• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.66-70
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• 2001

In this study farm soil was tested under artificial acid rain(pH = 5.34), which is average pH of Pusan metropolitan area. and to find out the soil's acid neuralization capacity, soil acidity, CEC(cation exchange capacity)and akaline meatals, such as K, Ca and Na were tested. Because oyster shells(OS) had portion of alkaline metals, OS could play a role in acid soil amendment. And soil addition of sewage treatment sludge(STS) could be a alternative for disposal method. The purpose of this study is to evlauate acid soil amendment using STS and OS. In case of soil and STS, mixing ratio was10:0, 9:1, 8:2, 7:3. And STS mixed OS was also added in acid soil as same ratio as STS. Throught the experiment, soil acidity was stationary state with slight decrease, and CEC was also stationary state but with slight increase. Allkaline metals showed differences in concentration, but all of them were tend to decrease. In conclusion, STS mixed OS could play a part in amendment of acid soil.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.70-78
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• 1998

This study was conducted to investigate the adsorption-desorption characteristics of herbicide paraquat on clay minerals, humic materials, and soils under the laboratory conditions. Adsorption time of paraquat on clay minerals was faster than organic materials and soils. Adsorption amount on montmorillonite, 2:1 expanding-lattice clay mineral, was largest among the adsorbents tested. The adsorption capacity of paraquat was approximately 21 % of cation exchange capacity in soils, 45.1 % in kaolinite, and 80.6% in montmorillonite. Humic materials, humic acid and fulvic acid isolated from soil II, adsorbed larger amount of paraquat than kaolinite and soils. Distribution of tightly bound type of paraquat was larger in clay mineral and soils but loosely bound type was larger in humic acid and fulvic acid. In oxidized soil, the adsorption amount of paraquat was decreased to 85.1-95.5% of original soils. Distribution of unbound and loosely bound type of paraquat was decreased in oxidized soil but tightly bound type was increased. The competition cations decreased paraquat adsorption on humic materials and soils but not affected on montmorillonite. No difference was observed as the kinds of cations. In cation-saturated adsorbents, the adsorption amount was decreased largely in humic materials and soils but decreased a little in montmorillonite. The tightly bound type of paraquat in all adsorbents was not desorbed by pH variation, sonication, and cation application but loosely bound type was desorbed. However, the desorption amount was different as a kinds of adsorbents and desorption methods.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.2
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• pp.141-151
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• 2022

The 16 natural zeolites collected from Mongolia (6 types), the United States (1 type), and Korea (9 types) were characterized by XRD, XRF, TGA, DTA, and CEC analysis. All 16 samples are composite minerals. Two or more mineral phases co-exist and consist primarily of minerals such as clinoptilolite, heulandite, mordenite, and chabazite. In certain samples, minerals like illite and quartz were present as impurities. The XRF analysis showed that the 16 natural zeolites contain SiO₂, Al₂O₃, K₂O, CaO, Na₂O, MgO, and Fe₂O₃ oxides. The cation exchange capacity of the U-1 sample was 223.3 meg/100 g, which is higher than the rest of the samples. M-6 sample in Mongolian natural zeolite and K-1 sample in Korean natural zeolite showed the highest cation exchange capacity at 166.6 meg/100 g. As a result of thermal differential and thermos gravimetric analysis, all 16 samples showed excellent thermal stability up to 600℃.

• Journal of Soil and Groundwater Environment
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• v.17 no.2
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• pp.47-53
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• 2012

In this study, the adsorption of $Cu^{2+}$ and $Cd^{2+}$ from aqueous solution on the biochar derived from used coffee grounds at different pyrolysis temperatures has been investigated as a potential low-cost treatment method for heavy metal-containing waters. Three biochar samples prepared by heating coffee sludge at temperature of $300^{\circ}C$ (B300), $500^{\circ}C$ (B500), and $700^{\circ}C$ (B700) were tested for the adsorption capacity and kinetics of Cd and Cu. Also the influencing factor of heavy metal removal by ion exchange in terms of cation exchange capacity (CEC) of each biochar was measured. Adsorption of Ca and Cu by biochar produced at higher pyrolysis temperature showed higher adsorption capacity but the optimal pyrolysis temperature based on performance and economy was known as $500^{\circ}C$. Sorption of Cu and Cd by biochar followed a Langmuir model at pH 6~6.5, attributing mainly to surface sorption. The biochar was more effective in Cu and Cd sorption than activated carbon (AC), with BC 500 being the most effective, which indicates that sorption of Cd and Cu by coffee sludge biochar is partly influenced by chemical sorption on surface functional group as well as physical sorption.

• Journal of Soil and Groundwater Environment
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• v.25 no.1
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• pp.95-105
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• 2020

In this study, iron nanoparticles impregnated hydrochar (FeNPs@HC) was synthesized using lignocellulosic waste and simple one-pot synthetic method. During hydrothermal carbonization (HTC) process, the mixture of lignocellulosic waste and ferric nitrate (0.1~0.5 M) as a precursor of iron nanoparticles was added and heated to 220℃ for 3 h in a teflon sealed autoclave, followed by calcination at 600℃ in N₂ atmosphere for 1 h. For the characterization of the as-prepared materials, X-ray diffraction (XRD), cation exchange capacity (CEC), fourier transform infrared spectrometer (FT-IR), Brunauer-Emmett-Teller (BET), transmission electron microscope (TEM), Energy Dispersive X-ray Spectroscopy (EDS) were used. The change of Fe(III) concentration in the feedstock influenced characteristics of produced FeNPs@HC and removal efficiency towards As(V) and Pb(II). According to the Langmuir isotherm test, maximum As(V) and Pb(II) adsorption capacity of Fe_0.25NPs@HC were found to be 11.81 and 116.28 mg/g respectively. The results of this study suggest that FeNPs@HC can be potentially used as an adsorbent or soil amendment for remediation of groundwater or soil contaminated with arsenic and cation heavy metals.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.296-304
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• 2008

