• Journal of Environmental Health Sciences
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• v.14 no.2
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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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• v.15 no.10
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• pp.836-841
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• 1994

The polymer matrix effect on the selectivity, response rate and reproducibility for coextraction type anion-selective optode membranes were investigated with DOA-plasticized PVC, PVC/hydroxylated PVC, PU/hydroxylated PVC and DOS-plasticized CTA matrices. Optode membranes were prepared with TDMACl and ETH2412 dissolved in one of the four solvent polymeric matrices. The PU/hydroxylated PVC and PVC-based membranes have almost the same selectivity coefficients, while the CTA-based membrane is more selective toward lipophilic anions. The membrane with PU/hydroxylated PVC adhered strongly to a glass surface, and showed highly reproducible and relatively rapid response. Very poor adhesion of PVC/hydroxylated PVC and CTA-based membranes limited the usability of those membranes as sensor components. Based on these results, and considering the biocompatibility for clinical samples, the optode made with PU/hydroxylated PVC was applied to determine the thiocyanate ion in human saliva. The results obtained with this simple device were comparable to those with rather complicated ISE methods.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.139-141
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• 1968

The extraction curve of metal ions with Amberite LAl-chloroform has been found to be more steeper than with Amberite LAl-xylene or hexane, and the extraction ratio of Zn (II) in 2M HCl solution is 98%. The extraction ratio of As (III) in 9~11M HCl soln., Sb (III) in 2~4M HCl soln., and Fe (III) in 6~10M HCl soln. are 100%. The separated elements from Bi metal were determined by colorimetry, Zn (III) with dithizone, As (III) with Gutzeit method, Sb (III) with brilliant green and Fe (III) with thiocyanate.

• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.13-20
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• 1991

Ion-selective electrode responsive to the thiocynate ion prepared by using the quaternary ammonium salts as a active material and PVC as a membrane matrix. The effect of chemical structure and composition of active material, and the membrane thickness on the linear response. the detection limit, and Nernstian slope of the electrode studied. Under the above optimum conditions of membrane, the effect of pH and the selectivity coefficients to various interfering anions were compared and investigated. It was concluded that the functions of thiocynate ion-selective electrode(ISE) were closely related to the chemical structure of the quaternary ammonium salts. The linear response, and the detection limit of the electrode potential increased with the increase of the carbon chain length of the alkyl group in the quaternary ammonium salts in the ascending order of Aliquat 336T, TOAT, TDAT, and TDDAT. The optimum membrane thickness was 0.3mm. The electrode characteristics was better with the decrease of the concentration of active material, and the best concentration was 3 weight percent. The membrane potential was independent of the pH variation in the region from pH 2 to 12. The order of the selectivity coefficients is as follows：Cl $O_4$$^{[-10]}$ ＞ $I^{[-10]}$ ＞N $O_3$$^{[-10]}$ ＞B $r^{[-10]}$ ＞ $F^{[-10]}$ ＞C $l^{[-10]}$ ＞O $A_{c}$ $^{[-10]}$ 〓S $O_4$$^{2-}$.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.42-47
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• 1961

A titration of a small amount of iron with standard potassium ferrocyanide using potassium thiocyanate as indicator has been studied. A sample solution containing $0.1{\sim}1.0$ mg. $Fe^{3+}$ in 60 ml. is pipeted into 100 ml. Erlenmyer flask and the pH of the solution is adjusted to $1.5{\sim}3.0$ with 0.1 N or 1 N $HNO_3$ and $NH_4OH.$ To this solution one ml. of 1 M KCNS solution as indicator is added. The solution colored by iron thiocyanate complex is titrated with 1/200 M or 1/400 M standard solution of potassium ferrocyanide from a 5 ml. micro-buret. Near the end point, when the color of sample changes from deep red to green, about 20 ml. of ether is added and shake the flask vigorously. The red color is extracted to the ether layer. To settle the ether layer a few drops of ethanol is added and then standard solution is added dropwise and shake vigorously. The end point is reached when the color of the ether layer disappears owing to the quantitative formation of $Fe_4[Fe(CN)_6]_3.$ In this titration, 0.lmg. of $Fe^{3+}$ can be determined within 1.0% of titration error, provided the following optimum conditions, i.e., pH $1.5{\sim}3.0$, final concentration of KCNS indicator; $0.01{\sim}0.02M$, at room temperature. The titration found to be interfered by the presence of slightly soluble salts, stable complex forming ions and the ions which would be reduced by ferrocyanide or oxidized by ferric ion.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.12-13
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• 1993

