Fully continuous supercritical fluid extraction of naphthalene from soil slurries
The objective of this research was to design, build and test a fully continuous labscale supercritical fluid extraction (SFE) system to remove naphthalene from soil slurries. Delhi Loamy Sand, spiked with 10 mg/g of naphthalene, was used during experiments. The soil content in the slurry was 0.3% for all but the last experiment which went up to 7%. The temperature of the CO 2 was around 43°C while the pressures ranged between 5.6 to 7.9 MPa. A first level of success was reached since the two fluids, CO2, and a soil slurry flowed continuously into the vessel. Mass transfer coefficients as high as 4.6 * 10-4 s-1 were achieved with the system and increased soil content increased the naphthalene removal. A cost-benefit analysis should be performed to evaluate whether a full-scale system would be feasible.