• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.128-131
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• 2003

To clarify the effect of soil property on the EK-Fenton remediation of the soil contaminated with phenanthrene, this research had been conducted. In the experiments using EPK kaolinite, the $H_2O$$_2$ stability and effect of phenanthrene treatment improved more than that in the experiments using Hadong clayey soil. The results signify that Fe oxide content and acid buffer capacity significantly affected the fate of $H_2O$$_2$ and phenanthrene during the EK-Fenton process.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.11-17
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• 2005

Characteristics of phenanthrene removal in the Electrokinetic (EK)-Fenton process were investigated in a 2-dimensional test cell in a viewpoint of the effect of gravity and electrosmotic flow (EOF). When the constant voltage of 100 V was applied to this system, the current decreased from 1,000 to 290 mA after 28 days, because soil resistance increased due to the exhaustion of ions in soil by electroosmosis and electromigration. Accumulated EOF in two cathode reservoirs was 10.3 L and the EOF rate was kept constant for 28 days. At the end of operation, the concentration of phenanthrene was observed to be very low near the anode and increased in the cathode region because hydrogen peroxide was supplied from anode to cathode region following the direction of EOP. Additionally, the concentration of phenanthrene decreased at the bottom of the test cell because the electrolyte solution containing hydrogen peroxide was largely transported toward the bottom due to a low capillary action in the soil with high porosity. Average removal efficiency of phenanthrene by EK-Fenton process was 81.4% for 28 days. In-situ EK-Fenton process would overcome the limitations of conventional remediation technologies and effectively remediate the contaminated sites.

• Resources Recycling
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• v.15 no.3 s.71
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• pp.58-65
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• 2006

The applicability of the waste pulp which produced in the paper recycling process as an adsorbent for the treatment of $Ni^{2+}$ ion in wastewater has been investigated taking the initial concentration of adsorbate, temperature, the amount of adsorbent, and solution pH as the experimental variables. In addition, the effect of the concentration of coexisting solute and pre-treatment of adsorbent on the adsorbability of $Ni^{2+}$ ion were also examined. The electrokinetic potential of waste pulp was observed to be positive below pH 7.8 and negative above this pH. The adsorption reaction of $Ni^{2+}$ ion reached its equilibrium within 4 hours after the reaction was initiated and the adsorbed amount of adsorbate was found to increase with its initial concentration. The adsorbability of $Ni^{2+}$ was raised with temperature so that its adsorption reaction was considered to be exothermic, which was substantiated by thermodynamic calculation. Also, the adsorbed amount of $Ni^{2+}$ was raised with the amount of waste pulp and with pH in the range of pH $3{\sim}6$. This behavior of the adsorption of $Ni^{2+}$ according to the solution pH was well agreed with the electrokinetic characteristics of waste pulp in solution. The amount of coexisting solute was observed to reversely affect on the $Ni^{2+}$ adsorption onto waste pulp under the experimental conditions. With regard to the pre-treatment of adsorbent with NaOH, the adsorbability of $Ni^{2+}$ was increased with the concentration of NaOH to a certain extent. However, it was found to decrease contrarily when the concentration of NaOH became too high.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.885-893
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• 2014

This research reports the enhanced Electrokinetic (EK) with $H_2O_2$ and sodium dodecyl surfate (SDS), which are commonly used in Fenton oxidation and soil flushing method, in order to remediate soil contaminated with heavy metals and Total Petroleum Hydrocarbons (TPH) simultaneously. In addition, influences of property of soil and concentration of chemical solution were investigated through experiments of different types of soils and varying concentration of chemical reagents. The results indicated, in the experiments using artificially contaminated soil, the highest removal efficiency of heavy metals using 10% $H_2O_2$ and 20mM SDS as electrolytes. However, in the experiments using Yong-San soils (study area), remediation efficiency of heavy metals was decreased because high acid buffering capacity. Through experiment of 20% $H_2O_2$ and 40mM SDS, increased electric current influences the remediation of heavy metals due to decrease in the soil pH. In the experiments of Yong-San soils, the remediation efficiency of TPH was decreased compared with artificially spiked soils because high acid buffering capacity and organic carbon contents. Furthermore, the scavenger effect of SDS influenced TPH oxidation efficiency under the conditions of injected 40mM SDS in the soils. Therefore, the property of soil and concentration of chemical reagents cause the electroosmotic flow, soil pH, remediation efficiency of heavy metals and TPH.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.18-25
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• 2005

Characteristics of phenanthrene removal in an electrokinetic (EK)-Fenton process were investigated in a viewpoint of concentration and ionic strength of electrolytes. When three kinds of electrolytes (NaCl, $KH_2PO_4,\;and\;MgSO_4$) were used, the increase in electrolyte concentration caused the decrease of electrical potential gradient. The increase of electrical conductivity was due to the increase of ionic concentration in soil. The decrease of accumulated electroosmotic flow (EOF) with increase in electrolyte concentration was due to the decrease of zeta potential. The removal efficiency was in proportion to accumulated EOF which depended on ionic strength. Total energy expenditure without electrolyte was 10-30 times higher than its with 0.5 M electrolyte. The lower removal efficiency was caused by the lower energy expenditure with 0.5 M one. An effective EK-Fenton process was determined from considering the removal efficiency and the energy expenditure, simultaneously.

