The effect of chemical properties of different Iranian crudes on the bitumen producing process

Two different asphaltenes from different sources of crude are characterized using variety of techniques like FT-IR, 1H and 13C NMR, elemental and thermogravimetric analysis. These asphaltenes are seperated from heaviest part of crude (Vacuum Bottom,VB) by precipitation with n-heptane. Then two paving grade bitumen were produced by these Vacuum Bottoms through blowing process. All the parameters of the processes and two products were compared. The results showed that although these asphaltenes are isolated from different oil reservoirs, they have almost the same chemical structure. Almost the same number of carbon atoms per aliphatic side chains, the aromaticity factor, carbonyl index and the same sulphur compounds can be found in these asphaltenes. However, the thermal stabilities of these asphaltenes are not the same. Also the only different between two processes which led to the same product was the result of the amount of asphaltene in the two Vacuum Bottoms.