title: Sand amendment enhances bioelectrochemical remediation of petroleum hydrocarbon contaminated soil.
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.
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Li
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address: xinwang1@nankai.edu.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO 80309, USA.
authors.forename: Zhiyong Jason
authors.initials: ZJ
authors.lastname: Ren
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Yueyong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address: zhouqx@nankai.edu.cn.
authors.forename: Qixing
authors.initials: Q
authors.lastname: Zhou
mesh_terms: D053521:Alcanivoraceae / Q000254:growth & development; D001673:Biodegradation, Environmental; D058645:Denaturing Gradient Gel Electrophoresis; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D010578:Petroleum / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012822:Silicon Dioxide / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D012822:Silicon Dioxide
keywords: Bioelectrochemical remediation; Hydrocarbon contaminated soils; Internal resistance; Mass transport; Microbial community