Diesel fuel ignition improvers

In a fuel additive use for 2-ethylhexanol, the alcohol is reacted with nitric acid and the nitrate produced added in low concentrations to diesel fuel to improve ignition quality. Use of such a "cetane improver" allows the refiner greater flexibility in blending distillate into fuel such as aromatics, branched paraffins, and naphthenes. The "cetane improver" also helps meet sudden local increases in demand for diesel fuels by allowing refiners to upgrade stored heating oil to diesel fuel quality quickly and economically. 

Poly(thioether)s should not be confused with poly(sulfide)s, in that the term poly refers directly to the sulfide linkage, i.e., —Sn—, but at the same time to a polymer. These types of polymers are used in a completely different field of application, e.g., additives for elastomers, antioxidants for lubricating oils, intermediates for the production of organic chemicals, insecticides, germicides, and as an additive to diesel fuels to improve the octane number and ignition qualities of these fuels. These polymeric types are not dealt with in this chapter. 

Power output is controlled, not by adjusting the quantity of fuel/air mixture as in the case of induced spark ignition engines, but in changing the flow of diesel fuel introduced in a fixed volume of air. The work required to aspirate the air is therefore considerably reduced which contributes still more to improve the efficiency at low loads. 

H. O. Hardenburg, "Comparative Study of Heavy-Duty Engine Operation with Diesel Puel and Ignition-Improved Methanol," Sy4E Paper 872095, SyPE Int. Fuels and Eubricants Meeting andExpo. (Toronto, Canada, Nov. 2—5,1987), Society of Automotive Engineers, Warrendale, Pa. 

IgG (immunoglobulin G), 12 145 Ignition, 7 431-442 acetylene, 1 181-185 acetylene mixtures, 1 186 energy required for, 23 117 sources of, 23 116-118 Ignition improvers, diesel, 12 427 Ignition quality, diesel fuel and,... 

Ignition-Quality Improvers. Diesel fuels have found greatly increased use in recent years—so much so that refiners have had to look to cracked distillates from catalytic cracking operations for their extra Diesel fuels. While these cracked distillates have the advantages of relatively high heat content and low pour point, they are inferior in ignition quality (cetane number) to straight-run distillates from the same crudes. 

Early in 1952, a blend of primary amyl nitrates was introduced commercially as a Diesel ignition improver. This additive is being used by refiners to upgrade distillates which are low in ignition quality (thereby increasing supplies of Diesel fuels), to increase the flexibility of refining operations, and to permit the marketing of diesel fuels of more uniform quality. Steps in its development and its properties have been reported in the literature (1, 18, 38). 

T-M. Li and R.F. Simmons, The Action of Ignition Improvers in Diesel Fuels, 21st Symp. (Int.) Comb. (The Combustion Institute, Pittsburgh, 1986) p. 455. 

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