• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.521-528
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• 1999

As the size of our industry and population inclose, the byproducts such as municipal solid wastes, industrial wastes are in the increasing phase. The treatment of such things is rising as a social problem. Today, the final disposal of these wastes depends mostly on the landfill, and the sanitary landfill is required and designed for preventing soil and groundwater contamination. Clays have been used for a liner material of a sanitary landfill, however, the high quality clay is hard to come by and quite expensive as a lining material in our country. Using the waste lime produced abundantly every year from chemical processes was studied here, made from the proper mixing of the bentonite and the waste lime meets the regulations from the USEPA. The soil property index tests (sieve analysis, specific gravity test Atterberg limit test) were performed, and at last to confirm the sorption characteristics of the bentonite and the waste lime the sorption isotherm equilibrium test and the sorption isotherm were performed with Toluene and Ethylbenzene which are the main components of the leachate from the landfill.

• Carbon letters
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• v.6 no.3
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• pp.141-147
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• 2005

The carbon sample "O", phosphoric acid-activated carbon "OP", zinc chloride-activated carbon "OZ", and two steam activated carbons "OS" and "OS2" with different burn-off of 25% and 58% respectively, were prepared from olive stones. The textural properties were determined from the results of nitrogen adsorption at 77 K and by analyzing these results through the application of different adsorption models. The chemistry of the carbon surfaces was determined from the base neutralization capacities, acid neutralization capacity and surface pH. The sorption of $Pb^{2+}$ ions on to the carbons prepared was followed under dynamic and equilibrium conditions. The differences between the values of the textural parameters were attributed to the inapplicability of some adsorption models and to the heterogeneity of the microporous carbons. The sorption of $Pb^{2+}$ ions is favored on carbon and activated carbons. However, chemically activated carbons are more effective compared with steam-activated ones. The sorption of $Pb^{2+}$ ions were related to the chemistry of the surface rather than to the textural properties.

• Journal of Ginseng Research
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• v.18 no.3
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• pp.196-199
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• 1994

A study was designed to investigate the sorption characteristics of binary mixture of red ginseng powder and maltodextrin(DE-17) or lactose stored at various relative humidities ranging from 52% to 93%. At low relative humilities below RH 67%, the sorption equilibrium was easily achieved, whereas at higher relative humidity values over 75%, all of the mixtures tended to absorb moisture continuously with an increase in storage time. A linear equation of log(dw/dt): a log(t)+ log b was found to be valid between the sorption rate and storage time with respect to storage humilities. A linearity was also found between log(1-Aw) and the amount of water absorbed over the Aw range of 0.52∼0.93 and the slope was affected by the kind of sugar added with that of red ginseng powder and maltodextrin mixture being the smallest.

• Resources Recycling
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• v.19 no.2
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• pp.28-34
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• 2010

In this study, cow tibial from cow bone, a kind of beef waste, sintered at $800\sim850^{\circ}C$ for three hours was used to measure its removal capacity for metal ions such as Pb, Cd and Zn in a single and a multi-component equilibrium systems. The sorption equilibrium data were analyzed as measured by the effect of media on lead, cadmium and zinc sorption. This analysis shows that the sorption of metal ions for multi-component systems applying IAST can be predicted more reasonably by the Freundlich and the Sips theory than the Langmuir.

• Preventive Nutrition and Food Science
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• v.20 no.3
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• pp.215-220
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• 2015

The moisture sorption isotherms of vacuum-dried edible green alga (Capsosiphon fulvescens) powders were determined at 25, 35, and $45^{\circ}C$ and water activity ($a_w$) in the range of 0.11~0.94. An inversion effect of temperature was found at high water activity (>0.75). Various mathematical models were fitted to the experimental data, and Brunauer, Emmett, and Teller model was found to be the most suitable model describing the relationship between equilibrium moisture content and water activity (<0.45). Henderson model could also provide excellent agreement between the experimental and predicted values despite of the intersection point. Net isosteric heat of adsorption decreased from 15.77 to 9.08 kJ/mol with an increase in equilibrium moisture content from 0.055 to $0.090kg\;H_2O/kg$ solids. The isokinetic temperature ($T_{\beta}$) was 434.79 K, at which all the adsorption reactions took place at the same rate. The enthalpy-entropy compensation suggested that the mechanism of the adsorption process was shown to be enthalpy-driven.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.2
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• pp.116-123
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• 1991

