• 농업과학연구
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• 제10권2호
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• pp.345-353
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• 1983

수용액에 존재하는 중금속이온중의 Hg(II)을 정량적으로 분리 회수하기 위하여 DBHQ(5. 7-dibromo-8-hydroxyquinoline)을 Open-pore polyurethane foam (OPP foam)에 침윤시켜 수지의 응용성을 연구하였다. Hg(II)의 흡착은 DBHQ와 1:2 몰비의 착물형성이 이루어지며 Hg(II)의 흡착과 분리는 Batch법으로 실험하여 최적조건을 결정하였다. 가장 양호한 흡착은 DBHQ의 등전점인 pH5.0 부근에서 그리고 분리하는데는 4M-HCl, 50% 아세톤 용매를 사용하였을 경우가 비교적 정량적인 흡착과 분리가 이루어지는 조건이었으며 이와같은 결과를 기초로 DBHQ-OPP foam에 대한 Hg(II)의 흡착 및 분리에 대한 반응메카니즘을 제안했다.

• Environmental Engineering Research
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• 제22권1호
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• pp.95-107
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• 2017

Adsorption equilibrium and kinetic behavior of two toxic heavy metals hexavalent chromium [Cr(VI)] and mercury [Hg(II)] on mustard oil cake (MOC) was studied. Isotherm of total chromium was of concave type (S1 type) suggesting cooperative adsorption. Total chromium adsorption followed BET isotherm model. Isotherm of Hg(II) was of L3 type with monolayer followed by multilayer formation due to blockage of pores of MOC at lower concentration of Hg(II). Combined BET-Langmuir and BET-Freundlich models were appropriate to predict Hg(II) adsorption data on MOC. Boyd's model confirmed that external mass transfer was rate limiting step for both total chromium and Hg(II) adsorptions with average diffusivity of $1.09{\times}10^{-16}$ and $0.97m^2/sec$, respectively. Desorption was more than 60% with Hg(II), but poor with chromium. The optimum pH for adsorptions of total chromium and Hg(II) were 2-3 and 5, respectively. At strong acidic pH, Cr(VI) was adsorbed by ion exchange mechanism and after adsorption reduced to Cr(III) and remained on MOC surface. Hg(II) removal was achieved by complexation of $HgCl_2$ with deprotonated amine ($-NH_2$) and carboxyl (COO-) groups of MOC.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1877-1880
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• 2004

The simple and convenient determination of trace Hg(II) with its 2-mercaptobenzothiazole (MBT) complex in cetyltrimethylammonium bromide (CTAB) media has been studied. The UV-visible spectrum of Hg(II)-MBT complex in CTAB media had a good sensitivity and reproducibility. The Hg(II)-MBT complex in CTAB solution was very stable at pH 10.0 and could be quantitatively complexed if MBT were added to the sample solution more than 10 equivalent of Hg(II). The optimum concentration of CTAB was 0.001%. The calibration curve of Hg(II)-MBT complex with good linearity ($R^2$ = 0.9985) was obtained at the concentration range between $1.0{\times}10^-7$ and $1.0{\times}10^-5$ M in 0.001% CTAB media. The detection limit was $3.1{\times}10^-8$ M (6.2 ng m$L^{-1}$). Hg(II) in the synthetic samples and in the wastewater of the university's wastewater tank and the industrial wastewater tank could also be determined. Based on the experimental results, this proposed technique could be applied to the simple and convenient determination of trace Hg(II) in real samples.

• 대한화학회지
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• 제35권4호
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• pp.355-361
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• 1991

수용액 시료 중 흔적량 수은[Hg(II)]을 공침-부선기술에 의하여 분리-농축하는 방법에 관하여 연구하였다. 물시료 1000ml에 0.1M Ce$^{3+}$ 용액 3.0 ml를 가하고, 1.0M NaOH 용액으로 pH를 11.0으로 되게 조절하여 Hg(II)를 Ce(OH)$_3$와 함께 공침시켰다. 0.1${\%}$ sodium oleate 용액 2.0 ml를 가하여 만든 소수성 침전을 질소기체로 bubbling하여 용액 표면으로 띄웠다. 뜬 침전을 감압 플라스크에 모으고 2.0M HNO$_3$ 5.0 ml 로 녹였다. 탈이온수로 용액을 묽혀 25.00 ml로 정확히 만들었다. Hg(II)의 함량을 냉증기-원자흡수 분광법으로 정량하였다. 정량과정에서 Ag$^+$, Br$^-$, I$^- $ 등의 간섭은 관찰되지 않았다. 고려대학교 서창캠퍼스의 폐수에서 Hg(II)의 분석결과는 1.98 ng/ml 이었고, 이 값에 대한 상대표준편차는 3.6${\%}$이었다. 또 이 폐수에 1.0과 2.0ng/ml의 Hg(II)를 첨가하여 분석한 회수율은 각각 95와 91${\%}$이었다. 이런 결과로부터 본 분석법이 물시료 중 흔적량 Hg(II)의 정량에 꽤 정확하고 재현성이 있음을 확인할 수 있었다.