This study was carried out to analyze vegetation and soil characteristic, and ordination of Stewartia koreana community. The Stewartia koreana community was classified into Acer mono subcommunity, Pinus densiflora subcommunity, Sapium japonicum subcommunity, and Stewartia koreana typical subcommunity. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable K, exchangeable Ca, exchangeable Mg concentration, cation exchange capacity, and soil pH were ranged from 14.31~34.27%, 0.33~0.77%, 7.83~22.88(mg/kg), 0.23~1.07(me/100 g), 0.29~2.93(me/100 g), 0.33~1.49(me/100 g), 10.47~22.48(me/100 g), and 4.65~4.96, respectively. The area of the Acer mono subcommunity, found in highlands, showed that contained the highest organic substances, nitrogen, available phosphorous, and cation exchangeable capacity concentration among the communities. The low elevation regions where the Pinus densiflor subcommunity is formed, showed the lowest concentrations of exchangeable Ca, and Mg.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.4
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• pp.239-246
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• 2008

This research tried to find out the optimum fabrication method of calcined clay granules comprising zeolite. Kaolin clay and natural zeolite powder were used as raw materials of calcined clay, and silica stone powder was used for controlling the porosity of the granules. The granulation was performed with two kinds of granulators: a pan granulator and a high-shear mixer granulator. Various granules were fabricated by the mixing ratios and the rotation speeds of the granulators, and were heated from 400 to $700^{\circ}C$ at $100^{\circ}C$ interval. The crushing strength, pore size distribution, and CEC of the granules were measured. The evaluation method for the resistance of granules to human treading was created and the tests were conducted at dry and wet conditions. The resistance and crushing strength improved in proportion to the rotation speed of the granulator and the heating temperature, but the CEC decreased. The pellet made by the pan granulator did not have the strength against treading upon heating to below $700^{\circ}C$, but the pellet made by the high-shear mixer granulator endured the treading test upon heating to over $500^{\circ}C$

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.782-788
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• 2010

Detail management standard on soil conditions in 'Kyoho' grapes were not yet made. Therefore, this study was carried out to investigate the optimum soil environmental conditions on production of high fruit quality in 'Kyoho' grapes. We established using correlation between fruit quality and soil condition. These results were used to develop soil management guideline with promoting efficiency and minuteness in grape vineyard. Soil conditions were analyzed at total 80 vineyards in major grape producing areas such as Ansung, and Cheonan (40 orchards an area). The soil environmental factors affected fruit weight were soil pH of 36.6%, cultivation layer depth of 23.3%, and cation of 17.8%. The soil condition factors affected sugar content were soil hardness of 24.4%, cation of 24.1% and organic matter content of 22.1%. Cultivation layer depth, soil texture, and phosphate content were low as relative contribution. Coloring was involved with organic matter content, CEC (cation exchange capacity), and saturated hydraulic conductivity. while soil pH, cultivation layer depth, and phosphate content showed low contribution. Finally, relative contribution on fruit quality related with sugar content, fruit weight, and coloring were soil hardness of 28.0%, organic matter content of 25.0%, soil pH of 12.9%.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.217-222
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• 2010

Bark is a general medium for potted Cymbidium in Korea, but it is difficult to shake off or eliminate the medium from the roots before exporting the potted plants. This working process can injure the roots and then deteriorate plant marketability. This study was carried out to select the optimum medium easier to eliminate from the roots instead of bark and the optimum amount of applied fertilizer to improve the plant growth. Cymbidium young plants 'Honey Hot' and 'Desert Look' were planted in pots with bark, cocochip, and peatmoss. The plants were treated with 2, 4, and 6 g of slow release fertilizer. The plant growth characteristics were investigated in the first and second years during production period of three years. The medium characteristics and mineral nutrient content of the leaves were also examined in the second year. In the first year, the plant growth of 'Desert Look' was improved in all peatmoss treatments more than bark. 'Honey Hot' showed the highest plant growth values in the bark treatment. In the second year, the plant growth of the two cultivars was improved in peatmoss. Cocochip treatments showed the lower plant growth values than bark and peatmoss in the first and second year. There was no significant difference among fertilizer amounts in all the media. The higher CEC values of peatmoss medium resulted to higher capacity to hold more nutrients than bark, and the nutrient retention of the peatmoss improved the plant growth. The higher K and Ca contents in the leaves would contribute to improve the plant growth. Consequently, it would be possible to use peatmoss instead of bark for Cymbidium young plants, but there must be always attention to appropriately water the medium and manage the moisture.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.371-374
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• 1984

This study was conducted to establish the statistic model by use the soil physico-chemical properties for prediction of ginseng root yield. Twenty seven farmer's red ginseng fields from the ginseng growing area were chosen for this study. Root yield of 6-year old ginseng was $1.85{\pm}0.54Kg$ per $3.3m^2$, and it showed positive correlation between yield and porosity, content of clay, clay and silt, organic matter, cation exchange capacity of the field soils, respectively, but showed a negative correlation with available phosphate. Prediction of root yield was possible with equation combined with porosity($X_1$), content of clay($X_2$), clay and silt($X_3$), available phosphate($X_4$), CEC($X_5$), the equation is $Y=-1.175+0.033X_1-0.04X_2+0.012X_3-0.001X_4+0.171X_5$. Standard partial regression coefficients were 0.3799 in CEC, 0.1550 in content of clay, 0.0890 in porosity, 0.0599 in content of clay silt, and -0.0138 in available phosphate.