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The objective of this study was to discuss the possibilitiesto
treat soils contaminated by 2，4-dinitrophenol（2，4-DNP）both
in aerobic and anaerobic conditions. The possibilities to
analyze the nonvolatile organic compoundby using supercritical
fluid extraction （SFE）was alsodiscussed. The experimental
results indicated that SFEcould be effectively used to extract
organics in contaminatedsoils for GC analysis. However , the
efficiency of SFE extraction depended on the choosing the proper
operation condition of SFE（such as temperature and pressure） ,
establishing the extraction efficiency of a series of soils
contaminated by different concentrations of 2，4-DNP by SFE ,
and establishing the calculbration curves for the total amount
of 2，4-DNP in the collected solutions extracted from soils by
SFE. This process also could be used to determine the
bioremediation efficiency of 2，4-DNP contaminated soils.
Comparing the SFE with the traditional soil extraction process ,
the experimental results showed that the extraction time and the
total amount of solvent used in the extraction process could be
minimized. The results of soil bioremediation study showed that
2，4-DNP would be more effectively removed at anaerobic
condition. The results also indicated the indigenous cells
present in soils slowly degrade 2，4-DNP both in aerobic and
anaerobic environments. However , when the concentration of
2，4-DNP was relatively high , such as 20 mg/kg-soil , the
indigenous microorganisms could not effectively biodegrade 2，4-
DNP.The addition of acclimated microorganisms was required to
effectively remove 2，4-DNP at concentrations higher than 20 mg/
kg-soil.
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