• 대한화학회지
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• 제51권4호
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• pp.324-330
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• 2007

수은(II) 이온 센서로 이온투과 담체로서 bis(benzoylacetone) propylenediimine (H2(BA)2PD)을 근간으로 하는 새로운 이온 선택 PVC 막 전극이 개발하였다. 이 전극은 좋은 감응 특성을 보였고, 29.8±0.75 mV/10의 Nernstian 기울기로 부터 1.0×10-6-1.0×10-1 M 수은(II) 이온 농도 범위에서 선형 Emf vs. log[Hg2+]를 보였다. pH 2.5-11.5에서 검출한계는 2.2×10-7 M Hg(II)를 보였다. 다수의 전위 간섭이온에의 수은(II)이온 대한 선택 농도에 대해 역시 연구되었다. 이 센서는 다른 전하와 함께 많은 수의 양이온에 있어 수은(II)이온에 대해 고선택성을 보였다. 이 센 서는 60초 안에 빠는 감응을 보이며 화학적으로 불활성인 것을 알아 내었고 3개월 동안 좋은 재현성을 보였다(S = 0.27 mV). 이 전극은 실제 시료에서 수은(II)이온 의 분석에 대해 서도 만족할 만한 결과를 얻었다.

• 분석과학
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• 제8권3호
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• pp.259-264
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• 1995

수용액서 poly-NTOE(1, 12-diaza-3, 4:9, 10-dibenzo-5, 8-dioxacyclopentadeca-1, 12-ylene-2, 7-dihydroxyoctamethylene)를 흡착시킨 실리카겔을 고정상으로 하는 액체 크로마토그래피를 이용하여 혼합 금속이온용액으로부터 전이금속 및 후전이금속이온들의 분리효율을 결정하였다. pcly-NTOE와 금속이온들간의 결합상수 및 분리인자들의 순위는 전이금속이온의 경우 Co(II)Zn(II)였으며, 후전이금속이온들의 경우 Cd(II)

• 한국환경보건학회지
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• 제14권2호
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• pp.65-71
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• 1988

In this study, the method of adsorption by activated carbon in the removal of Hg(II) ion in waste water was treated. The influence of kinds of activated carbon and effect of temperature and the influence of coexistent salt on adsorption rates, the influence of pH in the adsorption, equilibrium and adsorption of mercury from activated carbon were investigated. From the adsorption on activated carbon of mercury(II) ion in the presence of cyanide or thiocyanate ion was found that mercury(II) was easily adsorved onto the activated carbon in the form of complex artion such as Hg(CN)$_4^{2-}$, Hg(SCN)$_4^{2-}$ respectively. ZnCl$_2$ activation method had a higher adsorptive ability than steam activation method in adsorption of Hg on activated carbon. Activated carbon adsorbed iodide ion is very effective on adsorption of Hg.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.519-523
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• 2011

We studied the detection of the Hg(II) concentration in an aqueous solution using rhodamine dyes on citrate-reduced Au nanoparticles (NPs). The quenching effect from Au NPs was found to decrease as the Hg(II) concentration increased under our experimental conditions. As the fluorescence signals intensified, the surface-enhanced Raman scattering (SERS) intensities reduced on the contrary due to less rhodamine dyes on Au NPs as the Hg(II) concentration increased. The rhodamine 6G (Rh6G) and rhodamine 123 (Rh123) dyes were examined via fluorescence and SERS measurements depending on Hg(II) concentrations. Fast and easy fluorescence detection of an Hg (II) concentration as low as a few ppm could be achieved by naked eye using citrate-reduced Au NPs.

• Toxicological Research
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• 제24권1호
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• pp.23-28
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• 2008

Voltammetric analysis of mercury ions was developed using paste electrodes (PEs) with DNA and carbon nanotube mixed electrodes. The optimized analytical results of the cyclic voltammetry (CV) of the $1{\sim}14ng\;L^{-1}Hg(II)$ concentration and the square wave (SW) stripping voltammetry of the $1{\sim}12ng\;L^{-1}Hg(II)$ working range within an accumulation time of 400 seconds were obtained in 0.1 M $NH_4H_2PO_4$ electrolyte solutions of pH 4.0. For the relative standard deviations of the $1ng\;L^{-1}Hg(II)$, which were observed at 0.078% (n = 15) at the optimum conditions, the low detection limit (S/N) was pegged at $0.2ng\;L^{-1}(7.37{\times}10^{-13}M)$ for Hg(II). The results can be applied to assays in biological fish kidneys and wastewater samples.

• 공업화학
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• 제34권5호
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• pp.556-565
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• 2023

Fast industrial and agricultural expansion result in the production of heavy metal ions (HMIs). These are exceedingly hazardous to both humans and the environment, and the necessity to eliminate them from aqueous systems prompts the development of novel materials. In the present study, a UIO-66 (COOH)₂ metal-organic framework (MOF) containing free carboxylic acid groups was post-synthetically modified with L-glutamic acid via the solid-solid reaction route. Pristine and glutamic acid-treated MOF materials were characterized in detail using several physicochemical techniques. Single-ion batch adsorption studies of Pb(II) and Hg(II) ions were carried out using pristine as well as amino acid-modified MOFs. We further examined parameters that influence removal efficiency, such as the initial concentration and contact time. The bare MOF had a higher ion adsorption capacity for Pb(II) (261.87 mg/g) than for Hg(II) ions (10.54 mg/g) at an initial concentration of 150 ppm. In contrast, an increased Hg(II) ion adsorption capacity was observed for the glutamic acid-modified MOF (80.6 mg/g) as compared to the bare MOF. The Hg(II) ion adsorption capacity increased by almost 87% after modification with glutamic acid. Fitting results of isotherm and kinetic data models indicated that the adsorption of Pb(II) on both pristine and glutamic acid-modified MOFs was due to surface complexation of Pb(II) ions with available -COOH groups (pyromellitic acid). Adsorption of Hg(II) on the glutamic acid-modified MOF was attributed to chelation, in which glutamic acid grafted onto the surface of the MOF formed chelates with Hg(II) ions.