Rapid degradation of long-alkanes by
mild Fe-SOM pre-oxidation in soils.
JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023;
342:118291. [PMID:
37270979 DOI:
10.1016/j.jenvman.2023.118291]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/14/2023] [Accepted: 05/27/2023] [Indexed: 06/06/2023]
Abstract
In this study, a novel mild pre-oxidation mode was successfully explored by fabricating Fe-SOM prepared by adding 2.5% and 20% fulvic acid (FA). This study explored the mechanism of mild Fe-SOM pre-oxidation to stimulate rapid biological degradation of long-alkanes in oil-contaminated soils. Results showed that under mild Fe-SOM pre-oxidation, the total •OH intensity and bacterial killing degree(D) were low, and hydrocarbon conversion(C)was fast, resulting in rapid degradation of long-alkanes. Additionally, the fast group removed 1.7-fold more than slow group and biodegraded long-alkanes 182 days significantly faster. Furthermore, compared with slow group (8.26 log CFU/g), the fast group (51.48 log CFU/g) characterized much more bacteria. Besides, the fast group had higher C (5.72%-15.95%), thus increasing the degradation rate of long-alkanes (7.61%-18.86%). A shift in the microbial community was found after mild Fe-SOM pre-oxidation, with an average relative abundance of 18.6% for the dominant genus Bacillus. Therefore, the mild pre-oxidation reduced the D, and the high bacterial abundance promoted nutrients consumption and C, which shortened bioremediation period and increased the long-alkanes degradation rate. This study provided a promising novel mild Fenton pre-oxidation mode to rapid remediate heavily multicomponent oil-contaminated soils.
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