• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.115-116
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• 2001

본 연구에서는 이온 크로마토그래피로 환경오염물질들을 분석하고자 할때의 단전들을 해소하기 위하여 모세관 컬럼 이온 크로마토그래피를 개발하였다. 모세관 컬럼은 두가지 형태로 개발하였는데 하나는 packed capillary 컬럼이며 다른하나는 open tubular capillary 컬럼이다. 또한 위와 같이 모세관 컬럼을 개발하여 사용하게됨을써, 부수적으로 펌프, 시료주입기, 억압장치 그리고 전도도 셀 등을 모두 적은 부피를 다룰 수 있는 구조로 바꾸어 주었다. 따라서 본 연구의 결과로 미량환경오염 물질의 분석에 모세관 컬럼 이온크로마토그래피를 이용할 수 있는 가능성을 확인할 수 있었고, 나아가 이온 크로마토그래피의 소형화로 현장에서 직접 분리, 분석을 할 수 있으리라 기대된다.

• Analytical Science and Technology
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• v.8 no.3
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• pp.265-272
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• 1995

Schiff base ligand columns and glow discharge detector have been developed for the trace analysis of metal ions desolved in water. Various types of hydrazide Schiff base ligands have been used and, additionally, they were examined as a filling material of a HPLC column. The hydrazide Schiff base ligands used were N, N'-oxalybis(salicylaldehydrazone) (OBSH), N, N'-malonylbis(salicylaldehydrazone) (MBSH), and N, N'-succinylbis(salicylaldehydrazone) (SBSH). A mixture of Schiff base ligand and poly(styrene divinylbenzene) was examined and it showed a smooth flow of solution. The OBSH-polymer column demonstrated different effluent factors for different metal ions. Metal ions in eluates were detected by Hollow Cathode Glow Discharge-Atomic Emission Spectrometry(HCGD-AES). HCGD-AES showed good sensitivity and selectivity. This is only the preliminary results of new OBSH-polymer column and glow discharge detector.

• Journal of the Korean Chemical Society
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• v.45 no.2
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• pp.143-148
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• 2001

In this study, open tubular capillary columns for ion charomatography were developed to analyze trace amount of ions in samples. When small I,D. capillary column length is 1.0~5.0 m. The capillary columns were made using fused silica capillary(I.D:50㎛) and DMEOHA latex particles. The new conductivity cell and suppressor were also developed and made for capillary column ion chromatography. When several anions(fluoride, nitrite, nitale,chlorate,phosphte, sulfate) were analyzed using these capillary columns. reproducible and good chromatograms were obtained.

• Analytical Science and Technology
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• v.12 no.2
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• pp.89-93
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• 1999

In this study, conductivity cell and suppressor for micro-column ion chromatography were developed to analyze ions in small columns of samples. With a capillary column, the flow rate of the mobile phase is so small (usually $5{\sim}20{\mu}L/min$) that the usual conductivity cell can not be used. Therefore, we developed a new type of conductivity cell and suppressor which have small inner volumes. The conductivity cell was made with two Pt hypodermic needles (i.d. 0.010 mm) which are slightly separated (about $2{\mu}m$), and the suppressor was made of Nafion tubings. When several anions(fluoride, nitrite, nitrate, chlorate) were analyzed using developed conductivity cell and suppressor, a good chromatogram was obtained.

• Analytical Science and Technology
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• v.12 no.6
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• pp.521-527
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• 1999

In this study, capillary columns for ion chromatography were developed to analyze trace amount of ions in samples. When small I.D. capillary columns are used in ion chromatography, the typical flow rate of the mobile phase is $5{\sim}15{\mu}L/min$ and the typical column length is 50~150 mm. The capillary columns were made using RSL-300 fused silica capillary(I.D.: 0.53 mm, O.D.: 0.67 mm) and AG14 column resin(support : polystyrene-divinylbenzene, functional group : alkyl quaternary ammonium). The new conductivity cell and suppressor were also developed and made for capillary column ion chromatography. When several anions (fluoride, nitrite, nitrate, chlorate) were analyzed using these capillary columns, reproducible and good chromatograms were obtained.

• Analytical Science and Technology
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• v.19 no.5
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• pp.383-388
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• 2006

Simple post-wash method by ion chromatography (IC) was established for the rapid and precise determination of fluoride ion in wastewater from mine in fluorite mineralized area. High sulfate in sample was retained in a pre-column and less strongly held fluoride ion was transferred to the principal separation system using modified conventional IC with switching technique. An analytical column with high capacity (AS 9 HC) was used as a pre-column to retain the amount of high sulfate. A guard column (AG 14) as a separation column was used to increase the response of fluoride and reduce the system pressure. According to the recovery of fluoride ion with one detector and the observation of sulfate peak with another conductivity detector, the optimum switching time of 10-port chromatographic injector was 4.3 min. The limit of detection (S/N = 3) of fluoride in synthetic solution containing $500mg\;L^{-1}$ sulfate was $2.4{\mu}g/L$, with $25{\mu}L$ sample volume.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.275-282
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• 1981

