Neutralization number

Neutralization number (ASTM D-974, IP 139 IP 182) is a measure of the inorganic and total acidity of the unused fuel and indicates its tendency to corrode metals with which it may come into contact. 

Corrosivity is also determined by a variety of copper corrosion text methods (ASTM D-130, ASTM D-849, IP 154). 

The pour point (ASTM D-97, IP 15) of a fuel is an indication of the lowest temperature at which the fuel can be pumped. Pour points often occur 8-10°F below the cloud points, and differences of 15-20°F are not uncommon. Fuels, and in particular those fuels that contain wax, will in some circumstances flow below their tested pour point. However, the pour point does give a useful guide to the lowest temperature to which a fuel can be cooled without setting. 

The maximum and minimum pour point temperatures provide a temperature window where petroleum, depending on its thermal history, might appear in the liquid as well as the solid state. Pour point data can be used to supplement other measurements of cold flow behavior, and the data are particularly useful for the screening of the effect of wax interaction modifiers on the flow behavior of petroleum. 

In the original (and still widely used) test for pour point (ASTM D-97, IP 15), a sample is cooled at a specified rate and examined at intervals of 3°C (5.4°F) for flow characteristics. The lowest temperature at which the movement of the oil is observed is recorded as the pour point. 

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An example of an appHcation of hydrocracking is in lubricating oils, where it is used to improve the viscosity index, color, and color stabiHty to reduce polymer formation (storage stabiHty) and to decrease the neutralization number (acidity) (61). 

An oil sample should be withdrawn from the system and analyzed in the laboratory. The usual tests of the used oil include (1) viscosity, (2) pH and neutralization number, and (3) precipitation. The test results will... 

As a part of the lubrication program, oil should be periodically tested. The testing requires drawing oil from the system for a laboratory analysis. The usual tests conducted to determine the condition of oils include viscosity, pH and neutralization number, precipitation, color and odor, and a check for foreign particles in the oil. The results should be reviewed and compared with new oil characteristics to determine the life characteristics of the oil. 

Naphthenic acid is a collective name for organic acids present in some but not all crude oils. In addition to true naphthenic acids (naphthenic carboxylic acids represented by the formula X-COOH in which X is a cycloparaffin radical), the total acidity of a crude may include various amounts of other organic acids and sometimes mineral acids. Thus the total neutralization number of a stock, which is a measure of its total acidity, includes (but does not necessaiily represent) the level of naphthenic acids present. The neutralization number is the number of milligrams of potassium hydroxide required to neutralize one gram of stock as determined by titration using phenolphthalein as an indicator, or as determined by potentiometric titration. It may be as high as 10 mg KOH/gr. for some crudes. The neutralization number does not usually become important as a corrosion factor, however, unless it is at least 0.5 mg KOH/gm. 

Theoretically, corrosion rates from naphthenic acids are proportional to the level of the neutralization number of feed stocks but investigators have been unable to find a precise correlation between these factors. Predicting con osion rates based on the neutralization number remains uncertain. Published data, however, indicate a scattered trend toward increasing corrosion with increasing neutralization number.-... 

Neutralisations-wirme, /. heat of neutralization. -zahl,/. neutralization number, neutralisleren, v.t. neutralize. 

N.Z., abbrev. (Normalzeit) standard time (Neutralisationszahl) neutralization number. 

Other properties of interest are carbon residue, sediment, and acidity or neutralization number. These measure respectively the tendency of a fuel to foul combustors with soot deposits, to foul filters with dirt and rust, and to corrode metal equipment. Cetane number measures the ability of a fuel to ignite spontaneously under high temperature and pressure, and it only applies to fuel used in Diesel engines. Typical properties ol fuels in the kerosene boiling range are given in Table 1. 

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. 

Fuel acid number or neutralization number is a measure of the acidity or basicity of fuel. The presence of acidic compounds can indicate a fuel stability or oxidative degradation problem. Acidic organic compounds can react with other fuel components to initiate the formation of higher-molecular-weight, fuel-insoluble... 

Neutralization Number The amount of acid or base required to neutralize all components present. 

Neutralization number the weight, in milligrams, of potassium hydroxide needed to neutralize the acid in 1 g of oil an indication of the acidity of an oil. 

Polymer Neutralization Number. A sample of polymer was weighed to the nearest 0.1 mg. (sample sizes of 0.5-1.0 gram). The polymer was dissolved in tetrahydrofuran and if necessary warmed on a steam bath. The solution was titrated with standard potassium hydroxide in methanol using phenolphthalein as indicator. Calculation ... 

Organic acids (e.g., naphthenic acid) can cause severe corrosion above -450 F (230 C) (although attack has been seen as low as 340 F [170 C] in turbulent areas) if the neutralization number exceeds 2.0 mg of potassium hydroxide per gram (mg KOH/g). The naphthenic acid content is generally determined by... 

For naphthenic acid containing hydrocarbons (Table A-4) where the neutralization number of the feed exoeeds 2 mg of KOH/g in a crude unit or 0 5 mg of KOH/g In a vacuum unit, use type 316L (UNS S31603) SS (2.5% Mo minimum) above 450°F (23°C) regardless of sulfur content. For castings, 316 (CF8M) with 2.5% Mo minimum may be used provided the ferrite content is 8% minimum. 

Use type 316L (UNS S31603) SS (2.5% Mo minimum) cladding In vacuum column only when neutralization number exceeds 0.5 mg KQH/gm, Use type 316L SS (2,5% Mo minimum) In the crude column as well when the neutralization number exceeds 2,0 mg KQH/gm,... 

Some characteristics of the homopolymers and copolymers used in this study are shown in Table I percent acid content, percent neutralization, number-average molecular weight (Mn), polydispersity index (Mw/Mn) and the nomenclature used. 

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