• Korean Chemical Engineering Research
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• v.58 no.2
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• pp.293-300
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• 2020

Eucheuma spinosum, red macro-algae, contains carrageenan as the major polysaccharide and is commercially produced in Indonesia, Malaysia, Philippines, China and Tanzania. In this study, E. spinosum was converted to sugar and platform chemicals (5-HMF, levulinic acid, formic acid) via FeCl₃-catalytic hydrothermal reaction. In addition, statistical methodology (3-level 3-factor Box-Behnken design) was applied to optimize and evaluate the effects of reaction factors (reaction temperature, catalyst concentration and reaction time). As a result of optimization, the concentration of 5-HMF was obtained to be 2.96 g/L at 160 ℃, 0.4 M FeCl₃ and 10 min. Optimal conditions of levulinic and formic acids were determined at 200 ℃, 0.6 M FeCl₃ and 30 min, and the concentrations were obtained to be 4.26 g/L and 3.77 g/L, respectively.

• Journal of the Korean Magnetics Society
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• v.26 no.6
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• pp.179-184
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• 2016

For an industrial spin-transfer torque (STT) MRAM, low switching current and high thermal stability are required, simultaneously. For this point of view, it is essential to find magnetic materials which satisfy high spin polarization and strong perpendicular magnetocrystalline anisotropy (MCA). In this paper, we investigate electronic structures and MCA energies of perovskite $CoFeX_3$ (X = O, F, S, Cl). For X = F and Cl, spin polarization at the Fermi level are 97 % and 96 %, respectively, which are close to a half metal. Furthermore, Co-terminated 5-monolayer (ML) $CoFeX_3$ (X = O, F, S, Cl) films show perpendicular MCA. In particular, the MCA energy of the Co-terminated $CoFeCl_3$ is about 1.0 meV/cell which is three times larger than that of a 5-ML CoFe film. Therefore, we expect to realize a magnetic material with high spin polarization and strong perpendicular MCA energy by utilizing group 6 and 7 elements in the periodic table, and to contribute to commercializing of the STT-MRAM.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.34-39
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• 2009

This study was carried out in order to investigate the decolorization and reduced sludge of real textile wastewater by coagulation process. The aim of the study was to verify the relation between decolorization and coagulants of real textile wastewater treatment processes. Coagulation processes were performed using $FeCl_3$, $FeSO_4$, and $Al_2(SO_4)_3$. Real textile wastewater has a mean concentration for BOD, COD, pH, color to be 800 mg/L, 600 mg/L, 9.7, and 102, respectively. From the experimental results, it was shown that the $FeCl_3$ exhibited higher decolorization at the operating conditions 335~2000 mg/L of coagulants and 500 mg/L NaOH dosage. The efficiency of color removal depended on the wastewater pH and concentration of coagulants.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.3
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• pp.45-56
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• 2020

Objectives This study was designed to investigate the effects of ChondroT on thrombus in FeCl₃-induced rats. Methods We exposed FeCl₃ to rat's carotid artery to induce thrombus. Specimens were divided in 5 groups; Intact, Control, ASA10 (aspirin 10 mg/kg), CT100 (ChondroT 100 mg/kg), and CT200 (ChondroT 200 mg/kg), each n=6. We investigated thromboxane, platelet activating factor (PAF), histological change, lipid metabolism, transaminase, leukocyte, erythrocyte and thrombocyte level. Results In ASA10, CT200 groups, there was significants decrease in both thromboxane level and total cholesterol level, compared to control group and there were significant histological changes of blood vessel, compared to control group. In CT200 group, there was significant decrease in PAF level, compared to control group (p<0.05). In ASA10, CT200 groups, triglycerides level tended to decrease, compared to control group. Conclusions Based on these results, it could be suggested that ChondroT was effective on thrombus in FeCl₃-induced rats, and further study is needed to conduct a rigorous clinical research.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.910-912
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• 2004

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1364-1368
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• 2008

The activity of the catalytic system composed of Fe$(acetylacetonate)_3$ (Fe$(acac)_3$), triphenylphosphine, and diethylaluminum chloride for the dimerization of bicyclo[2.2.1]hepta-2,5-diene (2,5-norbornadiene, NBD) to produce hexacyclic endo-endo dimer (hexacyclo[$7.2.1.0^{2,8}.1^{3,7}.1^{5,13}.0^{4,6}$]tetradec-10-ene, Hnn) was significantly enhanced by the presence of $AlCl_3$, especially at the molar ratios of NBD/Fe$(acac)_3$ of 500. XPS analysis of the catalytic systems clearly demonstrates that $AlCl_3$ facilitates the reduction of Fe$(acac)_3$ to form active species, Fe(II) and Fe(0) species. The layer separation was observed when [BMIm]Cl was used along with $AlCl_3$, but catalyst recycle was not very successful.

