• Analytical Science and Technology
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• v.20 no.6
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• pp.496-501
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• 2007

The 242.795 nm on ICP-AES for the gold analysis was the most sensitive wavelength which was also interfered severely by the spectra of other metal ions such as manganese, chromium, cobalt, and iron. In order to analyze the gold in ore, the gold must be separated from the interfering ions. The best solvent for separation of gold in ore solution was 10 % n-hexane contained MIBK mixed solvent. The gold recovery was 97.5 % from mixed metal solution contained about 2 M $HNO_3$ and 0.5 M HCl.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.327-332
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• 1999

Manganese (Mn) oxides in soils have been a research subject since they react with nutrients and contaminants and Mn itself is an essential element for plant growth. Birnessite was synthesized in the presence of iron (Fe) in the precipitating solution. Influence of Fe, one of common elements in soils, on crytallinity, morphology, and chemical reactivity of birnessite was examined using X-ray diffraction (XRD), electron microscope, canon exchange capacity (CEC), and chromium (Cr) oxidation capacity. With increasing Fe concentration in the precipitating solution, crystallinity and crystal size decreased. Hexagonal plates of the birnessites formed at low Fe concentration were dominant and replaced more and more by aggregate of small particles with increasing the Fe concentration. There is no significant change in CEC with changing the Fe concentration. Chromium oxidation capacity of the birnessite increased with increasing the Fe concentration. Iron in the precipitating solution poisoned crystal growth by adsorption on the surface and increased nucleation. Since Fe is a common constituent under pedogenic environment and Fe and Mn oxides often coexist in Mn oxide nodules, the birnessite with small particle, low crystallinity, and high chemical reactivity is the form which is more likely to be formed in soils. The high CEC ($140cmol_ckg^{-1}$) and oxidation capacity of birnessite indicate that birnessite can be used in environment and agriculture.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.281-295
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• 2010

This paper deals with magnetic susceptibility, mineralogy, soil properties (pH, EC, CEC, loss on ignition), iron and manganese oxides, the content and partitioning of heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn), and their mutual relationship in the soil samples of an unpolluted, abandoned mine area, and industrial complex area. The various minerals derived from weathered bedrock were identified by X-ray diffraction in the unpolluted soil samples, except for the magnetic minerals. XRD analysis also revealed the existence of hematite and magnetite related to mine tailings and waste rocks in the abandoned mine area samples. The industrial complex area samples had carbonate minerals, such as calcite and dolomite, that might be due to anthropogenic deposition. The sum of the reducible, oxidizable, and residual fractions was over 80% for the abandoned mine area samples and over 50% for the industrial complex area samples using the sequential extraction method. The industrial complex area samples had a relatively high carbonate fraction that was associated with carbonate minerals. The content of aqua regia-extractable Fe, Mn, As, and Zn had a high positive correlation with the content of the dithionite-citrate-bicarbonate (DCB)-extractable method related to Fe/Mn oxide phases. The 54% and 58% of aqua regia-extractable Fe and As content, respectively, acted together with the concentrations of the DCB-extractable phases. Magnetic susceptibility values of total samples ranged from 0.005 to $2.131{\times}10^{-6}m^3kg^{-1}$. The samples including iron oxide minerals, such as hematite and magnetite, had a high magnetic susceptibility. The magnetic susceptibility showed a significant correlation with the heavy metals, Cd (r=0.544, p<0.05), Cr (r=0.714, p<0.01), Ni (r=0.645, p<0.05), Pb (r=0.703, p<0.01), and Zn (r=0.496, p<0.01), as well as Fe (r=0.608, p<0.01) and Mn (r=0.615, p<0.01). The aqua regia-extractable Fe and Mn content had a significant positive correlation with Cd, Cr, Cu, Ni, and Zn. However, the DCB-extractable Fe and Mn content had a significant positive correlation with As and Ni, indicating that the heavy metals were associated with Fe and Mn oxide minerals.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.2
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• pp.85-92
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• 2011

