• KSBB Journal
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• v.14 no.3
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• pp.279-283
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• 1999

We have compared the breakthrough behavior of lysozyme contained in fresh han egg white on various cation exchagers, and the adsorbent, known by the trade name Cellufine C-200 (Amicon), has shown the best performance. The effects of ion strength, pH, and linear flow rate on the breakthrough behavior were examined using the Cellufine C-200 adsorbent. The optimal conductivity, pH and linear flow rate were determined from the breakthrough behavior and found to be 2.75 mS/cm, 7.0, and 0.635 cm/min, respectively.

• Journal of the Korean Applied Science and Technology
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• v.17 no.2
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• pp.83-88
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• 2000

The VOCs(Volatile Organic Compounds) is one of the major cause for the atmosphere pollution. Breakthrough behavior of benzene and toluene in adsorption bed packed with activated carbon was experimentally studied. Composition and temperature of the gas flowing in the bed was measured and breakthrough curves for each component was obtained. Breakthrough time of benzene was earlier than that of toluene due to relatively weak adsorptivity. The relationship between breakthrough time and flow rate was obtained. The shape of temperature change with time was dependent on the position in the bed. Temperature changed faster and sharper in the inlet than in the outlet. It was noted that breakthrough behavior could be affected by the heat transfer properties.

• Environmental Engineering Research
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• v.25 no.1
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• pp.104-113
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• 2020

Adsorptive breakthrough modelling is essential for design of a sorption packed bed. In this work, breakthrough modelling of the furfural uptake in bagasse fly ash (BFA) packed bed has been performed. Effect of various parameters like bed height (Z = 15-60 cm), flow rate (Q = 0.02-0.04 L/min) and initial furfural concentration (C_o = 50-200 mg/L) on the breakthrough curve of furfural sorption in a BFA packed bed have been studied. Enhanced breakthrough performance was observed for the higher value of Z, and lower values of C_o and Q. For C_o = 100 mg/L, packed bed operated at Q = 0.03 L/min and Z = 60 cm was found to have lowest adsorbent utilization rate of 5.61 g/L with highest breakthrough volume of 14.67 L. Bed depth service time and Thomas models well represented the experimental data points under all experimental conditions. It can be concluded that BFA can be utilized efficiently in continuous system for the removal of furfural. Overall, more than 99% of furfural was adsorbed in BFA packed bed at experimental conditions.

• Advances in environmental research
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• v.7 no.1
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• pp.29-37
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• 2018

A simple mathematical model for predicting fixed bed adsorption dynamics is described. The model is characterized by a linear adsorption isotherm and a linear driving force expression for mass transfer. Its analytic solution can be approximated with an algebraic equation in closed form which is easily evaluated by spreadsheet computation. To demonstrate one application of the fixed bed model, a previously published adsorption system is used as a case study in this work. The adsorption system examined here describes chromium breakthrough in a fixed bed adsorber packed with imidazole functionalized adsorbent particles and is characterized by a nonlinear adsorption isotherm. However, the equilibrium behavior of the fixed bed adsorber is in essence governed by a linear adsorption isotherm due to the use of a low influent chromium concentration. It is shown that chromium breakthrough is predicted reasonably well by the fixed bed model. The model's parameters can be easily extracted from independent batch experiments. The proposed modeling approach is very simple and rapid, and only Excel is used for computation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.236-239
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• 1998

This research was performed to check the transport characteristics of heavy metals in contaminated soil, that is, the influence of humic acid and phosphate on transport characteristics of heavy metals was studied. From the results of column mode experiments about heavy metal behavior, the order time to reach breakthrough and equilibrium was soil ＋ humic acid( 20g ) > soil ＋ humic acid ( 5 g ) > soil without Humic acid addition > soil+humic acid( 50g ). It is because the dissolved organic carbon content increased as the soil organic matter content increased. As the phosphate increased, so did the time to reach breakthrough and equilibrium. The order of time was soil + phosphate( 50 mg ) > soil + phosphate( 20 mg ) > soil . phosphate( 10 mg ) > soil without phosphate addition. It is because the phosphate ion worked as alkalinity donor and the calcium ion co-injected worked as the accelerator of coprecipitation of heavy metals.

