The permeable reactive barrier（PRB） has proven to be a costeffective technique to remediate the petro leum contaminated groundwater at a northeast field site in China. In this study, the geology, hydrogeology and co...The permeable reactive barrier（PRB） has proven to be a costeffective technique to remediate the petro leum contaminated groundwater at a northeast field site in China. In this study, the geology, hydrogeology and con tamination characterization of the field site were investigated and the natural hydrothermal palygorskite was chosen as a reactive medium. Furthermore, the adsorption of the total petroleum hydrocarbons（TPH） in the groundwater onto hydrothermal palygorskite and the adsorption kinetics were investigated. The results indicate that the removal rates of TPH, benzene, naphthalene and phenantharene could all reach up to 90% by hydrothermal palygorskite with a diameter of 0.25-2.00 mm that had been thermally pretreated at 140 ℃. The adsorption of TPH onto hydrothermal palygorskite after pretreatment followed a pseudosecondorder kinetic model and a Langmuir adsorption isotherm, suggesting that the theoretic adsorption capacity of hydrothermal palygorskite for adsorbate could be 4.2 g/g. Scan ning electron microscopy（SEM）, infrared spectroscopy（IR）, Xray diffraction（XRD） and Xray fluorescence spec troscopy（XRF） were carried out to analyze the adsorption mechanism. The results reveal that hydrothermal palygors kite is a fibrous silicate mineral enriched in Mg and A1 with large surface area and porosity. The dense cluster acicular and fibrous crystal of hydrothermal palygorskite, and its effect polar group OH played an important role in the physical and chemical adsorption processes of it for contaminants. This study has demonstrated hydrothermal paly gorskite is a reliable reactive medium for in situ remediation of petroleum contaminated groundwater at field sites.展开更多
In this study, we compared plant height, weight, soil TPH concentration, and soil DHA level after 18 weeks of </span><i><span style="font-family:Verdana;">Zennia</span></i><s...In this study, we compared plant height, weight, soil TPH concentration, and soil DHA level after 18 weeks of </span><i><span style="font-family:Verdana;">Zennia</span></i><span style="font-family:Verdana;"> <i>hybrida</i> </span><span style="font-family:Verdana;">cultivation with four different concentrations of 5-Aminolevulinic acid (ALA)-based liquid fertilizer: 1500-fold, 5000-fold, and 8000-fold dilutions, along with a non-treatment control of diluted ALA. The plants of ALA-treated were significantly taller than the non-treatment control. The plants of ALA-treated plants were higher in shoot fresh weight, shoot dry weight, and root dry weight than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold dilution was significantly highest in shoot fresh weight, shoot dry weight, and root dry weight. ALA-treated plants were lower in the soil Total Petroleum </span></span><span style="font-family:Verdana;">Hydrocarbon </span><span style="font-family:""><span style="font-family:Verdana;">(TPH) concentration than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was significantly lowest in the TPH concentration. In addition, ALA-treated plants were </span><span style="font-family:Verdana;">higher in the soil dehydrogenase activity (DHA) than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was signifi</span><span style="font-family:Verdana;">cantly highest in the TPH concentration. This study indicated that ALA-applied zinnia-grown oil-contaminated soil is more effective than not. The remediation in oil-contaminated soil with ALA-based liquid fertilizer is more effective than the non-treatment control</span></span><span style="font-family:Verdana;">;</span><span style="font-family:Verdana;">furthermore, ALA application with 5000-fold dilution was most suitable in oil-contaminated soil among other plots.展开更多
文摘The permeable reactive barrier（PRB） has proven to be a costeffective technique to remediate the petro leum contaminated groundwater at a northeast field site in China. In this study, the geology, hydrogeology and con tamination characterization of the field site were investigated and the natural hydrothermal palygorskite was chosen as a reactive medium. Furthermore, the adsorption of the total petroleum hydrocarbons（TPH） in the groundwater onto hydrothermal palygorskite and the adsorption kinetics were investigated. The results indicate that the removal rates of TPH, benzene, naphthalene and phenantharene could all reach up to 90% by hydrothermal palygorskite with a diameter of 0.25-2.00 mm that had been thermally pretreated at 140 ℃. The adsorption of TPH onto hydrothermal palygorskite after pretreatment followed a pseudosecondorder kinetic model and a Langmuir adsorption isotherm, suggesting that the theoretic adsorption capacity of hydrothermal palygorskite for adsorbate could be 4.2 g/g. Scan ning electron microscopy（SEM）, infrared spectroscopy（IR）, Xray diffraction（XRD） and Xray fluorescence spec troscopy（XRF） were carried out to analyze the adsorption mechanism. The results reveal that hydrothermal palygors kite is a fibrous silicate mineral enriched in Mg and A1 with large surface area and porosity. The dense cluster acicular and fibrous crystal of hydrothermal palygorskite, and its effect polar group OH played an important role in the physical and chemical adsorption processes of it for contaminants. This study has demonstrated hydrothermal paly gorskite is a reliable reactive medium for in situ remediation of petroleum contaminated groundwater at field sites.
文摘In this study, we compared plant height, weight, soil TPH concentration, and soil DHA level after 18 weeks of </span><i><span style="font-family:Verdana;">Zennia</span></i><span style="font-family:Verdana;"> <i>hybrida</i> </span><span style="font-family:Verdana;">cultivation with four different concentrations of 5-Aminolevulinic acid (ALA)-based liquid fertilizer: 1500-fold, 5000-fold, and 8000-fold dilutions, along with a non-treatment control of diluted ALA. The plants of ALA-treated were significantly taller than the non-treatment control. The plants of ALA-treated plants were higher in shoot fresh weight, shoot dry weight, and root dry weight than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold dilution was significantly highest in shoot fresh weight, shoot dry weight, and root dry weight. ALA-treated plants were lower in the soil Total Petroleum </span></span><span style="font-family:Verdana;">Hydrocarbon </span><span style="font-family:""><span style="font-family:Verdana;">(TPH) concentration than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was significantly lowest in the TPH concentration. In addition, ALA-treated plants were </span><span style="font-family:Verdana;">higher in the soil dehydrogenase activity (DHA) than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was signifi</span><span style="font-family:Verdana;">cantly highest in the TPH concentration. This study indicated that ALA-applied zinnia-grown oil-contaminated soil is more effective than not. The remediation in oil-contaminated soil with ALA-based liquid fertilizer is more effective than the non-treatment control</span></span><span style="font-family:Verdana;">;</span><span style="font-family:Verdana;">furthermore, ALA application with 5000-fold dilution was most suitable in oil-contaminated soil among other plots.
