• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.373-378
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• 2003

As a part of assessment of the structural material for the molten salt handling system, corrosion behavior of austenitic alloys, Fe-base and Ni-base in the molten salt of $LiCl-Li_2O_2$ was investigated in the range of temperature; 650~$725^{\circ}C$, time; 24- 168h, $Li_2O$; 3wt%, mixed gas; Ar-10%$O_2$. In the molten salt of $LiCl-Li_2O_2$, Ni-base alloys showed higher corrosion resistance than Fe-base alloys. Fe-base alloy with low Fe and high Ni contents exhibited better corrosion resistance. The scales of $Cr_2O_3$, $FeCr_2O_4$ on Fe-base alloys were showed, and $Cr_2O_3$, $NiFe_2O_4$ on Ni-base alloys were also showed.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.648-654
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• 1993

$[M(cyclam)X_2]Y(M=Co^{3+},\;Fe^{3+},\;Mn^{3+}\;:\;X=Cl-^,\;Br^-,\;NCS^-\;:\;Y=Cl^-,\;Br^-,\;NCS^-),\;[Co(trans-14-diene)X_2]Y(X=Cl^-,\;Br^-\;:\;Y=ClO_4^-)\;and\;[Co(trans-14-diene)](ClO_4)_2$ were able to activate an molecular oxygen under sodium borohydride. 2,4-di-tert-butylphenol and 2,6-di-tert-butylphenol reacted with activated molecular oxygen to give 2,4-tert-butyl-1,6-benzoquinone(BQ) and 3,5,3',5'-tetra-tert-butyldiphenoquinone(DPQ). The saturated tetraazamacrocyclic complexes, $[Co(cyclam)X_2]Y$, were more an effective catalyst than $[Co(trans-14-diene)X_2]Y$ the unsaturated complexes in the formation of BQ and DPQ. The mole ratio of $O_2$ vs. catalyst $(O_2/M)$ for $[Co(cyclam)X_2]Y$ and [Co(trans-14-diene)X_2]Y$ was 1/1, while it was 1/2 for $[M(cyclam)Cl_2]Cl(M=Fe(III),\;Mn(III))$. The results suggested that Co(III)-macrocyclic complexes activated molecular oxygen as superoxolike ${O_2}^-$ and $[M(cyclam)Cl_2]Cl(M=Fe(III),\;Mn(III))$ activated that as peroxolike $O_2^{2-}$.

• Journal of the Korean Ceramic Society
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• v.19 no.3
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• pp.223-228
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• 1982

For the preparation of ferroxidure BaO.5.5 $Fe_2O_3$ with high coercive force, the green and calcined coprecipitates, which were obtained by neutralizing the mixed salt solution $FeCl_2-BaCl_2$ and $FeCl_3-BaCl_2$ with alkali solution $NaOH-Na_2CO_3$, were investigated about the thermal reaction, crystal growth, and the magnetic properties of the sintered specimens. The very single-domain crystallites of Ba-ferrite with high coercive force are formed from the coprecipitate of amorphous $Fe(OH)_3$ and amorphous $BaCO_3$ at lower temperature than that of subnucleus crystalline $\delta$-FeOOH and amorphous $BaCO_3$.

• Clean Technology
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• v.23 no.2
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• pp.158-162
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• 2017

$FeCl_3$ solution has been used as an etchant for metal etching such as Fe, Cu, Al and Ni. In the etching process, $Fe^{3+}$ is reduced to $Fe^{2+}$ and the etching efficiency is decreased. Waste $FeCl_3$ etchant has environmental, economic problems and thus the regeneration of the etching solution has been required. In this study, HCl was mixed with the $FeCl_2$ solution and then, $H_2O_2$, $NaClO_3$ were added into the mixed solution to oxidize the $Fe^{2+}$. During the oxidation process, oxidation-reduction potential (ORP) was measured and the relationship between ORP and oxidation ratio was investigated. The ORP is increased with increasing the concentration of $H_2O_2$ and $NaClO_3$, and then the ORP is decreased with oxidation progress. Such a behavior was in good agreement with Nernst's equation. Also, the oxidation efficiency was about 99% when a sufficient amount of HCl and $H_2O_2$, $NaClO_3$ were added.

• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.65-68
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• 2000

A $\mu-oxo$ diiron(III) complex and two bis( $\mu-alkoxo)$ diiron(III) complexes with biomimetic tripodal ligand containing mixed N/O donor atoms were synthesized using a mononuclear iron(III) complex as starting material. Depending on the amounts and kinds of bases used, we obtained various kinds of diiron (III) complexes. The reaction of $[$Fe^{III}$(Hbbea)Cl_2]Cl$, 1, with an equivalent amount of $KO_2$ or NaOAc produced $[$Fe^{III}$_2O(Hb-bea)_2Cl_2]Cl_2$, 2. An additional equivalent amount of NaOBz or NaOAc converts complex 2 to complex 3 or complex 4 depending on the base used. The addition of two equivalent amounts of NaOBz orNaOAc directly converts complex 1 to $[$Fe^{III}$_2(bbea)_2(OBz)_2]Cl_2$, 3, or $[$Fe^{III}$_2(bbea)_2(OAc)_2]Cl_2$, 4, depending on the base used. Crystal data are as follows: [$Fe^{III}_2O(Hbbea)_2Cl_2]Cl_2$, 2: monoclinic space group $$P2_1/n$$, a = 8.421 (1) $\AA$, b = 18.416 (2) $\AA$, c = 13.736 (1) $\AA$, $\beta$ = 104.870 $(7)^{\circ}$, V = 2058.9 (4) $\AA^3$, Z = 2, R1 = 0.0469 and wR2 = 0.1201 for reflections with I > 2 ${\sigma}$(I).

• Korean Journal of Crystallography
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• v.9 no.2
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• pp.107-113
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• 1998

Ar하에서 trans-FeHCl(dppe)2, 1을 4-chlorobutyronitrile에 녹이면, 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2]Cl, 2가 생성되고, 2는 NaBF4와 반응하여 착물 trans-[FeH(NCCH2CH2CH2Cl)(dppe)2][BF4], 3로 변환된다. 착물 3의 결정학 자료: 단사정계 공간군 P21/c, a=13.540(2) , b=17.058(3) , c=21.853(4) , β=90.15(1)o, Z=4, R(wR2)=0.0524(0.1239).

• Bulletin of the Korean Chemical Society
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• v.18 no.12
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• pp.1308-1311
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• 1997

• Economic and Environmental Geology
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• v.46 no.1
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• pp.21-28
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• 2013

In order to optimize gold leaching from refractory sulfide concentrate, a HCl-NaClO-$FeCl_3$ solution with varying attributes was applied to the roasted concentrate from Uil mine. The gold from Uil mine occurs in the form of invisible gold that is difficult to leach. The results of the gold leaching experiments showed that the best gold leaching parameters were $550^{\circ}C$ of roasting temperature, 2.0 M of concentration, 1.0% of pulp density, and $70^{\circ}C$ of leaching temperature. It is confirmed that the HCl-NaClO-$FeCl_3$ solution was an environmentally friendly method to leach gold and silver from the refractory sulfide concentrate as an alternative lixiviant to cyanide.

• Journal of Powder Materials
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• v.6 no.4
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• pp.294-300
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• 1999

This study was carried out to investigate the possibility whether Metal Injection Molding (MIM) process could be applied to 95wt.%W-3.5wt.%Ni-1.5wt.%Fe heavy alloy in order to obtain an intricate shape. Methylcellulose was used in the injection molding for binder. $FeCl_2-4H_2O$ was added in solvent substituting Fe powder and $FeCl_2$ was doped on W-Ni premixed powder. When $FeCl_2-4H_2O$ was added in solvent, the binder separation occurred for injection molding so that the matrix content was changed. Such problem was solved when $FeCl_2$ was doped. In this study. the debinding process did not affect residual carbon content. The sintered microsouctures as addition methods of Fe element and the sintering temperature from $1420^{\circ}C$ to $1470^{\circ}C$, which are around the temperature of liquid phase formation, were observed.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.579-581
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• 2010

Solid silica supported ferric chloride ($SiO_2-FeCl_3$) catalyzed one-step synthesis of various benzimidazoles from o-phenylenediamine and aldehydes using $H_2O_2$ as the oxidant. The salient features of this method are simple and convenient procedure, easy purification and shorter reaction times.