Two solution to soil ratios, 2 : 1 and 5 : 1 were tested to determine the appropriate ratio in the sorption measurement off. sulfoxide for Wahiawa soil samples, 0-20 cm, 40-60 cm and 100-120 cm. and Salinas soil samples, 0-15cm and 115-130cm. One ${\mu}$ mol/L f.sulfoxide was used as an initial equilibration concentration. Sorption of f.sulfoxide at 5 : 1 ratio showed appropriate mixing, while sorption at 2 : 1 ratio indicated insufficient mixing during the various batch equilibration times (4, 12, 24 and 48 hours). For most samples the degree of sorption was about 20-50%, which falls in the desired range (20-80%) at the 5 : 1 ratio. An exception was with the low-sorptive Wahiawa subsoil in which the ranges were below 20%. Thus the 5 : 1 ratio can be used for f.sulfoxide sorption measurement. Four equilibration times (4, 12, 24 and 48 hours) and four concentrations(0.1, 1.0, 5.0 and $10{\mu}mol/L$) were used to determine the appropriate equilibration time for Wahiawa and Salinas soils. Sorption increased over all equilibration times, indicating no complete equilibrium within 48 hours. Apparent equilibrium was reached in 4 hours, and sorption increased slowly until 24 hours and faster thereafter, except for the Wahiawa soil, 100-120 cm. The recommended equilibration time is 24 hours, since it may eliminate the insufficient sorption and yet avoid undesirable transformation.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.3
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• pp.48-54
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• 2009

Resent research on heavy metal biosorption has been focused on its mechanisms and principles. For effective metal removal/recoverythe process design has to be optimized for every type of application. That is most efficiently carried out based on computer simulations by means of mathematical models of the process. Therefore, the study on sorption equilibrium isotherm is important and the methodology wassummarized here involving both one metal and multi-metal systems.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.2
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• pp.253-258
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• 2007

The adsorption capacity of bone char for lead, cadmium and zinc was studied in both single and binary multiple component systems. Equilibrium experimental studies have been performed to determine the sorption capacity of bone char for each metal ion. These have been analysed using single and multi-component equilibrum models. The results show that the sorption of metal ions for multi-component systems can be predicted reasonably well from the IAS theory with the Langmuir equation, the Freundlich and the Slip equation for metal ions.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.986-993
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• 2010

In this study, sorption characteristics of thermally treated activated alumina (AA) for fluoride were investigated. Sorption experiments have been conducted in equilibrium and kinetic batch conditions. Also, effects of solution pH and anions on fluoride removal have been observed. The properties of thermally treated ( $700^{\circ}C$) activated alumina (AA700) and untreated activated alumina (UAA) were compared using field-emission scanning electron microscope, energy-dispersive spectrometry, X-ray diffractometer (XRD) analysis, and Brunauer-Emmett-Teller (BET) analysis. From the experiments using AA thermally treated at different temperatures (100, 300, 500, $700^{\circ}C$), it was found that at high fluoride concentrations (50, 100, 200 mg/L) the sorption capacity of thermally treated AA increased with increasing thermal treatment temperature. At an initial fluoride concentration of 200 mg/L, the sorption capacity of AA700 was 3.67 times greater than that of UAA. The BET analysis showed that the specific surface area of UAA was about 2 times larger than that of AA700. The XRD analysis indicated that UAA was composed of both boehmite (AlOOH) and bayerite ($Al(OH)_3$) while AA700 was $Al_2O_3$. The reason that fluoride sorption capacity of AA700 increased despite of decrease in specific surface area compared to UAA could be attributed to the change of crystal structure. The kinetic sorption test showed that fluoride sorption to AA700 arrived at equilibrium after 24 h. The equilibrium test demonstrated that the maximum sorption capacity of AA700 was 5.70 mg/g. Additional batch experiments indicated that fluoride sorption to AA700 was the highest at pH 7, decreasing at both acidic and basic solution pHs. Also, fluoride sorption to AA700 decreased in the presence of anions such as phosphate, nitrate, and carbonate. This study demonstrated that thermal treatment of AA at high temperature could increase its sorption capacity for fluoride.

• Membrane Journal
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• v.10 no.3
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• pp.139-147
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• 2000

Non-Fickian (or anomalous) diffusion was observed in transient sorption of aromatic solvents(such as benzene, toluene, and chlorobenzene) in fluoropolymers (such as ETFE, ECTFE and PVDF). In this study, five other transient sorption models (Crank, Long ＆ Richman, Berens ＆ Hopfenberg, Neogi, Li) based on Fick's law were employed to fit the anomalous sorption data for aromatic solvents. The adjustable parameters were determined by least square analysis of the measured and predicted fractional uptake. For ETFE sorption data slightly deviating from Fickian behavior, all the models exhibited satisfactory results in fitting the anomalous sorption data. In particular, Neogj model predicted intrinsic diffusivity (0.4～0.8$\times$10$^{-5}$ $\textrm{cm}^2$/day) and equilibrium diffusivity (0.13～0.31$\times$10$^{-4}$ $\textrm{cm}^2$/day) as well as relaxation kinetics related to non-Fickain diffusion. For a typical sigmoidal sorption behavior in PVDF, only Crank's model could give the reasonable evaluation on transport properties. The ratio of intial diffusivity (D$_{i}$) to final equilibrium diffusivity (D$_{\infty}$) was ranged from 80 to 200. For the final stage of uptake In ECTFE with drastic acceleration, all the models exhibited significant deviations from the sorption data. New diffusion models based on thermodynamics and continuum mechanics should be employed to get valuable information on transport properties as well as relaxation kinetics coupled with non-Fickian diffusion.