Cold extraction using a centrifuge extractor method

/ Cold extraction using a centrifuge extractor method 

The cold extraction method using a centrifuge extractor (centrifugal filter paper method) is perhaps the most common method worldwide for the determination of the soluble binder content. 

The extraction is conducted using an extraction apparatus consisting of a bowl with a capacity of 1500 or 3000 g, with a safety cover, and an apparatus in which the bowl may be revolved at controlled variable speeds up to 3600 revolutions per minute (rpm). Additionally, the apparatus is provided with a container for catching the solvent thrown from the bowl, a drain for removing the solvent and an appropriate mechanical brake to stop the device turning. 

A sufficient asphalt test portion (Table 9.6) is weighted and placed in the bowl. The test portion is then fully covered with an appropriate solvent and sufficient time is allowed for the solvent to disintegrate the mixture (not longer than 1 h). A dry filter ring, after its mass has been determined, is placed around the edge of the bowl and then the cover is clamped tightly on the bowl. 

The mass of the test portion, M, can alternatively be determined by weighing first the bowl and the filter ring together, mass and then by weighing the bowl, the filter paper and the added test portion altogether, mass Mg thus, the mass of the test portion, M, is equal to Mg - 

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