Test Method for Kauri-Butanol Value of Hydrocarbon Solvents

Standard test method for Kauri-Butanol value of hydrocarbon solvents, ASTM D1133-02, Book of Standards, Vol. 6.04. 

Standard Test Method for Kauri-Butanol Value of Hydrocarbon Solvents,... 

The Kauri-butanol value, used to rate solvency of hydrocarbon solvents, is defined in ASTM Method D 1133 as the volume in milliliters of the hydrocarbon solvent at 25 °C that is required to produce a defined degree of turbidity when titrated into a specified quantity of a standard clear solution of kauri resin in n-butyl alcohol. Kauri-butanol values range from approximately 20 for the weakest hydrocarbon solvents to more than 100 for stronger aromatic solvents. The test is limited to hydrocarbon solvents and is not applicable to oxygenated solvents. As Kauri resin (a natural resin) is no longer easily available, the test has not maintained its acceptance in the industry. Aniline point (or mixed aniline point), another measure of solvency of hydrocarbon solvents, is more accepted. The ani-... 

Kauri-butanol number A measurement of solvent strength for hydrocarbon solvents the higher the Kauri-butanol (KB) value, the stronger the solvency the test method (ASTM D1133) is based on the principle that Kauri resin is readily soluble in butyl alcohol but not in hydrocarbon solvents and that the resin solution will tolerate only a certain amount of dilution and is reflected as cloudiness when the resin starts to come out of solution solvents such as toluene can be added in a greater amount (and thus have a higher KB value) than weaker solvents such as hexane. 

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