ABSTRACT
Solvent deasphalting (SDA) processes are a major part of refinery operations and are not often appreciated for the tasks for which they are used (Bland and Davidson, 1967; Hobson and Pohl, 1973; Speight and Ozum, 2002; Hsu and Robinson, 2006; Gary et al., 2007; Speight, 2011). In the solvent deasphalting processes, an alkane is injected into the feedstock to disrupt the dispersion of components and causes the polar constituents to precipitate. Propane (or sometimes propane/butane mixtures) is extensively used for deasphalting and produces a deasphalted oil (DAO) and propane deasphalter asphalt (PDA or PD tar) (Dunning and Moore, 1957). Propane has unique solvent properties; at lower temperatures (38°C-60°C; 100°F-140°F), paraffins are very soluble in propane, and at higher temperatures (about 93°C; 200°F), all hydrocarbons are almost insoluble in propane.
