point of 145°F, ASTM closed-cup procedure) should be used as an admixture to ammonium nitrate. More volatile fuels, such as gasoline, kerosine or No. 1 Diesel fuel cannot be recommended according to Van Dolah, as they would seriously increase the hazard of a vapour explosion. 

Liquid Hydrocarbon Fuels Having High Volumetric Energy Content in J33 Single Combustor, Natl. Advisory Comm. Aeronaut. RM E50H28 (1950). 

See, for instance J. E. Sanderson, D. L. Wise and D. G. Augenstein, "Liquid Hydrocarbon Fuels from Aquatic Biomass , Paper No. 27 presented at the Second Annual Fuels from Biomass Symposium, Rensselaer Polytechnic Institute, Troy, New York (June 20-22, 1978). 

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