• Membrane Journal
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• v.13 no.1
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• pp.37-46
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• 2003

The electrokinetic effect can be found in cases of the fluid flowing across the charged membrane micropores. The externally applied body force originated from the electrostatic interaction between the nonlinear Poisson-Boltzmann field and the flow-induced electrical field is taken into the equation of motion. The electrostatic potential profile is computed a priori by applying the finite difference scheme, and an analytical solution to the Navier-Stokes equation of motion for slit-like pore is obtained via the Green's function. An explicit analytical expression for the flow-induced streaming potential is derived as functions of relevant physicochemical parameters. The influences of the electric double layer, the surface potential of the wall, and the charge condition of the pore wall upon the velocity profile as well as the streaming potential are examined. With increasing of either the electric double layer thickness or the surface potential, the average fluid velocity is entirely reduced, while the streaming potential increases.

• KSBB Journal
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• v.21 no.3
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• pp.175-180
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• 2006

In this study, it could be found that the microbial movement in soil under electric field mainly occurred by electrophoresis and electroosmosis. The contribution of electrophoresis on the microbial mobility and flux was generally higher than that of electroosmosis. In the electrokinetic(EK) bioremediation of a pentadecane-contaminated soil, the microbial population increased simultaneously at anode and cathode regions of the soil specimen because both electrophoresis and electroosmosis affected on the microbial movement. After initial operation, the microbial population was high in order of anode, middle, and cathode regions due to their negatively-charged surface and oxygen generation at anode. However, the uniform contaminant removal was achieved by the microbial movement with two-directionality.

• Journal of the Korean Ceramic Society
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• v.32 no.2
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• pp.217-226
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• 1995

Alumina powders were dispersed using crosslinkable organic molecules by electrosteric stabilization and then consolidated by crosslinking of organic molecules. The effect of processing variables such as the physicochemical properties of both solvent media and organic molecules, the proportions of mixed organic media, etc. were studied. FT-IR was used todeduce the mechanism of organic molecules adsorption on the alumina particle surfaces. The adsorption characteristics and the electrokinetic behavior of alumina suspensions were correlated with the stability of particle in alumina suspension using rheological measurements. The green body of alumina consolidated by the chemical crosslinking of the adsorbed organic molecules after the alumina suspension had been stabilized was tough enough for green machining and the sintered alumina fabricated by this proposed process also showed a high bending strength and a homogeneous microstructure.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1230-1236
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• 2012

To verify that the electrokinetic remediation is effective for decreasing salinity of fields of the plastic-film house, field tests for physical property, chemical property, and crop productivity of soils have been conducted. The abridged result of those tests is as follows. In the EK treatment, the electrokinetic remediation has been treated at the constant voltage (about 0.8 V $cm^{-1}$) for fields of the farm household. At this time, an alternating current (AC) 220 V of the farm household was transformed a direct current. The HSCI (High Silicon Cast Iron) that the length of the stick for a cation is 20cm, and the Fe Plate for an anion have been spread out on the ground. As the PVC pipe that is 10 cm in diameter was laid in the bottom of soils, cations descend on the cathode were discharged together. For soil physical properties according to the EK treatment, the destruction effect of soil aggregate was large, and the infiltration rate of water was increased. However, variations of bulk density and porosity were not considerable. Meanwhile, in chemical properties of soils, principal ions of such as EC, $NO_3{^-}$-N, $K^+$, and $Na^+$ were better rapidly reduced in the EK treated control plot than in the untreated control plot. And properties such as pH, $P_2O_5$ and $Ca^{2+}$ had a small impact on the EK. For cropping season of crop cultivation according to the EK treatment, decreasing rates of chemical properties of soils were as follows; $NO_3{^-}$-N 78.3% > $K^+$ 72.3% > EC 71.6% $$\geq_-$$ $Na^+$ 71.5% > $Mg^{2+}$ 36.8%. As results of comparing the experimental plot that EK was treated before crop cultivation with it that EK was treated during crop cultivation, the decreasing effect of chemical properties was higher in the case that EK was treated during crop cultivation. After the EK treatment, treatment effects were distinct for $NO_3{^-}$-N and EC that a decrease of nutrients is clear. However, because the lasting effect of decreasing salinity were not distinct for the single EK treatment, fertilization for soil testing was desirable carrying on testing for chemical properties of soils after EK treatments more than two times. In the growth of cabbages according to the EK treatment, the rate of yield increase was 225.5% for the primary treatment, 181.0% for the secondary treatment, and 124.2% for third treatment compared with the untreated control plot. The yield was increased by a factor of 130.0% for the hot pepper at the primary treatment (Apr. 2011), 248.1% for the lettuce at the secondary treatment (Nov.2011), and 125.4% for the young radish at the third treatment (Jul. 2012). In conclusion, the effect of yield increase was accepted officially for all announced crops.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.1 s.109
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• pp.1-9
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• 2005

Many factors which affect the adsorption of cationic polymers on fibers and fines have been investigated by many researchers that include contact time, pH, collision frequency, properties of cationic polymers and adsorbent, etc. But the effect of white water quality on the adsorption of cationic polymer have not been examined throughly. In this study, the adsorption of cationic PAM was analyzed as a function of white water quality. The adsorption of the cationic PAM was analyzed by two analysis methods, Kjeldahl nitrogen content measurement and electrokinetic measurements. When the distilled water was used, adsorbed amount of C-PAM and zeta-potential of fibers increased as a function of the addition of C-PAM. When closure level increased, nitrogen content of fibers increased indicating that the cationic PAM was adsorbed. Zeta-potential of fibers, however, showed no significant change with the increased addition of C-PAM. This showed that adsorption of C-PAM was not reflected by zeta-potential of fibers due to the deteriorated efficiency of C-PAM by the anionic contaminants in white water.