• Korean Journal of Environmental Agriculture
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• v.26 no.2
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• pp.124-130
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• 2007

Excess application of paper mill sludge (PMS) in field can limit phosphorus uptake by crops because aluminum presented in the sludge can fix or adsorb available phosphorus which is necessary for crop growth. To investigate phosphorus (P) adsorption characteristics of PMS, we examined P adsorption maximum $(X_m)$ using Langmuir isotherm and P adsorption energy constant $(K_f)$ using Freundlich isotherm for PMS without alum, PMS with alum, and composted PMS with alum through a laboratory incubation test. The maximum P adsorption capacities were 800 ${\mu}g\;g^{-1}$ in soil, 47 $mg\;g^{-1}$ in PMS without alum and 61 $mg\;g^{-1}$ in PMS with alum. P adsorption capacity with alum treatment for PMS increased by 30%. That of PMS compost was 68 $mg\;g^{-1}$ and showed that composting increases 11% of P adsorption. Freundlich constant $K_f$ was 22 in check soil, while $K_f$ values in PMS without alum and in PMS with alum were 398 and 426, respectively. After composting, $K_f$ value of PMS compost significantly increased as 1,819. In conclusions, p adsorption capacity for PMS were increased by alum treatment or composting and therefore excess or continuous land application of alum-amended or composted PMS can limit P uptake for crops by reducing available P in sell.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1323-1328
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• 2006

Mesoporous nickel intercalated aluminosilicate nanohybrid has been synthesized through a recombination reaction between the colloidal suspension of exfoliated montmorillonite nanosheets and aqueous nickel acetate solution. According to powder X-ray diffraction and field emission-scanning electron microscopic analyses, the intercalation of nickel species expands significantly the basal spacing of the host montmorillonite clay and the crystallites of the intercalation compound are assembled to form a house-of-card structure. $N_2$ adsorption-desorption isotherm measurements with BJH pore analyses clearly demonstrated that the porosity of the intercalate originates mainly from mesopores (diameter $\sim50\;\AA$) formed by the house-of-card type stacking of clay crystallites. From FT-IR and X-ray absorption spectroscopic analyses, it becomes certain that intercalated nickel ion is stabilized in an isolated $NiO_6$ octahedral unit. The present mesoporous intercalation compound is expected to be applicable as efficient catalysts or absorbents.

• Journal of Environmental Science International
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• v.15 no.2
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• pp.133-139
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• 2006

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and NOx compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study was performed to evaluate effect of removal of gaseous NOx using a soil and a yellow soil. Over $60\%\;and\;48\%$ of NOx from a soil and a yellow soil was removed at the inlet NO concentrations of $423\~451$ppb, respectively. The bio-filter using a soil media was capable of purifying NOx with a different natural processes. Although some of the processes are quite complex, they can broadly be summarized as adsorption into soil pore water, and biochemical transformations by soil bacteria. When the filteration bio-reactor was applied to a soil and a yellow soil, effective NOx removal was obtained for several times and months. These results show that a soil biofilter can be of use as an alternative advanced NOx treatment system.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.357-366
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• 2022

Biochar can be obtained by using various types of biomass under an oxygen-limited condition. Biochar can be utilized for various applications such as soil improvement, waste management, growth promotion, and adsorption. Wood vinegar is produced by the process of pyrolysis wood biomass and is used as a growth promoter, for soil improvement, and as a feed additive. When wood vinegar is treated on soil, it acts to control soil pH, improve nutrient availability, and alleviate N₂O and NH₃ volatilization. The objective of this study was to evaluate the effect of biochar and wood vinegar on the growth of perilla and soil quality. The experiment was conducted by using a Wagner pot (1·5,000 a^-1) in a glass greenhouse. The biochar was produced by pyrolysis at 450℃ for 30 minutes using rice husk and rice straw. Wood vinegar was diluted to 1 : 500 (v·v^-1) and used in this experiement. In the results of a cultivation experiment, co-application of biochar and wood vinegar enhanced the growth of perilla. In particular, rice husk biochar affected the leaves of the perilla, and rice straw biochar influenced the stems of the perilla. In addition, soil quality after treatment with biochar and wood vinegar applied together was highest compared to other units. Therefore, it is anticipated that co-application of biochar and wood vinegar will be more productive and improve soil quality compared to individual utilization of biochar and wood vinegar.

