1. Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil
- Author
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Nan Li, Xin Wang, Yueyong Zhang, Zhiyong Jason Ren, Xiaojing Li, and Qixing Zhou
- Subjects
Environmental Engineering ,Environmental remediation ,Health, Toxicology and Mutagenesis ,Amendment ,Alcanivoraceae ,complex mixtures ,Soil ,Soil Pollutants ,Environmental Chemistry ,Polycyclic Aromatic Hydrocarbons ,Electrodes ,Soil Microbiology ,chemistry.chemical_classification ,biology ,Denaturing Gradient Gel Electrophoresis ,Chemistry ,Public Health, Environmental and Occupational Health ,Electrochemical Techniques ,General Medicine ,General Chemistry ,Silicon Dioxide ,biology.organism_classification ,Pollution ,Soil contamination ,Biodegradation, Environmental ,Petroleum ,Hydrocarbon ,Environmental chemistry ,Soil water ,Alcanivorax ,Soil microbiology - Abstract
Bioelectrochemical system is an emerging technology for the remediation of soils contaminated by petroleum hydrocarbons. However, performance of such systems can be limited by the inefficient mass transport in soil. Here we report a new method of sand amendment, which significantly increases both oxygen and proton transports, resulting to increased soil porosity (from 44.5% to 51.3%), decreased Ohmic resistance (by 46%), and increased charge output (from 2.5 to 3.5Cg(-1)soil). The degradation rates of petroleum hydrocarbons increased by up to 268% in 135d. The degradation of n-alkanes and polycyclic aromatic hydrocarbons with high molecular weight was accelerated, and denaturing gradient gel electrophoresis showed that the microbial community close to the air-cathode was substantially stimulated by the induced current, especially the hydrocarbon degrading bacteria Alcanivorax. The bioelectrochemical stimulation imposed a selective pressure on the microbial community of anodes, including that far from the cathode. These results suggested that sand amendment can be an effective approach for soil conditioning that will enhances the bioelectrochemical removal of hydrocarbons in contaminated soils.
- Published
- 2015