• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.606-611
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• 2016

In this work, the treatment of heavy metals and phenol in the contaminated soil was investigated by applying direct current (DC) and pulse voltage. When the DC was used, the removal efficiencies for Cu, Zn, As, and Pb were 73, 88, 10, and 10%, respectively, and more than 95% for phenol was removed. Furthermore, when a pulse voltage was employed the removal efficiencies for Cu, Zn, As, and Pb were 88, 92, 40, and 40%, respectively, and 87% of phenol was removed. The results indicate that the application of a pulse voltage for the treatment of contaminated soil reduced electro-osmosis, but increased the rate of electric current movement of heavy metals. In addition, the removal efficiencies for As and Pb have been improved due to the enhanced adsorption capacity of clay components in the soil. Therefore, these experimental results could be effectively applied in remediation technology for the treatment of various heavy metals and phenol.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.529-539
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• 2019

In this study, heavy metal removal and precipitation characteristics with pH change were studied for artificial acid mine drainage. Artificial acid mine drainage was prepared using sulfates of iron, aluminum, copper, zinc, manganese which contained in acid mine drainage from abandoned mines. The single and mixed five heavy metal samples of Fe, Al, Cu, Zn, and Mn were prepared at initial concentrations of 30 and 70 mg/L. Fe and Al were mostly removed at pH 4.0 and 5.0, respectively, and other heavy metals gradually decreased with increasing pH. Concentration changes with increasing pH show generally similar trend for single and mixed heavy metal samples. The effect of removing heavy metals from aqueous solutions is not related to the initial concentration and depends on the pH change. XRD were used for mineral identification of precipitates and crystallinity of the mineral tended to increase with increasing pH. The precipitates that produced by decreasing the concentration of heavy metals in the aqueous solution composed of Fe-goethite(FeOOH), Al-basaluminite(Al₄(SO₄)(OH)₁₀·4H₂O), Cu-connellite(Cu₁₉(OH)₃₂(SO₄)Cl₄·3H₂O) and tenorite(CuO), Zn-zincite(ZnO), and Mn-hausmannite(Mn₃O₄).

• Analytical Science and Technology
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• v.13 no.1
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• pp.96-100
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• 2000

The adsorption of heavy-elements to zeolite has been investigated at various adsorptional condition for purification of waste water. Four heavy elements, Cd, Cr, Cu and Pb, were examined, because they are concerned to the major heavy-element contamination. The adsorption efficiencies are measured at the different conditions such as adsorption times and pHs. The practical adsorption was achived and reaches to maximum within 30 minute by using of 2-g zeolite for 50 mL of heavy-element solution. The overall adsorption efficiencies for Cr and Cu are high and become better at low pH. Cd and Pb have 95% of adsorption ratio and this is lower than other two elements. Cadmium shows an abnormally low adsorption at low pH.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.87-101
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• 1999

This study has been carried out to examine the feasibility of washing technique for reducing the heavy metal contamination level of tailing wastes and agricultural soil surrounding abandoned metal mines. Some organic acids with low molecular weight were used as washing solution. Initial contamination levels of copper and lead for some soil samples were found to exceed the standard levels of countermeasure and concern, and those of cadmium to approach the standard level of countermeasure. Experimental results using sequential extraction method revealed that more than half of copper and lead existing in tailing wastes are adsorbed forms available for plants. There are some proportional relationships between metal concentrations determined by using 0.1N HCI solution and those determined by sequential extractions. Citric acid was turned out to be superior to oxalic acid and acetic acid with low molecular weight in washing above three metals. When citric acid is used for washing heavy metals from soil, it is desirable to operate at pH less than 5.5 for better washing effect. Metal removal effect by citric acid solution has been proved to depend upon solution concentration and the mass ratio of solution to soil. Addition of SDS(Sodium Dodecyl Sulfate) to citric acid improved the washing effect of cadmium among three metal most significantly. while copper removal did not change. Washing technique using citric acid for removal of heavy metals from agricultural soil or tailing wastes is recognized to be an effective remediation method.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.5
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• pp.535-541
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• 2005

Peat humin(p-Humin) extracted from Canadian Sphagnum peat moss was packed in a column and removal of heavy metal ions such as Cd, Cu and Pb from aqueous solution under flow conditions was studied. The metal ions were removed not only from single-element solutions but also from a multi-metal solution. Column kinetics for metal removal were described by the Thomas model. For single-component metal solutions, the maximum adsorption capacities of the p-Humin for Pb, Cu and Cd were 138.8, 44.66 and 41.61 mg/g, respectively. The results of multi-component competitive adsorption showed that adsorption affinity was in the order of Pb $\gg$ Cu > Cd. The adsorbed metal ions were easily deserted from the p-Humin with 0.05 N $HNO_3$ solution. It is apparent that 95% of the heavy metal ions were recovered from the saturated column. This investigation provides possibility to clean up heavy-metal contaminated waste waters by using the natural biomass, p-Humin as an environmentally friendly and cost-effective new biosorbents.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.74-76
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• 2001