십자화과 채소에는 여러종류의 glucosinolate가 존재하며 이들 중 특히 indolw형 glucosinolate는 여러가지 요인에 의해 분해되어 항암효과를 나타내는 물질들을 생성한다고 보고 되고 있다. 이에 다라 우리나라 농가에서 대량 생산되고 있는 십자화과 채소인 배추 및 무에서 항암전구물질인 indole glucosinolate를 포함한 glucosinolate를 분석 및 동정하고 가공처리조건에 따라 항암물질인 indoleacetonitrile과 indolemethanol의 함량을 측정하였다. 1. GC 및 GC-MS를 이용하여 배추, 무의 품종별 ; 이들 씨에서 4-8종류의 glucosinolate를 동정하였다. 2. Thymol에 의한 총 glucosinolate의 함량은 배추 및 무에서는 복돌이 배추와 왕관무가 3.21, 2.0$\nu$mole/g으로 가장 많았고 배추씨, 무씨에서는 각각 6.38, 4.07$\nu$mole/g이었다. 3. 배추 및 무의 저장중 총 glucosinolate함량은 저장 기간이 지남에 따라 점차 감소하는 경향이였다. 4. 열처리 시간에 따른 배추와 무의 indoleacetonitrile함량은 열처리 시간이 지남에 따라 증가하며 40분 열처리시 최대치를 나타내었다. 5. indolemethanol이 생성될때 방출되는 배추, 무, 배추씨 및 무씨의 Thiocyanate ion의 함량은 열처리 시간이 지남에 따라 증가하며 40분 열처리시 최대치를 나타내었으며 자가분해에 따른 함량도 분해시간이 경과함에 따라 증가하며 30분경과시는 최대치를 나타내었고 이는 40분 열처리시보다 많은 함량이였다.함량이였다.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.384-388
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• 2003

The emission and excitation spectra of $cis-[Cr(cyclam)(NCS)_2]NCS$ (cyclam = 1,4,8,11-tetraazacyclotetradecane) taken at 77 K are reported. The infrared and visible spectra at room temperature are also measured. The vibrational intervals due to the electronic ground state are extracted from the far-infrared and emission spectra. The ten pure electronic origins due to spin-allowed and spin-forbidden transitions are assigned by analyzing the absorption and excitation spectra. Using the observed transitions, a ligand field analysis has been performed to determine the bonding properties of the coordinated ligands in the title chromium(Ⅲ) complex. According to the results, it is found that nitrogen atoms of the cyclam ligand have a strong σ-donor character, while the NCS ligand has medium σ- and π-donor properties toward chromium(Ⅲ) ion.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3175-3180
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• 2014

A potentiometric sensor based on the 1-benzyl-3-(4-nitrophenyl) thio-urea was synthesized and tested as an ionophore in PVC based membrane sensor towards $SCN^-$ ions. This membrane exhibits a linear stable response over a wide concentration range ($1.0{\times}10^{-5}$ to $1.0{\times}10^{-2}M$) with a slope of -59.2 mV/dec., a detection limit of ${\log}[SCN^-]=-5.05$, and a selectivity coefficient for thiocyanate against perchlorate anion of ${\log}K^{pot}_{SCN^-j}=-0.133$. The selectivity series of the membrane is as follows: $SCN^-$ > $ClO_4{^-}$ > $I^-$ > $NO_3{^-}$ > $HSO_3{^-}$ > $Cl^-$ > $HSO_4{^-}$ > $F^-$ > $CH_3COO^-$ > $HCO_3{^-}$ > $Br^-$ > $H_2PO_4{^-}$ > $SO{_3}^{2-}$ > $SO{_4}^{2-}$ > $CO{_3}^{2-}$. The proposed electrode showed good selectivity and a good response for the $SCN^-$ ion over a wide variety of other anions in pH 6.0 buffer solutions and has a fast response time of about < 5s. The influences of the membrane by pH, ionophore, and plasticizer were studied.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.423-427
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• 2013

This research was carried out to identify the characteristics of the wastewater from coke oven gas (COG) purification process of the coke plant, and derive optimal operating conditions for the treatment of wastewater. The coke plant wastewater contains highly concentrated $S^{-2}$ and $SCN^-$ that are harmful to microorganisms, and their concentrations were 6.8~11.2 mg/L and 190~320 mg/L, respectively. When the $S^{-2}$ ion concentration was lower than 10 mg/L, $SV_{30}$ of active sludge was 280~ 340 mL and the sludge sedimentation velocity was very fast. But, when the $S^{-2}$ ion concentration was higher than 15 mg/L, $SV_{30}$ of the active sludge was 560~680 mL and the sludge sedimentation velocity was very slow. Also when the $SCN^-$ ion concentration was lower than 300 mg/L, $SV_{30}$ of the active sludge was 245~320 mL and the sludge sedimentation velocity was very fast. But, when the $SCN^-$ ion concentration was higher than 400 mg/L, $SV_{30}$ of the active sludge was 470~ 567 mL and the sludge sedimentation velocity was slow. To treat the wastewater generated by COG purification process of the coke plant effectively and to maintain microorganism activities in good conditions, the ion concentration of $S^{-2}$ and $SCN^-$ should be lower than 15 mg/L and 400 mg/L, respectively.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.208-214
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• 1989

A method for the simultaneous determination of copper and cobalt by spectrophotometry has been described. The procedure involves the co-extraction of Cu(Ⅱ) and Co(Ⅱ) from 0.3M HCl into methyl isobutyl ketone as the ion-pairs formed between their thiocyanate complexes and high molecular alkylamines such as Amberlite LA1, Alamine 336, and Aliquat 336. The extract shows the color development to have the maximum absorbances at two different wavelengths i.e., 480 nm for copper and 625 nm for cobalt. Since the spectra of the ion-pairs overlap each other, two simultaneous equations are used to obtain the concentrations from absorbances. Even small amount of Fe(Ⅲ) and Ni(Ⅱ) interferes with the determination of copper. The results of the analysis of samples are in good agreement with the results determined by separate methods within RSD 5.9%.