SUPERCRITICAL EXTRACTION OF HEXACHLOROBENZENE FROM SOIL

Feasibility of supercritical extraction of hexachlorobenzene from soil by CO2 is investigated. A dynamic tracer response technique is employed to measure the adsorption equilibrium and rate at the temperature range 298-323 K and pressure range 1200-4000 psia at CO2 flow rates of 120-160 mL/h. Thermodynamic consistency of the adsorption equilibrium constants is verified through isochoric temperature dependency and isothermal density dependency of the equilibrium constants. Overall mass transfer coefficients and axial dispersion coefficients are also determined at the experimental conditions.