中东常压渣油热反应过程中沥青质的缔合性变化规律

The aggregating characteristics variation of asphaltenes of Middle East AR (ME-AR) during thermal reaction was studied. The aggregating characteristics of asphaltenes were demonstrated by the values of critical micelle concentrations (cmc). The cmc values of asphaltenes of ME-AR,40mim and 160min thermal reacted samples were 1.35×10-3mol·L-1,1.29×10-3mol·L-1 and 1.45×10-3mol·L-1. The aggregating tendency of asphaltenes was increasing during coke-induction period as thermal reaction going on, and was decreasing after that. Furthermore, the results of cmc showed that the asphaltene molecules were aggregated during VPO MW measurement. But asphaltenes were single when the solution concentrations were less than cmc. Hence the ratio of VPO MW to that gained by surface data of asphaltene solutions can be defined as aggregating parameter. The aggregating parameter was consistent with that of cmc. This paper manifested that asphaltenes tending to aggregating preferred to aggregating and coking during thermal reaction.