Oxygen materials

Oxygenates. Oxygenated materials have been considered for addition to diesel fuels for the same reasons these compounds ate added to... 

The composition of an oxidizing mixture is altered extensively by the passage of a cool flame (66,83,84). Before passage of the flame, oxygenated materials are present. In the case of hexane oxidation, ROO radicals are reportedly displaced by HOO radicals above 563 K (85), in concordance with previous work (86,87). After the passage of a cool flame, olefins, some conjugate and others of lower molecular weight, are observed. 

Effect of Pressure. The effect of pressure in VPO has not been extensively studied but is informative. The NTC region and cool flame phenomena are associated with low pressures, usually not far from atmospheric. As pressure is increased, the production of olefins is suppressed and the NTC region disappears (96,97). The reaction rate also increases significantly and, therefore, essentially complete oxygen conversion can be attained at lower temperatures. The product distribution shifts toward oxygenated materials that retain the carbon skeleton of the parent hydrocarbon. 

Although fluonnation of peroxoanions [S2] has been examined, the major emphasis in the fluonnation of oxygenated material is the preparation offhioroxy compounds The simplest, trifluoromethyl hypofluorite, can be prepared almost quantitatively by the action of fluorine on carbonyl fluoride (fluorophosgene) in the presence of various catalysts [Si, 84] Addition of fluorine to trifluoroacetic acid [S5] or its sodium salt [S6] gives rise to FjCF(OF)2 Long-chain fluoroxy compounds can also... 

Oxygen-containing impurities such as phenols and naphthenic acids can adversely affect water separation properties and initiate gum formation. No limit presently exists to control the amount of oxidized organic compounds found in jet fuel. However, tests for existent gums, neutralization number, and water separation indirectly limit the presence of oxygenated materials in jet fuel. 

P. Kritzer, N. Bonkis, E. Dinjus, The Corrosion of Alloy 625 (NiCr22Mo9Nb 2.4856) in High-Temperature, High-Pressure Aqueous Solutions of Phosphonic Acid and Oxygen, Materials and Corrosion, 49, (1998), 1. 

However, Natta, Pasquon, Zambelli and Gatti (63) have shown that titanium trichloride-dialkylaluminum chloride or titanium trichloride and alkylaluminum dichloride with nucleophilic materials are good catalysts for the polymerization of propylene to the isotactic structure. The titanium trichloride could also be made in situ from titanium tetrachloride and triethyl aluminum. Vesely, Ambroz, Vilin and Hamrik (64) showed the addition of the nucleophilic materials to diethylaluminumchloride-titanium trichloride polymerizations decreased the rate of polymerization and changed the stereospecificity. The more nucleophilic materials such as sulfur compounds were more effective than the less nucleophilic oxygen materials. 

Dimethyl carbonate is an interesting material which can be used instead of toxic dimethyl sulfate as a multipurpose alkylating reagent.438-578 Its synthesis can be performed in one step from cheap methanol, CO and oxygen materials in the presence of copper salts (e.g. copper(ll) methoxychloride or CuCl/py) at ca. 100 °C and 15-70 atm (equation 290).578,62S This reaction is thought to proceed in two steps 578 (a) formation of copper(II) methoxychloride from the reaction of copper(I) chloride, 02 and methanol (equation 291) and (b) reduction of copper(II) methoxychloride with CO to form dimethyl carbonate and regenerate copper(I) chloride (equation 292).626... 

Acid Fractions. The acid contents, as shown in Table V, account for about 0.4 to 0.6 percent of the 325° to 425° C coal liquid distillates except for the lignite liquid (0.76). The acid content for the 425° to 540° C distillates mostly fall in the range of 0.50 to 0.59 percent except for Pittsburgh (0.29) and Wyodak run 1 (0.34). The total acids from the 325° to 425° C and the 425° to 540° C distillates plus the oxygenate material from the 200° to 325° C distillate (19) expressed on a total liquid basis, correlated fairly well with the total coal liquid oxygen content (Table II) (correlation coefficient 0.82). The data are plotted in Figure 5. 

It also can be produced directly from natural gas, methane, and other aliphatic hydrocarbons, but this process yields mixtures of various oxygenated materials. Because both gaseous and liquid formaldehyde readily polymerize at room temperature, formaldehyde is not available in pure form. It is sold instead as a 37 percent solution in water, or in the polymeric form as paraformaldehyde [HO(CH20)nH], where n is between 8 and 50, or as trioxane (CH20)3. The greatest end use for formaldehyde is in the field of synthetic resins, either as a homopolymer or as a copolymer with phenol, urea, or melamine. It also is reacted with acetaldehyde to produce pentaerythritol [C(CH2OH)4], which finds use in polyester resins. Two smaller-volume uses are in urea-formaldehyde fertilizers and in hexamethylenetetramine, the latter being formed by condensation with ammonia. 

