STUDY OF EXTRACTION PROCESS UTILIZING SUPERCRITICAL FLUID FOR CHLORINATED AROMATIC HYDROCARBONS

摘要

The supercritical fluid extraction (SFE) of chlorinatedrnaromatic hydrocarbons is investigated by governing arnvariety of interrelated parameters, including pressure,rntemperature and velocity of fluid. Based on supercriticalrnfluid extraction technology to extract chlorinated aromaticrnhydrocarbons, the optimum extraction parameters arernestablished and compared with the results of Soxhlet. Thernresult shows the optimal extraction parameters at 250 barrnof pressure, 40 degree centigrade of temperature, and 2.0rnmL/min for the fluid flow rate. For the influence ofrnsolvent experiment, the high recovery of 2-5 ringsrnchlorinated aromatic hydrocarbons is applied to n-Hexanernand Dichloromethane by the ratio 1:1 andrnDichloromethane. Furthermore, it is found that SFE has arnhigher recovery percentage than Soxhlet for 2 ringsrnchlorinated aromatic hydrocarbon. Regarding to the timernconsuming, the SFE with 1-5 rings chlorinated aromaticrnhydrocarbons are found to be the faster than Soxhlet.rnAdditionally, the recovery percentage of compounds arernbetween 67.55～89.27 % and 71～112.8 % for 8270rnPhenols Mix and TCL Polynuclear AromaticrnHydrocarbons Mix, respectively. Based on these results,rnthe SFE is proved to be a better and feasible extractionrntechnology for volatile and semi-volatile organicrncompounds.