ABSTRACT
Asphaltenes were separated by precipitation with a 40: 1 volume ratio of the n-paraffin (either n-heptane or n-pentane). Mter solvent additon to the sample, the solution was kept at room temperature, under sonication, for 15 minutes; then the asphaltenes were removed by filtration (Millipore System, 0.5 ~m teflon membrane), and dried under vacuum at a temperature of 120 oc till constant weight DAOs were rotary evaporated at a temperature of 60 oc and at reduced pressure, in order to remove the added n-paraffin.