Evaluation of the removal efficiencies of Fe(II) by reactive sand media coated with manganese (MCS), iron (ICS) and both of iron and manganese (IMCS) was investigated as functions of solution pH ranging from 2 to 9, reaction time and concentration of Fe(II) in a batch reactor using each reactive medium and additional oxidants such as $KMnO_4$ and NaOCl. When only Fe(II) was present in solution without any reactive medium, removal of Fe(II) was quite low below pH 5 due to a slow oxidation of Fe(II) and/or negligible precipitation but greatly increased above pH 5 due to a rapid oxidation of Fe(II) and subsequent precipitation of oxidized Fe species. ICS showed negligible efficiency on the removal of Fe(II) through adsorption. However, an efficient removal of Fe(II) was observed at low solution pH in the presence of IMCS or MCS through rapid oxidation and subsequent precipitation. Removal efficiency of Fe(II) by IMCS in the presence or absence of NaOCl was quite similar. Removal rate of Fe(II) by IMCS and additional oxidants gradually increased as the solution pH increased. From the kinetic experiments, removal pattern of Fe(II) was better described by pseudo-second-order equation than pseudo-first-order equation. A rapid removal of Fe(II) using IMCS in the presence of $KMnO_4$ was observed in the first 10 min. The initial removal rate of Fe(II) using $KMnO_4$ was 14,286 mg/kg hr. In case of using NaOCl, the removal of Fe(II) occurred rapidly in the first 6 hrs and then reached the near-equilibrium state. Removal of Fe(II) on IMCS was well expressed by Langmuir isotherm and the maximum removal capacity of Fe(II) was calculated as 1,088 mg/kg.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.51-58
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• 1980

Sixteen species of algae (4 species of green algae, 5 species of brown algae and 7 species of red algae) were collected from the coast of Chungmu, Gyeongnam, from June to October, 1976. The content of minerals in algae were analyzed by Atometic Absorption Spectrophotometer. The results were as followed 1) The content of Iron and Nickel in green algae were abundant, and those of Lead, Nickel and Manganese in brown algae were low. 2) The content of Cadmium were in the range of 0.58-1.04ppm (average: 0.85ppm) in green algae, 0.32-2.10ppm (average: 1.08ppm) in brown algae and 0.54-1.70ppm (average: 1.04ppm) in red algae. The content of Cadmium were in the range of 0.3-0.6ppm in laver, Porphyra tenera, sea mustard, Undaria pinnatifida, and tangle, Laminaria japonica, but its content was lower than those expected. 3) The content of Lead were in the range of 0.67-1.40ppm (average: 1.03ppm) in green algae, 0.60-1.00ppm (average: 0.82ppm) in brown algae, 0.56-2.40ppm (average: 1.28ppm) in red algae and its content in algae were lower than in fish and shellfish. 4) The content of Copper were in the range of 10.8-24.2ppm (average: 18.95ppm) in green algae, 7.4-24.6ppm (average: 18.16ppm) in brown algae, 6.4-31.2ppm (average: 19.94ppm) in red algae and those content were considerably abundant except for some algae. 5) The content of Nickel were in the range of 5.4-16.6ppm (average: 9.1ppm) in green algae, 1.0-4.4ppm (average: 2.32ppm) in brown algae and 0.7-4.6ppm (average: 2.59ppm) in red algae. 6) The content of Iron were in the range of 686.4-1159.0ppm (average: 916.5ppm) in green algae, 131.0-499.2ppm (average: 310.16ppm) in brown algae and 156.0-530.4ppm (average: 248.2ppm) in red algae. Especially, that of Iron in green algae showed higher value than in any other. 7) The content of Manganese were in the range of 48-221ppm (average: 157.25ppm) in green algae, 12-65ppm (average: 41ppm) in brown algae and 72-162ppm (average: 121ppm) in red algae. Especially, that of Manganese in brown algae showed lower value than in any other. 8) The content of Zinc were in the range of 191.3-451.1ppm (average: 290.05ppm) in green algae, 89.9-374.2ppm (average: 202.64ppm) in brown algae and 106.4-281.4ppm (average: 188.93ppm) in red algae. 9) The content of Magnesium were in the range of 0.48-1.83% (average: 1.27%) in green algae, 1.04-1.71% (average: 1.21%) in brown algae and 0.42-1.24% (average: 0.097%) in red algae. 10) The content of Fluorine were in the range of 29.2-92.7ppm (average: 53.03ppm) in green algae, 33.3-43.5ppm (average: 39.18ppm) in brown algae and 32.4-59.0ppm (average: 44.84ppm) in red algae.