• Journal of the Korean institute of surface engineering
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• v.51 no.4
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• pp.214-217
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• 2018

Stainless steel grade 430 with a composition of Fe-17%Cr was corroded in $Na_2SO_4$ and ($Na_2SO_4+NaCl$) salts at 800 and at $900^{\circ}C$ for up to 20 h. It corroded mainly to $Cr_2O_3$, along with a small amount of $Fe_2O_3$ and $Fe_3O_4$. The formed oxide scales were neither dense nor compact enough owing to their ensuing dissolution into the salt during corrosion, which facilitated internal corrosion. Corrosion occurred faster at $900^{\circ}C$ than $800^{\circ}C$. NaCl in $Na_2SO_4$ aggravated the scale adherence.

• Resources Recycling
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• v.23 no.6
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• pp.22-29
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• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (100 mg/L), PVP($FeCl_3:PVP$ = 1 : 4, w/w) and Pd($FeCl_3:PdCl_2$ = 1 : 0.001, w/w) were used, iron nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• Korean Journal of Materials Research
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• v.10 no.7
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• pp.471-477
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• 2000

Corrosion behavior of Fe-Ni-Cr alloy in molten salts of LiCl and LiCl-$Li_2O was investigated in the tempera-ture range of $650~850^{\circ}C$. In the molten salt of LiCl, and internal oxidation of Fe occurred in the KSA(Kaeri Superalloy)-1 alloy without containing Cr, while a dense protective oxide scale of $LiCrO_2$ was formed in the KSA-4, Incoloy 800H and KSA-5 alloys. In the mixed molten salt of LiCl-$Li_2O$, internal oxidation of Fe and Cr took place in the KSA-1 and KSA-4 alloys, respectively. Non-protective porous oxide scales consisting of $LiCrO_2$ and Ni were formed in the Incoloy 800H and KSA-5. The corrosion rate of the alloys increased with the increase in Cr content and the corrosion rate followed the parabolic law for the alloy containing Cr content less than 8%, and the linear law for the alloy containing Cr content more than 8%. Such a corrosion behavior of the alloy in the mixed molten salt of LiCl-$Li_2O$ was interpreted in terms of the basic fluxing mechanism of protective oxide scale of $Cr_2O_3$.

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.11-19
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• 2004

Chlorinated and nitroaromatic compounds are non-degradable substances that are extremely toxic and are known to be carcinogens and mutation causing agents. Moreover, the half-lives of substances such as carbon tetrachloride, hexachloroethane and nitroaromatic compounds are several decades. In this study, the optimal conditions to detoxify chlorinated compounds by the reductive degradation were investigated. The following results were obtained in the reductive degradation of CCl$_4$, C$_2$Cl$\_$6/, C$_2$HCl$\_$5/, C$_2$Cl$_4$, and C$_2$HCl$\_$5/ by using Fe, FeS and FeS$_2$ as mediators. CCl$_4$ was reduced to CH$_2$Cl$_3$ and CH$_2$Cl$_2$in anaerobic conditions when FeS was used as a mediator. While the reduction of CCl$_4$ to CHCl$_3$ was rapidly proceeded, the reduction of CHCl$_3$ to CH$_2$Cl$_2$ was occurred slowly. Further reduction to CH$_3$Cl was not observed. Unlike CCl$_4$, C$_2$Cl$\_$6/ was degraded to C$_2$HCl$\_$5/, C$_2$Cl$_4$. C$_2$HCl$_3$ and cis-1,2-C$_2$H$_2$Cl$_2$ by complicated pathways such as hydrogenolysis, dehalo-elimination and dehydrohalogenation. A small amount of C$_2$HCl$\_$5/ was detected only in the early stages of the reduction. However, majority of the C$_2$Cl$\_$6/ was reduced to C$_2$Cl$_4$. cis-1,2-C$_2$H$_2$C1$_2$ was the only product among other possible isomers.