• Bulletin of the Korean Chemical Society
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• 제16권4호
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• pp.310-315
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• 1995

The heterobimetallic anion, (OC)5CrMn(CO)5-M+ (M+=Na+, PPN+), which has a donor-acceptor metal-metal bond1, was reacted with allyl bromide to yield BrCr(CO)5- and Mn(CO)5(CH2CHCH2). The reaction mechanism has been proposed in terms of the consecutive reaction pathway in which Cr(CO)5(THF) is an important intermediate leading to the corresponding product. Counterion effect on this reaction was also evaluated and the results were compared with those of the corresponding reaction of the mononuclear carbonyl anion, Mn(CO)5-.

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.183-188
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• 1998

Incorporation of metalloporphyrins into polypyrrole (PPy) film was achieved either by electropolymerization of pyrrole in the presence of metal-tetra(sulfonatophenyl)porphyrin anion (MTSPP, M=Co, Fe) or by metalizing hydrogenated tetra(4-sulfonatophenyl)porphyrin anion (H2TSPP) doped into PPy through ion-exchange. Electrochemical reduction of oxygen on the PPy doped with metallo porphyrin (PPy-MTSPP) was studied in acidic and basic solutions. Oxygen reduction on PPy-MTSPP electrodes appeared to proceed through a 4-electron pathway as well as a 2-electron path. In acidic solutions, the overpotential for O2 reduction on PPy-CoTSPP electrode was smaller than that on gold by about 0.2 V. In basic solutions the overpotential of the PPy-CoTSPP electrode in the activation range was close to those of Au and Pt. The limiting current was close to that of Au. However, polypyrrole doped with cobalt-tetra(sulfonatophenyl)porphyrin anion (PPy-CoTSPP) or with iron-tetra(sulfonatophenyl)porphyrin anion (PPy-FeTSPP) was found to have limited potential windows at high temperatures (above 50 ℃), and hence the electrode could not be held at the oxygen reduction potentials in basic solutions (pH 13) without degradation of the polymer.

• 폴리머
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• 제36권5호
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• pp.564-572
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• 2012

본 연구에서는 막축전식 탈염(membrane capacitive deionization, MCDI) 공정용 음이온교환막의 제조를 위하여 vinylbenzyl chloride-co-ethyl methacrylate-co-styrene(VBC-EMA-St) 공중합체를 합성하였으며, 아민화 반응과 열처리를 통하여 음이온교환막을 제조하였다. 구조확인을 위하여 FTIR 분석을 하였고, GPC와 TGA를 통하여 합성한 고분자의 분자량과 분자분포, 열안정성을 분석하였으며, 함수율 및 이온교환용량을 측정하였다. 또한 LCR meter로 전기저항을 측정하고, MCDI 공정에 적용하기 위하여 제조한 음이온교환막을 충방전 시험 측정하였다. 이온교환용량, 함수율, 전기저항, 분자량은 각각 1.69 meq/g, 23.7%, 1.61 ${\Omega}{\cdot}cm$, $3.4{\times}10^4$ g/mol이었으며, CDI 충방전 시험 결과 상용화막인 AMX보다 우수한 성능을 나타내었다.

• Rapid Communication in Photoscience
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• 제4권3호
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• pp.67-69
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• 2015

FTIR spectroscopy has been employed to investigate the variation of anion-water hydrogen bonding in 1-butyl 3-methyl imidazolium tetrafluoroborate ([Bmim][$BF_4$]) ionic liquid caused by addition of organic co-solvents with various polarities. The variation was estimated by probing band shape and intensity of the OH stretching vibration of trace water present in ionic liquid at $3400-3800cm^{-1}$. The presence of polar aprotic co-solvent in ionic liquid dramatically reduces the absorptivity of the OH stretch band, indicating that the co-solvent changes the nature of anion-water hydrogen bond drastically, which might be responsible for the reduction of the viscosity of ionic liquid in the presence of the co-solvent.

• KSBB Journal
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• 제6권2호
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• pp.207-213
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• 1991

In this study poly (1-methyl-4-vinylpyridinium iodide-co-styrene) membrane with pyridinium cation as a fixed carrier was synthesized and the transport characteristics of the membrane was examined over various factors. As the concentration of the fixed carrier in the membrane was increased, the water content was increased. Meanwhile, the counter current of the organic anion and the chloride ion, the following results were obtained. Initial flux of Cl-, organic anion and Na+ decreased with the increasing thickness of membrane, and as the concentration of the fixed carrier increases, the initial flux of Cl- and organic anion increase but the initial flux of Na+ decreased. The flux equation of the organic anion, CCl3COO- was obtained from saturation kinetics as follows;$V_{o}=\frac{(8.67{\times}10^{-5}){\cdot}[NaCl]}{9.63{\times}10^{-2}+[NaCl]} mol/cm^2h$

• 폴리머
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• 제39권1호
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• pp.157-164
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• 2015

본 연구에서는 수중 질산성 질소($NO{_3}^-$) 제거용 음이온교환막 제조를 위하여 poly(vinylimidazole-co-trifluoroethylmethacrylate-co-divinylbenzene)(PVTD) 공중합체를 제조하고, quaternization 반응을 통하여 관능기를 도입하기 위한 최적화 반응온도, 반응시간, 관능화농도 조건을 규명하였다. 제조한 음이온교환막의 구조 확인과 분자량 측정을 위하여 FTIR, $^1H$ NMR, 스펙트럼 분석과 GPC 분석을 하였다. 또한 제조한 음이온교환막의 함수율, 팽윤율, 전기저항, 이온교환용량과 같은 기본물성을 측정하였다. 또한 수중 질산염 제거율과 선택성을 확인하기 위하여 막의 음이온 투과성을 측정하여 질산성 질소의 선택성을 확인하였다. 최적 함수율, 전기저항, 이온교환용량은 각각 51.2%, $5.4{\Omega}{\cdot}cm^2$, 1.04 meq/g으로 측정되었다.