• Journal of the Mineralogical Society of Korea
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• v.26 no.4
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• pp.229-244
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• 2013

Arsenic contamination may be brought about by a variety of natural and anthropogenic causes. Among diverse naturally-occurring chemical speciations of arsenic, trivalent (As(III), arsenite) and pentavalent (As(V), arsenate) forms have been reported to be the most predominant ones. It has been well known that the behavior of arsenic is chiefly affected by aluminum, iron, and manganese oxides. For this reason, this study was initiated to evaluate the applicability of manganese slag (Mn-slag) containing high level of Mn, Si, and Ca as an efficient sorbent of arsenic. The main properties of Mn-slag as a sorbent were investigated and the sorption of each arsenic species onto Mn-slag was characterized from the aspects of equilibrium as well as kinetics. The specific surface area and point of zero salt effect (PZSE) of Mn-slag were measured to be $4.04m^2/g$ and 7.73, respectively. The results of equilibrium experiments conducted at pH 4, 7 and 10 suggest that the sorbed amount of As(V) was relatively higher than that of As(III), indicating the higher affinity of As(V) onto Mn-slag. As a result of combined effect of pH-dependent chemical speciations of arsenic as well as charge characteristics of Mn-slag surface, the sorption maxima were observed at pH 4 for As(V) and pH 7 for As(III). The sorption of both arsenic species reached equilibrium within 3 h and fitting of the experimental results to various kinetic models shows that the pseudo-second-order and parabolic models are most appropriate to simulate the system of this study.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.937-945
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• 2010

This study aimed to investigate the effects of dietary zinc (Zn), environmental temperatures and Zn${\times}$temperature interaction on growth, feathering score and mineral composition of broilers. A total of 256 d-old Avian male broiler chicks were randomly allocated to a $4{\times}2$ factorial arrangement with four corn-soybean meal basal diets (containing 44 mg Zn/kg) supplemented with 0, 40, 60 mg/kg Zn (Diets 1, 2 and 3, respectively; 0.8% Ca for these three diets) and non-Zn supplementation, 1.6% Ca (Diet 4) and two temperature conditions (low: 26, 24, $22^{\circ}C$ vs. high: 30, 28, $26^{\circ}C$). All birds were given feathering coverage scores for back, breast, wing, under-wing and tail. The wing and tail were further evaluated for the occurrence and severity of defect feathers. Feathers were then pooled for mineral composition analysis. The results showed that in high temperature conditions, broilers fed Zn-unsupplemented, 0.8% Ca ration (Diet 1) had significantly (p<0.05) lower ADFI and ADG (wk 1-6) than birds under low temperature conditions. However, when the birds were fed 40 and 60 mg/kg Zn supplementation (Diets 2 and 3), the ADFI and ADG in both temperature conditions were not significantly different. In low temperature conditions, the ADFI, ADG (p<0.05), all feather coverage (p<0.01) and tail defect scores (p<0.001) of birds fed Diet 4 (excess Ca) were significantly poorer than those fed Diet 1. More Ca (p<0.05) was retained in the feathers of broilers fed Diet 4 under high temperature conditions. Broilers fed the Zn-unsupplemented ration (Diet 1) had significantly higher feather phosphorus (p<0.01) and potassium (p<0.05) concentrations than those fed the 60 mg/kg Zn-supplemented ration (Diet 3). A reduction of feather phosphorus (p<0.01) and potassium (p<0.05) and higher manganese (p<0.05) concentrations were observed in Diet 4 broilers as compared to those fed Diet 1. Under high temperature conditions, broilers had lower iron (p<0.05) and higher manganese (p<0.05) concentrations in feathers. Broilers kept in high temperature conditions had a higher Zn requirement and 40 mg/kg Zn supplementation was sufficient for the birds to achieve optimum growth. Supplemental Zn ameliorated the adverse effect of high temperature on growth and occurrence of tail feather defects. Excess Ca disrupted Zn metabolism to exert a detrimental effect on growth performance and normal feathering and this was elucidated in the birds kept in low temperature conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1631-1634
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• 2011