물상추에 의한 Pb 제거효율은 96시간 동안 0.5 mg/L 일 때 71.4%, 1mg/L일 때 65.6%, 1.5 mg/L일 때 81.2%로 나타났으며, 0.5 mg/L 일 때 24시간만에 24.6%로 가장 높은 제거효율을 나타냈다. 또한 농도가 높아질수록 높은 제거효율을 나타냈다. $Cr^{6+}$ 의 제거효율은 높은 농도에서 시간이 지날수록 제거효율이 높아졌다각 수조별 pH 변화는 전반적으로 높아지는 경향을 보였고 Pb의 경우는 1.5 mg/L에서 96시간 동안 6.7에서 7.73으로 가장 큰 변화를 보였다. 수온을 23 ～ 26$^{\circ}C$로 유지하면서 물상추의 비성장율을 살펴본 결과 Pb의 경우 1.5mg/L에서 24시간만에 0.046g $day^{-1}$에서 96시간 후에는 1.5 mg/L에서 0.114 g $day^{-1}$로 가장 높은 성장을 보였으며 $Cr^{6+}$ 의 경우도 1 mg/L에서 24시간 후에 0.0l2g $day^{-1}$에서 96시간 후에는 0.5 mg/L에서 0.07g $day^{-1}$로 가장 높은 성장률을 보였다. 중금속 수조의 $NH_3-N$, $NO_3$-N, T-P 제거효율을 보면 $NH_3-N$는 전체적으로 50%이상의 높은 제거효율을 보여 영양원으로서의 흡수가능성을 보였고 $NO_3$-N와 T-P의 경우는 전체적으로 낮은 제거효율을 보였다.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.541-548
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• 2009

Iron coated media (activated carbon, sand and starfish) were prepared at pH 4 and applied for the treatment of landfill leachate containing organic compounds and soluble metal ions such as $Zn^{2+},\;Cu^{2+},\;Mn^{2+}$ in batch and column experiment. The amount of iron coated in media was analyzed with EPA 3050B method. The removal efficiency of metal ions and phenol was compared with iron coated media. The amount of iron coated in Fe-AC and ICS(iron coated sand) were 1,612 mg/kg and 1,609 mg/kg, respectively, while it was higher with 1,768 mg/kg in ICSF(iron coated starfish). The result of batch study represent the highest removal efficiency in the treatment of wastewater using iron coated starfish. In column study, the removal efficiency of phenol and metal ions was higher in multi-layered system of ICS, Fe-AC and ICSF compared to single layered system. Breakthrough time in the effluent was relatively enhanced for $Cu^{2+}$ and $Zn^{2+}$ in multi-layered system while the removal efficiency of $Mn^{2+}$ were not varied much. Therefore, multi-layered system was identified as the better system for the treatment of wastewater containing of metal ions and organic compound.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.327-332
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• 2019

Today's scientists try to remove heavy metals with many new technologies such as phytoremediation. One of the best cutting edge technologies is developing transgenic plants to remove certain heavy metal in soil. I constructed the transformation vector expressing T. goesingense Metal Transport Protein1 gene and TgMTP1: GFP genes. The transgenic plants were selected and confirmed the transformed genes into Arabidopsis thaliana genome. Expression was confirmed in several parts in Arabidopsis cells, tissues and organs. When TgMTP1 overexpressing Arabidopsis thaliana were subjected, transgenic plants showed higher heavy metal tolerance than non-transgenic. For further study I selected the transgenic plant lines with enhanced tolerance against four different heavy metals; Zn, Ni, Co, Cd. The accumulation of these metals in these plants was further analyzed. The TgMTP1 overexpressing Arabidopsis thaliana plant of selected lines are resistant against heavy metals. This plant is characterized by the expression of the MTP1 gene accumulating heavy metal in the vacuole and being simultaneously expressed on the plasma membrane. In conclusion, these plants may be used in plant purification applications, and as a plant with increased tolerance.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.31-44
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• 1998

The geochemical experiments were carried out to investigate a removal effect of heavy metals in abdndoned metallic mine wastes, and to conceive a treatment techniques of them. In order to prevent contamination, experiment appature was made of acrylic acid resin and polyethylene which resist to acid and alkali. Experiment models are devided into four groups based on the system environments, distribution patterns and a kind of filling materials. The first group is background model(model I ) which is filled with waste only and opened to air. The second one is four layer group which is subdivided into two models, opened and closed systems, and the third mix group which is subdivided into three models based on mixing ratio of filling materials and system environment like a layered group. The forth is composed of two layer model, lower one composed of waste and upper one limestone chips. Solution drained from Model Ishows a high contents of heavy metals on the all terms of experiments. Among the models, however, the closed mix model V and Ⅶ show the most effective removal of heavy metals liberated from wastes. Models having different mixing ratios of filling materials on closed systems does not affect in heavy metal removal effect. But, the distribution patterns of filling materials affect very much on removal effect of heavy metals. The closed models with same constitution ratios and distribution patterns of filling materials show more and less effective removal to the open models.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.218-222
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• 2000

Wasted${\cdot}$rested mine areas give lots of effect on around-environmental changes after mining development. Leaching water at reclaimed land has been eluted from the solid components through physical, chemical, biological procedures by waters percolated through reclaimed site. The element analysis of waste tungsten ore tailing, leaching water analysis and removal of heavy metal by zeolite were performed to investigate the influent of acid rain on the released contents of H. M. The heavy metal contents in leaching water were determined to be As $1.21\;{\sim}\;1.54\;ppm$, Pb $0.11\;{\sim}\;0.15\;ppm$ and $SO_4\;^{2-}$ was $302\;{\sim}\;378ppm$. As deionized water and simulated acid rain (pH 3,4) were percolated through columns packed tungsten ore tailing, the amount of Mn, Na, Ca which were dissolved by pH4 solution was higher than those by distilled water. However, W and Mo were eluted easily by high pH solution. The change of heavy metal concentration by column experiment packed zeolite was effective a little because heavy metals were adsorved much more by zeolite.