Specialist Analysis

29/01/2009

Total Base Number (TBN)

Understanding TBN requires some knowledge of fuel sulfur content. Most diesel fuel contains some amount of sulfur. How much depends on the amount of sulfur in the crude oil from which it was produced and/or the refiner's ability to remove it. One of the functions of lubricating oil is to neutralize sulfur by-products, namely sulfurous and su.lfuric acids and thus retard corrosive damage to the engine. Additives (primarily detergents) in the oil contain alkaline compounds which are formulated to neutralize these acids. The measure of this reserve alkalinity in an oil is known as its TBN. Generally, the higher the TBN value, the more reserve alkalinity or acid- neutralizing capacity the oil contains.


Total Acid Number (TAN)

The acid content of lubricating oil is a critical component in mechanisms and rates of corrosion. Acidic compounds are generated when the oil is oxidised especially under heat stress. Sulfur and nitrogen-containing compounds may generate aggressive mineral acids (sulfuric and nitric acid) and related corrosive compounds. Oil manufacturers incorporate non-acidic (base or basic) compounds, known as an alkaline reserve, in the lubricant to neutralise the acidic compounds and to mitigate their concentration and effects.The TAN is a measure of the un-neutralised acidic content of a petroleum product.  


Metallic Alloy Constituent Analysis (MACA)

This test method covers the procedures to determine the composition of samples of metallic alloys by dissolving small pieces of the alloy in acids and analysing the resultant solution by ICP spectrophotometer.
The composition of a metallic particle may be of assistance in identifying the source of that particle in a machine particularly if a specimen of the suspected source is also available for analysis. This technique is most successful where relatively large pieces of metal are recovered which can be handled easily and digested separately.


Moisture Content by Karl Fischer Titrator
Karl Fischer titration is a classic titration method in analytical chemistry that uses coulometric titration to determine trace amounts of water in a sample.