This study was conducted to estimate the general components, minerals, and dietary fiber contents of Synurus deltoides. S. deltoides contained 81.1% moisture content, and the proportions of crude fat, crude protein, crude ash, and crude fiber were 0.3%, 4.2%, 2.6%, and 3.5%, respectively. Potassium (3,249.1 mg) was the most abundant component among the minerals in S. deltoides. In addition, S. deltoides contained many other minerals, e.g. calcium (854.8 mg), phosphorus (60.3 mg), magnesium (344.7 mg), sodium (57.3 mg), zinc (1.7 mg), iron (30.9 mg), copper (0.8 mg), and manganese (5.8 mg). Almost all of the mineral contents of S. deltoides were higher than those of Aster scaber and Ligularia fischeri, except for zinc, copper, and manganese. Total dietary fiber (TDF), insoluble dietary fiber (IDF), and soluble dietary fiber (SDF) contents of S. deltoides were 42.6 g, 37.9 g, and 4.7 g, respectively, and these were also higher than those of A. scaber and L. fischeri used in this study. These results suggest that S. deltoides may be a valuable nutrient source.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.302-312
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• 2017

Objectives: In this study, an evaluation of the working environment of furnace workers was performed and the work-relatedness of the occupational diseases were examined Methods: In this study, two electric furnaces at a single casting business site producing manganese-based iron alloy were selected, and occupational exposures to hazardous substances were evaluated for furnace workers and furnace worker assistants. Results: As a result, total dust concentration were $0.407{\sim}3.001mg/m^3$ and respirable dust concentration were $0.196{\sim}0.584mg/m^3$. The highest concentration of crystalline silica was $0.079mg/m^3$ In the case of Masato and Sosuckwhoi crystalline silica, they contained 90.85% and 4.17% respectively. Manganese concentration was the highest at a $0.205mg/m^3$ maximum. The average of black carbon is $11.56{\mu}g/m^3$ and the maximum concentration is $604.23{\mu}g/m^3$. PAHs concentration was the highest at a $78.301{\mu}g/m^3$ of naphthalene. The concentration of carbon monoxide was 18.82 ppm(total average 3.89 ppm) during pouring, and the maximum is 131 ppm. The formaldehyde concentration was 0.003 to 0.007 ppm. Conclusions: It seems that conditions in the past were worse, since casting has recently been performed only twice per day for about 20 minutes, reducing the amount of pouring, and local exhaust systems have been installed one-by-one. In addition, it was judged that the past exposure levels were higher considering the points measured on the back-side due to the risk of damage to the individual samples. It was found that operators could be exposed to high concentrations of crystalline silica, and that they were also exposed to high concentrations of metal(fume) and carbon monoxide during pouring. Therefore, there is a risk that occupational diseases such as lung cancer and COPD may occur with long-term work in such a process.

• Resources Recycling
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• v.25 no.1
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• pp.60-67
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• 2016

A scale-up test with a continuous solvent extraction and electro-winning system was carried out to separate and recover copper from a synthetic sulfuric acid solution (Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L). The solution was introduced into mixer-settlers with four stages of extraction and two stages of stripping for continuous countercurrent solvent extraction to separate copper from nickel and cobalt. The loading was carried out using 40% LIX 84-I(v/v) as extractant with a phase ratio of A : O = 1 : 1. Meanwhile, the stripping was undertaken at a phase ratio of A : O = 1 : 1.5 using depleted electrolyte containing 35.0 g/L Cu and 180 g/L $H_2SO_4$ as stripping solution. The extraction and stripping efficiencies were found to be 96.7% and 91.0%, respectively. The copper composition of the stripped solution (pregnant electrolyte) was 50.0 g/L Cu with impurities of 25 ppm nickel, 5 ppm cobalt and 3 ppm iron. In the electro-winning process, copper metal of 99.833 purity was yielded with current efficiency of 98.9% and current density of $1.50A/dm^2$.