A simple semiquantitative procedure was developed for the determination of sub-ppm level of chromium(VI) in aquatic samples by using an analytical micro-column packed with diphenylcarbazide(DPC) gel beads. DPC gel beads were prepared by swelling XAD-2 resin(115∼150 mesh in dry condition) in ethanol for 10min, packing into a glass column(1.5 mm bore, 65nm length) and adsorbing 1ml of ethanol solution of $2{\times}10^{-3}M$ DPC for 20min at room temperature. When 0.5ml of ethanol solution containing chromium(VI) was passed through the DPC gel column for 40min, the original white color of the reagent gel turned to red-violet from the up-stream of the column. As the length of colored band was proportional to the total amount of chromium(VI) in the sample solution passed through the column, the concentration of chromium(VI) could be determined from the calibration line which had been prepared by using the standard solution. Chromium(VI) ion as small as from 0.1 to 0.8 ppm could be determined with ${\pm}5{\sim}{\pm}15{\%}$ relative errors. Since other interfering cations were few, 100-fold excess of Fe(III), 50-fold excess of Cu(II) could be masked with EDTA. This method was successfully applied to the analysis of chromium(VI) in industrial effluents.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.35-44
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• 1997

A column study using artificial acid rain was conducted to evaluate the buffering capacities in soil layer and host rock. In an effort to compare the effect of composition of host root two valleys of which compositions of host rock are different were chosen within the study area and the pHs of the water flowing in the valleys were measured from May, 1996 to October, 1996. The pHs of the artificial acid rain prepared by adding appropriate amounts of both sulfuric and nitric acids to distilled water were 3, 4, and 5, and the column effluents were analyzed for major cations and anions. The cation exchange capacities(CECs) of A Horizon and the B Horizon were 9.68 and 6.16 meq/100g, respectively, Compared to the B Horizon, the pH in the column effluent of A Horizon with larger CEC was higher. The sums of $Ca^{2+}$, $Mg^{2+}$, $Na^{+}$in the column effluents gradually decreased, indicating the loss of CEC by acid rain. The field study showed that pHs of the surface water in the valleys increased as the water flows downwards. The magnitude of this buffering capacity was greater for the valley in which smectite in addition to kaolinite and illite was a weathered product of host rocks. This also indicates that host rock as well as soil layer retains the buffering capacity.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1192-1197
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• 2006

Adsorbability of ionic and nonionic pharmaceuticals was studied using granular activated carbon(GAC). In a batch adsorption test of muticomponent solution, 500 mg/L of GAC dose removed all target compounds between 94 and 98% at initial concentration of 10 ${\mu}g/L$. Adsorption of ionic pharmaceuticals increased as pH was lowered toward to pKa, however adsorption capacity of nonionic pharmaceuticals showed insignificant variation with the changing pH. The enhanced adsorption capacity of ionic pharmaceuticals at lower pH was attributed to the corresponding increase in the molecular form of ionic pharmaceuticals with carboxylic group at low pH. In addition, decrease of pH increased hydrogen ion concentration in the bulk solution and the protons bound to the available sites on the carbon enhanced the removal of the ionic pharmaceuticals from solution. After 40 days of continuous operation, GAC column showed the removal of target compounds were removed by $93{\sim}99%$ at 15 min of EBCT mainly due to adsorption mechanism of GAC. At shorter EBCT than 15 min, breakthrough of CA, IBP and GFZ occurred earlier than the other ionic and nonionic pharmaceuticals. effect of EBCT on adsorption of nonionic pharmaceuticals was greater than ionic ones. This study showed that persitent pharmaceuticals found in drinking water treatment could be effectively controlled by adsorption in GAC process.

• Journal of Soil and Groundwater Environment
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• v.6 no.1
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• pp.13-21
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• 2001

The characteristics of $Co^{2+}$ removal in the kaolinite column were analyzed by electrokinetic remediation. Ethanoic buffer was injected in the kaolinite column and $CH_3$COOH was continuously added to the cathode reservoir to restrain the pH increase. The pH of the cathode of the kaolinite column was 4.0 at first. Since it was controlled to be under 6.5 after 43.6 hours due to ethanoic buffer, precipitation of ${Co(OH)}_2$ was not formed in the column. Effluent rate increased with time and $Co^{2+}$ removal in the column at initial time was mainly controlled by ion migration. 13.1% of total $Co^{2+}$ in the column was removed after 10 hours, the 46.8% of total $Co^{2+}$ after 20.8 hours, and the 71.7% of total $Co^{2+}$ after 30.1 hours, the 94.6% of total $Co^{2+}$ after 43.6 hours, Meanwhile, the residual concentrations in the column calculated by the developed model were similar to experiment results.