• Resources Recycling
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• v.31 no.4
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• pp.56-65
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• 2022

Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.3
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• pp.175-179
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• 2015

In this study, we propose Ti hole pattern structure on the transparent conductive oxide (TCO) less dye-sensitized solar cells (DSSCs) using the lift-off process to improve the low light transmittance and low efficiency caused by opaque Ti electrode. The formation of Ti hole patterns make it possible to move the dye adsorption and electrolyte. The DSSCs with Ti hole patterns showed a higher photoelectric conversion efficiency (PCE) than those with general structure by 11.1%. As a result, The Ti hole pattern structure can be improved to increase the light absorption of the dyes and PCE of the TCO-less DSSCs is also increased.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.402-406
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• 2006

The physical and chemical characteristics of ALC were analyzed and showed 2.2 of specific gravity and 9.05 of pH. The results of leaching tests with standard method for soil and waste indicated heavy metals(Cu, Cd, Pb, $Cr^{6+}$) were under maximum concentration level. The anaerobic digestion sludge was attached in the surface of ALC within 90 hours. As the results of batch test, pH of the ALC and Bio-ALC were decreased from initial pH of ALC to 8.7 and 7.8 respectively Also, the concentration of heavy metals was rapidly eliminated in the solution with the batch test. The result of column experiment indicates that the removal efficiency of ALC was showed 66% of T-P, 60% of T-N, and 67% of CODcr. Also, removal efficiency of Bio-ALC was slightly higher than that of ALC in T-N (64%) and CODcr (74%).

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.573-581
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• 2007

The present study deals with removal of $CO_2$ using various mesoporous materials impregnated with MEA (monoethanolamine). The mesoporous materials such as MCM-41, MCM-48 and SBA-15 were synthesised and then impregnated with 30, 50 and 70 wt% of MEA, respectively. XRD, FT-IR and SEM were used to evaluate the characterization of those. From the adsorption/desorption experiments for various materials, the adsorption capacity of these materials were found in the order of MCM-41> MCM-48> SBA-15. MCM-41 impregnated with 50 wt% of MEA showed the maximum adsorption capacity of $57.1mg-CO_2/gr-sorbent$ at $40^{\circ}C$. It is nearly 8 times higher than MCM-41 without impregnation of MEA. In the multiple cycle test of 20 times, MCM-41 impregnated with 50 wt% of MEA showed a constant adsorption capacity.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.155-160
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• 2015

BACKGROUND: Objective of this study was to investigate adsorption characteristics of $NH_4-N$ to biochar produced from rice hull in respective to mitigation of greenhouse gases. METHODS AND RESULTS: $NH_4-N$ concentration was analyzed by UV spectrophotometer. For adsorption experiment of $NH_4-N$ to biochar, input amount of biochar was varied from 0.4 to 10 g/L with 30 mg/L $NH_4-N$ solution. Its adsorption characteristic was investigated with application of Langmuir isotherm. Adsorption amount and removal rates of $NH_4-N$ were decreased at 53.9% and increased at 20.2% with 10 g/L compared to 0.4 g/L, respectively. The sorption of $NH_4-N$ to biochar produced from rice hull was fitted well by a Langmuir model. The largest adsorption amount of $NH_4-N$ ($q_m$) and binding strength constant (b) were calculated as 0.4980 mg/g, and 0.0249 L/mg, respectively. It was observed that dimensionless constant ($R_L$) was 0.58. CONCLUSION: It was indicated that biochar produced from rice hull is favorably absorbed $NH_4-N$, because this value lie within 0< $R_L$ <1.

• Resources Recycling
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• v.13 no.4
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• pp.23-31
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• 2004

Basic studies have been conducted regarding the attempt of the utilization of waste Undaria pinnatifida as an adsorbent for the adsorption treatment of lead-containing wastewater. Undaria pinnatifida was found to be chiefly composed of hyo-carbonaceous compounds and have a fairly high specific surface area, which suggesting the possibility of its application as a Potential adsorbent. The electrokinetic Potential of Undaria pinnatifida particles was observed to be negatively highest at around pH 8 and the fact that its electrokinetic potentials are negative at the whole pH range supported it might be an efficient adsorbent especially for cationic adsorbates. Under the experimental conditions, $Pb^{2+}$ was found to mostly adsorb onto Undaria pinnatifida within a few minutes and reach the equilibrium in adsorption within ca. 30 minutes. The adsorption of $Pb^{2+}$ was exothermic and explained well by e Freundlich model. Acidic pretreatment of Undaria pinnatifida enhanced its adsorption capacity for $Pb^{2+}$ , however, the reverse was observed for alkaline pretreatment. The formation of organometallic complex between $Pb^{2+}$ and some functional groups on the surface of Undaria pinnatifida was considered to be one of the main drives for adsorption. Finally the adsorbability of$ Pb^{2+}$ was examined to be rather affected by several solution features such as the coexistence of other adsorbate, the variation of ionic strength, and the concentration of complexing agent.