The dissolving capacity of DDT played a major role in DDT removal efficiency by foam flushing under laboratory conditions.
The DDT removal contributions of improving sweep efficiency for heterogeneous patterns 1 and 2 by foam flushing were 40.82% and 45.98%, and the contribution of dissolving capacity were 59.18% and 54.02%, respectively.
As the oxygen atoms were bonded to the sulfur atoms, dipole moment of the sulfur compounds increased accordingly, and thus their dissolving capacity in the polar solvents (DMF, DMSO, etc.,) was enhanced significantly.
The oxygen dissolving capacity of Oxycyte® is (43) vol% (43 ml O2/100 ml pure PFC) at 37°C and 760 mmHgO2.
PFCs have been used clinically as blood substitutes because of their high gas dissolving capacity for oxygen and carbon-dioxide as well as their chemical and metabolic stability [8].
EG is a polar solvent with a high boiling point (approximately 198°C) and a high permittivity of 37 at 20°C, which is believed to have a high dissolving capacity for polar inorganic materials.
This was also observed in our investigation, where SFE extracts did not show any significant antioxidant activity and neither did the hexane extracts, which is expected, since CO2 and hexane possess a similar dissolving capacity.
These compounds are characterized by a high gas dissolving capacity (O2, CO2, inert gas), low viscosity, chemically and biologically inert (Spahn 2000).
The superior dissolving capacity of [C2mim]OAc has also been reported by Sun et al. [ 14] who measured 93.5% dissolution extent of southern yellow pine in [C2mim]OAc and only 26% in [C4mim]Cl under the same conditions (particle size 0.25 – 0.50 mm, 5% mass loading, 110°C for 16 h).
This can be explained by similar dissolving capacity of supercritical CO2 and n-hexane because both are non-polar solvents, dissolving non polar compounds only, while ethanol as a polar solvent dissolved the whole soluble polar compounds.