• Journal of Soil and Groundwater Environment
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• v.6 no.2
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• pp.3-13
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• 2001

It has been known that nonlinear characteristics of sorption affect the transport behavior of water soluble pollutants in soils. However detailed experimental studies have not been performed to verify the effect of non-linearity of adsorption isotherm on transport of chemicals in porous media. In this research, the distortion of breakthrough curves of a cationic surfactant (cetylpyridinium chloride, CPC) in a engineered stainless steel column packed with glass beads were investigated. Glass beads with about 110 $\mu\textrm{m}$diameter coated with a thin n-decane film were used as the media providing the sorption surface for CPC. The CPC adsorption isotherm on the surface of n-decane from aqueous solution was a typical Langmuir type. The breakthrough curve of CPC using step Input showed a late breakthrough on the front side and early breakthrough on the back side accordance to the shape of the isotherm. The retardation factor of CPC was found to be a strong function of the input concentration, which also a manifestation of the non-linearity of the isotherm. The retardation factors for the CPC with step input agreed with those of pulse input that the maximum concentrations are controlled to be the same as the step input concentrations. This results support the validity of the unproven field practices of using hydrogeotracers with non-linear adsorption isotherms to determine the hydrogeological parameters, e.g., NAPL saturation, air-water or NAPL-water interfacial areas.

• The Journal of Korea Robotics Society
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• v.17 no.1
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• pp.86-92
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• 2022

Utilization of small robots in psychology and biology provides a new breakthrough in understanding the neurobiological mechanisms of various animal behavior. The expansion of robot use in animal research is partly due to increased availability of economically plausible mobile robots and also due to the current shift in animal research toward more ecologically valid experiments. Ground-breaking experimental findings are expected when the behavioral variables are manipulated in more natural situations. In addition, the results from laboratory could be generalized more easily with added ecological validity. The current paper attempts to review a wide range of applications of animal robots used to study animal behavior and to highlight major advantages and limitations. In particular, this review focuses more on the psychological impact of animal robots than engineering details about their structure and operation. Finally, this review will provide some practical considerations when employing robots in animal experiments.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.166-172
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• 1999

Fixed-bed adsorption of metal ions on chitosan bead was studied to remove heavy metal ions in waste water. Chitin was extracted from carb shell and chitosan was prepared by deacetylation of the chitin. The chitosan in bead was used as an adsorbent for heavy metal ions. Freundlich and Langmuir isotherm was determined from the experimental results of equilibrium adsorption for individual metal ion ($Cu^{2+}$, $Co^{2+}$, $Ni^{2+}$) on chitosan bead. Adsorption strength of metal ions decreased in the order of $Cu^{2+}$>$Co^{2+}$>$Ni^{2+}$ ion. Breakthrough curves of single and multicomponent adsorption for metal ions were obtained from the experimental results of fixed-bed adsorption. The breakthrough curves were analyzed by simulation with fixed-bed adsorption equation based on LDFA (linear driving force approximation) adopted LAS (ideal adsorbed solution) theory which can predict multi-component adsorption isotherm from individual adsorption isotherm. The behavior of fixed bed adsorption for single and multi-component system could be nicely simulated by the equation.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.60-69
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• 2007

Understanding the behavior of gas phase VOCs (volatile organic compounds) in unsaturated soils is of a great environmental importance for public health concerns. Moment analysis for the breakthrough curves (BTCs) during transport of chemicals in porous media was known to be a useful tool to evaluate the velocity, spreadness, and the skewness of the plume of the chemicals. In this study, the temporal moments of the BTCs of a group of VOCs were analyzed for the gaseous transport in an unsaturated soil. BTCs were measured using lab-scale column experiments for four different VOCs at the water saturation range of 0.04-0.46, and for eleven VOCs at a water saturation of 0.21. The central second and third moments of the VOCs were compared with the water saturation and the first moment. It was found that both central second and third moments increased with the first moment. The central third moment was, however, found to be more sensitive to the first moment.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1067-1072
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• 2002

A new polystyrene-divinylbenzene resin containing 2-(2-thiazolylazo)-5-dimethylamino-phenol (TAM) functional groups has been synthesized and its sorption behavior for nineteen metal ions, including Zr(Ⅳ),Hf(Ⅳ) and U(Ⅵ) has been investigated by batch and column methods. The chelating resin showed high sorption affinity for Zr(Ⅳ) at pH 1-5 and U(Ⅵ) at pH 4. Some parameters affecting the sorption of the metal ions have been detailed. The breakthrough and overall capacities were measured under optimized conditions. The overall capacities of Zr(Ⅳ), Th(Ⅳ) and U(Ⅵ), which showed higher than the other metal ions, were 0.90,0.84 and 0.80 mmol/g, respectively. The elution order of metal ions at pH 4 was evaluated as Zr(Ⅳ) > Th(Ⅳ) > U(Ⅵ) > Cu(Ⅱ) > Hf(Ⅳ) > W(Ⅵ) > Mo(Ⅵ) > In(Ⅲ) > Sn(Ⅳ) > Cr(Ⅲ) > V(Ⅴ) > Fe(Ⅲ). Quantitative recovery of most metal ions except Zr(Ⅳ) was achieved using 2M HNO3. Desorption and recovery of Zr(Ⅳ) was successfully performed with 2 M HClO4 and 2 M HCl.