Sulfur-and oxygen-containing compounds

NSO s short for nitrogen-, sulfur-, and oxygen-containing compounds. 

The properties and behavior of asphalts are critically dependent on the nature of the constituents, which consist of hydrocarbon and heterocyclic or nitrogen-, sulfur-, and oxygen-containing compounds. Separation of the various asphalt fractions (Table 4) is usually based on their different boiling points, molecular weights, and solubilities in solvents of different polarities. 

The feed hydrocarbons, which come from the FCC or from the etherification unit of a petroleum refinery, usually have to be treated before entering the alkylation unit. They contain water, butadienes, and sulfur- and nitrogen-containing compounds and—when coming from an etherification unit—traces of oxygenates. 

Nirmalakhandan et al. (1997) later applied this estimation method to 105 new chemicals, including oxygen, sulfur, and nitrogen, containing compounds which were not present in the original set. The average factor of error (AFE) was 3.57, with 80% of the estimations being less than an AFE of 3.0. They also developed an estimation method for KAW as a function of absolute temperature in the form of the equation... 

Asphalt fumes are complex mixtures containing numerous organic compounds, PAHs and nitrogen, sulfur and oxygen-containing PAHs in vapor and aerosol form. Asphalt road pavers and highway maintenance workers are exposed to asphalt fumes by both inhalation and skin contact. 

Dianions derived from sulfur and oxygen containing polycyclic systems have not been reported until very recently. The weak carbon-sulfur bond could discourage attempts to prepare such dianions. Sulfur removal studies by alkali metals were successful due to the properties of the carbon-sulfur bond 182,183). Reductive alkylation studies on model compounds which are relevant to sulfur containing systems demonstrated the stability of hydrocarbon dianions 182). A spectroscopic study performed under mild conditions afforded the characterization of sulfur and oxygen containing dianions 184 186). Benzo[b]thiophene, (73), 1,3-diphenylbenzo[c]thiophene (74) and l,3-diphenylbenzo[c]furan (75) form the respective dianions at low temperature. 

In the third step, the hydrotreating step, the sulfur, nitrogen, and oxygen containing compounds are hydrogenated over metallic sulfide catalysts to hydrogen sulfide, ammonia, water and hydrocarbons. Olefins present in the raw shale oil are also hydrogenated. 

Crude petroleum contains complex mixtures of hydrocarbons as well as relatively small amounts of nitrogen-, sulfur-, and oxygen-containing organic compounds, asphaltenes, and various trace metals (uncomplexed and complexed forms). The hydrocarbons can be divided into two classes related to their chemical structure the alkanes (normal, branched, and cyclo) and aromatic compounds (mono-, di-, and poly-, i.e., PAH). 

It should be noted that sulfur- and nitrogen-containing compounds act like the oxygenated materials relative to the solubility of ferric thiocyanate. Acids and oxidizing compounds interfere with the test. 

OMI Oxygen, water, CO, CO2, alcohols/phenols, sulfur- and halogen-containing compounds Argon, helium, nitrogen, hydrogen, argon/methane, neon Yes (color)... 

A 1.1 Technically, the bromine number is the number of grams of bromine reacting with 100 g of the sample under prescribed conditions. By this definition, bromine consumed by addition, substitution, oxidation, and reactions with sulfur, nitrogen, and oxygen-containing compounds is included in the bromine number of the material. The use of the bromine number under determination in the estimation of olefinic unsaturation depends on the fact that the addition reaction proceeds rapidly and completely under most conditions. The addition of bromine proceeds readily at temperatures down to or below 0 C. Decreasing temperature of reaction, time of contact, and concentration of free bromine... 

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