• 대한화학회지
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• 제24권5호
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• pp.380-392
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• 1980

6배위, 작은 스핀 철(Ⅱ)착화합물, [Fe$(DH)_2B_2$]과 [Fe(D$H_2$B(CO)]($(DH)_2$=$(CHDH)_2$-(bis(1,2-cyclohexadinedioximato)(bivalent anion),$(DPGH)_2$(bis(diphenylglyoximato) bivalent anion), $(F{\alpha}DH)_2(bis(furil-{\alpaha}$-dioximato) bivalent anion), B = neutral monodentate nitrogen base)을 합성하여 이들의 물리적 성질을 적도 방향의 리간드, $(DH)_2$에 관하여 조사하였다. 적외선 스펙트럼 분석결과, [Fe$(DH)_2B(CO)] 중에서 {\pi}$-전자받게 리간드인 CO의 신축진동수 크기의 순서는 $(F{\alpha}DH)_2$ > $(DPGH)_2$ > $(CHDH)_2 화합물의 순서이고 [Fe$(DH)_2(NH_3)_2$]중에서 ${\pi}$-전자받게 성질이 없는 $NH_3$의 신축진동수 크기의 순서는 그 반대인 $(CHDH)_2$ > $(DPGH)_2 > $(F{\alpha}DH)_2$ 화합물임을 관찰하였다. 이상의 결과와 철-질소(옥심) 및 철-질소(B)의 신축진동수 데이타로부터 다음을 알았다. 즉 $(CHDH)_2$중의 질소원자들은 $(DPGH)_2$ 및 $(F{\alpha}DH)_2$ 중의 질소원자들보다 염기도는 크지만 ${\pi}$-전자받게의 경향은 적다. 상기 착물들의 전자스펙트럼을 조사한 결과 $(DH)_2의 염기도가 증가함에 따라 철로부터 $(DH)_2$로 일어나는 전하이동띠의 에너지가 증가함을 알았다.

• 폴리머
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• 제35권6호
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• pp.586-592
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• 2011

본 연구에서는 전바나듐 레독스-흐름 전지용 음이온교환막의 제조를 위하여 vinylbenzyl chloride-co-styreneco-hydroxyethyl acrylate(VBC-co-St-co-HEA) 공중합체를 합성하였으며, 아민화 및 가교 반응을 통하여 음이온교환막을 제조하였다. 구조확인을 위하여 FTIR, $^1H$ NMR, TGA, GPC 분석을 하였으며, 음이온교환막의 함수율, 이온교환용량, 전기저항, 이온전도도 및 전바나듐 레독스-흐름 전지의 효율을 측정하였다. 음이온교환막의 이온교환용량, 전기저항, 이온전도도는 각각 1.17 meq/g, $1.9{\Omega}{\cdot}cm^2$, 0.009 S/cm이었으며, 전바나듐 레독스-흐름 전지 효율 실험 결과 충 방전효율, 전압효율 및 에너지효율은 각각 99.5, 72.6, 72.1%이었다.

• Bulletin of the Korean Chemical Society
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• 제15권7호
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• pp.537-541
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• 1994

The reaction of the heterobimetallic anion, ${(OC)_5CrMn(CO)_5^-M^+ (M^+=Na^+, PPN^+)\;with\;CH_3I$ was proven to be overall 1st order with respect to $[(OC)_5CrMn(CO)_5^-]$ This reaction mechanism may be described in terms of the consecutive reaction pathway in which Cr$(CO)_5$(THF) may be an important intermediate, leading to the corresponding products such as MeMn$(CO)_5\;and\;ICr(CO)_5^-$, accordingly. The counterion effect on this reaction was also elucidated.

• Journal of Nuclear Fuel Cycle and Waste Technology
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• 제1권1호
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• pp.57-63
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• 2013

Natural green rust (GR) can retard the migration of anions through geological media because it has a Layer Double Hydroxyl (LDH) structure with a positive charge. In this study, the sorption behaviors of anions such as selenite ($Se(IV)O{_3}^{2-}$), selenate ($Se(VI)O{_4}^{2-}$), and iodide ($I^-$) onto green rusts with different structures, i.e., GR($Cl^-$) and GR($CO{_3}^{2-}$), were investigated by conducting batch sorption experiments in an anoxic condition. Experimental results showed that selenite was mostly sorbed onto GR($CO{_3}^{2-}$) and then partly reduced to metal selenium, Se(0). However, little selenate and iodide was sorbed onto GR($CO{_3}^{2-}$) while some iodide was sorbed onto GR($Cl^-$). It is presumed from the experimental results that the major sorption mechanism of $SeO{_3}^{2-}$ and $I^-$ onto green rusts is the anion exchange reaction with the anions existing in the interlayer of the rusts. Green rust, therefore, can play an important role in the retardation of anions migrating through deep geological environments owing to its LDH structure with a high anion exchange capacity.