Nitrogen compounds, fuels

The reactive species that iaitiate free-radical oxidatioa are preseat ia trace amouats. Exteasive studies (11) of the autoxidatioa mechanism have clearly estabUshed that the most reactive materials are thiols and disulfides, heterocycHc nitrogen compounds, diolefins, furans, and certain aromatic-olefin compounds. Because free-radical formation is accelerated by metal ions of copper, cobalt, and even iron (12), the presence of metals further compHcates the control of oxidation. It is difficult to avoid some metals, particularly iron, ia fuel systems. 

The challenge in these designs is to lower the NO without degradation in unit stability. In the combustion of fuels that do not contain nitrogen compounds, NOx compounds (primarily NO) are formed by two main mechanisms, thermal mechanism and the prompt mechanism. In the thermal mechanism, NO is formed by the oxidation of molecular nitrogen through the following reactions ... 

Many GTL-derived fuels are being considered for blending with gasoline and diesel to achieve emission reductions of particulate matter (PM), carbon monoxide (CO), nitrogen compounds (NOx) and nonmethane hydrocarbons (NMHC). The most promising fuels converted from natural gas are methanol and ethers such as dimethyl ether (DME) and mcthyl-t-bntyl ether (MTBE). 

Excess fertilizer and combustion processes also can increase nitrous oxide (NnO) and nitrogen oxides (NOx) in the atmosphere. Nitrous oxide is a powerful greenhouse gas, and nitrogen oxides lead to smog and acid rain. The production of fertilizers requires a great deal of energy. The use of fossil fuels to supply the thermal requirements for fertilizer production further increases emission of nitrogen compounds to the atmosphere. 

Under similar conditions, nitrogen compounds in the fuel react as follows ... 

Jokuty, P., and Gray, M. R., Resistant Nitrogen Compounds in Hydrotreated Gas Oil From Athabasca, bitumen,. Energy Fuels, 1991. 5 pp. 791-795. 

Other Compounds The effect of other compounds (such as those containing nitrogen) on PAFC performance has been adequately reviewed by Benjamin et al. (35). Molecular nitrogen acts as a diluent but other nitrogen compounds (e.g., NH3, HCN, NOx) may not be as innocuous. NH3 in the fuel or oxidant gases reacts with H3PO4 to form a phosphate salt, (NH4)H2P04,... 

Chemical and Physical Properties Petroleum fuels contain paraffins, isoparaffins, naphthenes, and aromatics, plus organic sulfur, oxygen, and nitrogen compounds that were not removed by refining. Olefins are absent or negligible except when created by severe refining. Vacuum-tower distillate with a final boiling point equivalent to 730 to 840 K (850 to 1050°F) at atmospheric pressure may contain from 0.1 to... 

Bert, P., Bianchini, C., Giambastiani, G., Miller, H., Santiccioli, S., Tampucci, A. and Vizza, E. (2006) Direct fuel cells comprising a nitrogen compounds and... 

Evaluate fuel for nitrogen if >50 ppm, darkening could be originating from organic nitrogen compounds. 

Acid rain Rain or any other form of precipitation that is strongly acidic due to sulfur and nitrogen compounds released through the burning of fossil fuels, particularly coal. 

The primary purpose of the energy conversion facility is the production of liquid or gaseous fuels most of the sulfur will be removed from these products. Liquid fuel streams will be hydro-desulfurized to meet combusion standards, with the sulfur transferred to the gas phase. In the case of oil shale, extensive hydrotreatment will be required to remove the refractory nitrogen compounds from the oil. With this degree of treatment, the sulfur will also be removed. 

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