In vitro: |
Ind. Eng. Chem. Res. 2010, 49, 19, 8908–8919. | TiO2-Coated Cenospheres as Catalysts for Photocatalytic Degradation of Methylene Blue, p-Nitroaniline, n-Decane, and n-Tridecane under Solar Irradiation.[Reference: WebLink] | Biostimulation based on usage of soil amendments is growing due to their efficiency in removing different petroleum hydrocarbons (PHC) from contaminated sand or loam-sand soils.
However, the research on clay-rich soils with higher organic carbon content, in which PHC biodegradation may proceed differently and which are more difficult to clean up, has been less extensive. METHODS AND RESULTS: In a pot experiment, we studied and compared the effects of two soil amendments, natural zeolite-containing material (ZCM, 50 g kg−1) as a bulking agent and ammonium nitrate (0.3 g N kg−1) as a nitrogen fertilizer, on biodegradation of n-Tridecane (1 wt.%) in a weakly acidic heavy clay loam leached chernozem with fairly high organic carbon content (3.71%). After 48 days, the nitrogen-amended contaminated soil showed enhancement of both respiratory activity (basal and substrate-induced respiration rates) and the number of n-Tridecane- degraders. As a consequence, the extent of n-Tridecane biodegradation (86.5%) was essentially higher in the presence of added nitrogen than that in the non-amended soil (73.7%). In contrast, due to the partial retention of n-Tridecane molecules in its pores, ZCM retarded biodegradation to 56.0%, showed no significant effect on the number of n-Tridecane-degraders and, moreover, enhanced the decomposition of the soil intrinsic organic matter.
CONCLUSIONS:
The obtained data indicate that more precautions should be considered when using porous sorbents such as ZCM for remedial arrangements in PHC-contaminated soils. |
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