The objectives of the ongoing work is to explore the chemical synthesis of possible replacements for AP as an oxidizer in tactical missile rocket motors. The synthesis, sensitivities, thermal stability, binder compatibility and decomposition pathways of these new high-oxygen materials are currently being researched. In the following example, we theoretically want to evaluate, the suitability of nitrosyl (N0+) and nitronium (NCB,) oxalate as a potential ingredient for solid rocket propellants. 

Acid-labile Oxygenated Metabolite. The 2° alcohol metabolite (Figure 1, R2=0H) was first Isolated in moderate yield from the ethyl acetate phase after solvent partitioning ( 6). Because yields of the free 2° alcohol in this phase sometimes were observed to Increase when the partitioning steps were delayed, decomposition of an unstable polar metabolite may release this oxygenated material. 

Phosgene is reported to combine with a wide range of oxygenated materials, including alcohols, ethers, ketones, carboxylic acids, anhydrides, lactones, esters, carbonic acid derivatives, etc. Only the reactions of COCIF with alcohols, phenols and cyclic ethers have been reported, resulting usually in the generation of fluoroformates. Such materials can often be usefully converted into the corresponding fluoro compound by means of decarboxylation in the presence of BF3, EtjO, pyridine, or other materials. 

Oxygen — A chemical element of atomic weight 16, which at normal atmospheric temperatures and pressures exists as a colorless, odorless, and tasteless gas. Oxygen comprises about 21% by volume of the Earth s atmosphere. Refer to an industrial gas supplier s Oxygen Material Safety Data Sheet (MSDS) for further details. 

A model for calculating viscosities of concentrated polymer solutions has been formulated and used successfully to predict viscosities of alkyd resin solutions in both pure aromatic solvents and in mixtures of hydrocarbons and oxygenated materials. It was also found to describe viscosity trends in polystyrene-diethylbenzene solutions accurately. The formulation explicitly accounts for the observation that concentrated solution viscosities increase markedly with decreasing compatibility between resin and diluent. The proposal of an empirical relationship which interprets the viscosity enhancement in poorer solvents in terms of increased chain-chain interactions is of interest. The model contains three constants which are fixed for a particular resin and are independent of diluent type. These are the Mark-HouuAnk constant, the parameter in the Martin viscosity equation, and the constant relating the postulated clustering to the solution thermodynamics of a particular solution. 

Figure 2 shows the 45 solvents ranked with respect to N02 t-max. The solvents are ranked from highest reactivity to the lowest. Two olefinic materials are the most reactive (Figure 2) followed by two aromatics, mesitylene and m-xylene. Further down the list as reactivity decreases oxygenated materials appear at the lower end of the reactivity scale, and the ketones and esters show up as the least reactive in terms of N02 f-max. 

By using the dynamic technique [20], the kifl value for the oxygen transfer during a fermentation process can be estimated. This technique is based on the oxygen material balance in an aerated batch bioreactor while microorganisms are actively growing as... 

The aromatic constituents of raw lubricant distillate are of little direct interest to the lubrication engineer except for that portion which is not removed from the lubricating oil by commercial extraction or other processing. The character of this material is shown in some detail in Table 16-9. Organosulfur, organonitrogen and oxygenated material tends to go with the aromatic fractions (see Tables 16-3 and 16-9). Mair and Martinez-Pico [14] isolated and identified 4-methyldibenzothiophene, 4,6-dimethyldibenzothiophene and benzo[b]naphtho[2,1-d]-thiophene. Mil hailov and co-workers [15] reported the presence of 1.5-2.7% of benzothiophenes in Russian 100 VI lubricating stocks of 0.85-0.92% sulfur content. 

By assuming that equilibrium exists between the erythrocytes and plasma, the three-lump model is reduced to two lumps. The system equations for the tissue lump-capillary lump model are developed by writing oxygen material balances for the tissue and capillary separately or by summing the erythrocyte and plasma equations for the three-lump model. The two-lump model (21) has been used in this investigation and can be represented by the following set of equations (Figure 1). 

The Synol and isosynthesis processes, as well as the Oxyl and iron nitride variations of the Fischer-Tropsch synthesis, were developed to produce special products from synthesis gas. All but the isosynthesis are designed to produce high yields of oxygenated materials. The isosynthesis yields highly branched aliphatic hydrocarbons and aromatics. While none of these processes has been used commercially, they could be of interest at some future time. 

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