• Environmental Engineering Research
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• 제10권5호
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• pp.205-212
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• 2005

The study was conducted to investigate the removal of heavy metals by using Hydroxyapatite(HAp) made from waste oyster shells and wastewater with high concentration of phosphorus. The maximum calcium concentration for the production of HAp in this study was released up to 361 mg/L at pH of 3 by elution experiments. When the pH was at adjusted 6, the maximum calcium released concentration was 41 mg/L. During the elution experiment, most of the calcium was released within 60 minutes. This reaction occurred at both pH levels of 3 and 6. The result of the XRD analysis for the HAp product used in this study shows the main constituent was HAp, as well as OCP. The pH was 8.6. As the temperature increased, the main constituent did not vary, however its structure was crystallized. When the pH was maintained at 3, the removal efficiency decreased as the heavy metal concentration increased. The order of removal efficiency was as follows: $Fe^{2+}$(92%), $Pb^{2+}$(92%) > $Cu^{2+}$(20%) > $Cd^{2+}$(0%). Most of these products were dissolved and did not produce sludge in the course of heavy metals removal. As the heavy metal concentration increased at pH of 6, the removal efficiency increased. The removal efficiencies in all heavy metals were over 80%. From the analysis of the sludge after reaction with heavy metals, the HAp was detected and the OCP peak was not observed. Moreover, lead ion was observed at the peaks of lead-Apatite and lead oxidant. In the case of cadmium, copper and iron ions, hydroxide forms of each ion were also detected.

• 산업기술연구
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• 제27권A호
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• pp.19-24
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• 2007

This research was done for possible treatment of impermeable surfaces rainwater runoff containing heavy metal ions by manganese oxide coated on polypropylene support. Manganese oxide was coated by Birnessite Coating Methods(BCM)and the coating analyzed by SEM and FT-IR techniques. The efficiency of heavy metal ions adsorption was also assessed via both batch and column tests. Adsorption efficiencies of Cd, Zn, Cu, and Pb were 99.4%, 98.9%, 96.7%, and over 95.7%, respectively. The adsorption progress pattern reveals quite fast adsorption at initial periods of treatment and change to slower rates at later times.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.103-111
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• 2015

Soil washing with ethylenediaminetetraacetic acid (EDTA) is highly effective in the remediation of soils contaminated with heavy metals. The EDTA recycling process is a requisite for reducing the operating cost. The applicability of Na₂S addition on the precipitation of heavy metals from the spent soil washing solution and thereby recycling of EDTA was investigated. Addition of Na₂S into the single metal-EDTA and the mixed metal-EDTA solutions ([Na₂S]/[metal-EDTA] ratio = 30, reaction time = 30 min and pH = 7~9) was highly effective in the separation of Cu and Pb from metal-EDTA complexes, but not for Ni. The Zn removal efficiency varied with pH and slightly increased upto 40% as the reaction time increased from 0 to 240 min which was longer than those for Cu and Pb. Ca(OH)₂ was subsequently added to induce further precipitation of Zn and Ni and to reduce the Na₂S dose. At the [Na₂S]/[metal-EDTA] ratio of 10, the removal efficiencies of all heavy metals excluding Ni were above 98% with the dose of Ca(OH)₂ at 0.002, 0.006 and 0.008 g into 100 mL of Cu-, Pb- and Zn-EDTA solutions, respectively. However, Ca(OH)₂ addition was not effective for Ni-EDTA solution. A further research is needed to improve metal removal efficiency and subsequent EDTA recycling for the real application in field-contaminated soils.

• 한국물환경학회지
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• 제26권4호
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• pp.687-690
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• 2010

The objective of this study is to investigate the effect of aldehyde compounds and ploysulfide as accelerating agents on removal of heavy metals and CN in plating wastewater. As a results of the experiments, the removal efficiency of cyanide using the formaldehyde type of aldehydes was the highest at pH 9. Next types were sodium formaldehyde bisulfite addut> paraldehyde> paraformaldehyde. Also, optimum pH and dosage for treating the residual heavy metals by using polysulfide were pH 9 and 30 mg/L, respectively. The removal efficiencies of cyanide, chromium, zinc and copper were above 96.7% at optimum condition.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.103-104
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• 2005

• 광물과 암석
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• 제35권3호
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• pp.387-396
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• 2022

본 연구에서는 꼬막(cockle), 전복(abalone), 가리비(scallop) 패각을 이용하여 중금속 제거효율 평가를 수행하였다. 꼬막, 전복, 가리비의 주 구성광물은 각각 아라고나이트, 아라고나이트와 방해석, 방해석으로 구성되어 있다. 각 패각들의 비표면적은 2.7241 m²/g에서 4.5481 m²/g까지 다양하며 가리비 > 전복 > 꼬막이다. 반응 후 중금속 분석 결과 As는 패각에 의한 흡착이나 pH 상승에 의한 침전 제거 효과가 나타나지 않았다. 납은 반응 초기에 모든 패각 시료에서 모두 제거되었다. 카드뮴과 아연은 매질에 따라 약간의 차이가 있지만 제거 효율은 가리비 > 전복 > 꼬막 순으로 나타났다. 중금속 제거 효율은 가열 시료가 원시료 비해 약간 높으며, 비표면적이 클수록 높은 경향이 있다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권5호
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• pp.128-134
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• 2017

