ISOLATION OF ASPHALTENES USING A CONTINUOUS PRECIPITATION METHOD

ABSTRACT

A new continuous method allows the isolation of heptane asphaltenes which are nearly identical to asphaltenes isolated by a well-studied batch method. Samples of one-half liter of atmospheric resid can be treated using one to two liters of n-heptane, while keeping heptane/resid ratios at 40:1. Asphaltenes precipitated by a well established batch method were identical within the errors of elemental and NMR characterization methods. Small amounts of colored, heptane-soluble materials can be extracted from samples prepared by the continuous technique, but this extraction does not change the analyses of the extracted solids.