This work presents the adsorption capability of green tea and ginseng leaves to adsorb heavy metals such as Cd(II), Cu(II), and Pb(II) in aqueous solution. FT-IR analysis indicates the presence of oxygen containing functional groups (carboxyl groups) in two kinds of leaves. High pH condition was favorable to the adsorption of heavy metal ions due to the enhanced electrostatic attraction and the precipitation reaction of metal ions. The adsorption of Cd(II), Cu(II), and Pb(II) reached equilibrium within 10 min, achieving high removal efficiencies of 80.3-97.5%. The adsorption kinetics data of heavy metal ions were fitted well with the pseudo-second-order kinetic model. The maximum adsorption amounts of Cd(II), Cu(II), and Pb(II) ions were 8, 3.5, and 15 mg/g, respectively, in the initial concentration range from 0.15 to 0.75 mM. Based on the fitting data obtained from isotherm models, heavy metal adsorption by green tea and ginseng leaves could occur via multi-layer sorption.

• 한국지반환경공학회 논문집
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• 제15권12호
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• pp.15-24
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• 2014

천연제올라이트와 불가사리를 목분과 함께 혼합 소성한 펠렛형 Zeolite-StarFish 세라믹(ZSF 세라믹)을 이용하여 산성광산배수 내 중금속의 제거특성 및 영향인자를 파악하고자 하였다. ZSF 세라믹에 의한 중금속의 제거반응은 초기 3시간까지 빠른 속도로 진행되었으며 높은 알칼리 상태를 나타내었다. 중금속 제거를 위한 ZSF 세라믹의 최적 소성온도는 $800{\sim}1,000^{\circ}C$로 파악되었으며 소성시간에 따른 중금속 제거효율의 변화는 거의 나타나지 않았다. ZSF 세라믹의 최적 투여농도는 1.0~1.2 %임을 알 수 있었고, 1.0 % 이상의 ZSF 세라믹의 투여농도 조건에서는 Pb 85.5 %를 제외한 Al, As, Cd, Cu, Fe, Mn, Zn 대부분의 중금속이 95 % 이상의 높은 제거효율을 나타내었다. 목분의 배합비가 증가할수록 중금속 제거효율은 증가하였으며 목분의 적정 배합비는 10 %로 파악되었다. 회분식 실험을 통해 불가사리 소재의 ZSF 세라믹은 산성광산배수 내 중금속을 효과적으로 제거할 수 있는 처리제임을 알 수 있었으며, 특히 목분을 첨가한 다공성 ZSF 세라믹을 통해서는 산성광산배수 내 중금속의 제거효율을 더욱 향상시킬 수 있었다.

• 한국미생물·생명공학회지
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• 제36권2호
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• pp.165-172
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• 2008

본 연구에서는 분리균주 LH2를 이용하여 각각의 중금속 (Cr, Cu, Ni, Pb, Zn)에 대한 최적성장조건을 도출하였으며, pH, 온도 및 중금속 농도 변화에 따른 중금속 제거효율을 관찰하였다. 분리균주는 18S rDNA 분석에 의거하여 종 유사성이 100%로서 Exophiala sp.로 동정되었다. 분리균주의 경우 $25^{\circ}C$, pH 7인 진탕배양 조건에서 가장 높은 제거효율을 보였다. 첨가되는 중금속의 농도가 200 ppm이하일 경우 중 금속의 비제거속도를 구한 결과 pH 7인 조건에서 중금속의 종류와 무관하게 10 ppm에서 200 ppm으로 중금속의 농도가 증가함에 따라 0.01에서 4.43 mg-metal $L^{-1}{\cdot}d^{-1}{\cdot}mg^{-1}{\cdot}DCW^{-1}$으로 증가하였다. pH 7로 설정된 배양액에 약 200ppm의 중금속이 첨가될 경우 중금속의 제거효율은 Cr, Cu, Ni, Pb, 및 Zn 이 각각 99.28%, 97.67%, 91.94%, 99.77%, 99.61%로 관찰되었다.

• 대한환경공학회지
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• 제31권6호
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• pp.454-459
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• 2009

본 연구에서는 다목적으로 사용가능하고 환경친화적인 potassium ferrate를 이용하여 강물의 humic acid와 중금속(Cu, Mn, Zn)을 동시에 제거하고자 하였다. 0.03${\sim}$0.7 mM (as Fe) ferrate를 이용해서 0.1 mM 중금속을 처리한 결과, Cu에 대해 28${\sim}$99%, Mn에 대해 22${\sim}$73%, Zn에 대해18${\sim}$100%의 제거효율을 얻었다. Humic acid와 중금속의 혼합용액에 0.03${\sim}$0.7 mM (as Fe) ferrate를 주입하여 각 물질을 다음과 같이 동시에 효과적으로 제거할 수 있었다: 49${\sim}$81% (humic acid), 93${\sim}$100% (Cu), 22${\sim}$86% (Mn), 20${\sim}$100% (Zn). 혼합용액에서 humic acid와 각 중금속 제거효율이 단일 중금속과 humic acid 용액에서의 결과보다 높은데, 이는 혼합용액에 ferrate를 주입하기 전, humic acid의 음이온 작용기와 중금속 양이온의 반응에 의해 착화합물이 형성되어 일부가 제거되었기 때문이다.