• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.63-70
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• 2006

Biosorption characteristics were investigated at various temperature and pH conditions in order to establish lead(II) removal using Zoogloea ramigera 115SLR. Biosorption equilibrium isotherms and kinetics were obtained from batch experiments. The Freundlich and Langmuir model could be described the biosorption equilibrium of lead(II) on Z. ramigera 115SLR, Ca-alginate bead and immobilized Z. ramigera 115SLR. The maximum biosorption capacity of Z. ramigera 115SLR increased from 325 to 617mg $pb^{2+}/g$ biomass as temperature increased from 288.15 K to 308.15K from the Langmuir model. Fixed-bed column breakthrough curves for lead(II) removal were also obtained. For regeneration of the biosorbent, complete lead(II) desorption was achieved using 5mM HCl in fixed-bed column. This study shows the possibilities that well-treated immobilized Z. ramigera 115SLR with the mechanical intensity like TEOS (Tetraethyl orthosilicate) treatment and the optimum acid solution for desorption can be used for the effective treatment for lead(II) containing wastewater.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.3017-3026
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• 2022

The ¹³¹Cs radioisotope with a short half-life time and high average radiation energy can treat the cancer effectively in prostate brachytherapy. The typical ¹³¹Cs production processes have a separation step of the cesium from ¹³¹Ba to obtain a high specific radioactivity. Herein, we suggested a novel ¹³¹Cs separation method based on the Ba²⁺ adsorption of alginate beads. It is necessary to reduce the affinity of alginate beads to cesium ions for a high production yield. The carboxyl group of the alginate beads was replaced by a sulfonate group to reduce the cesium affinity while reinforcing their affinity to barium ions. The modified beads exhibited superior Ba²⁺ adsorption performances to native beads. In the fixed-bed column tests, the saturation time and adsorption capacity could be estimated with the Yoon-Nelson model in various injection flow rates and initial concentrations. In terms of the Cs elution, the modified alginate showed better performance (i.e., an elution over 88%) than the native alginate (i.e., an elution below 10%), indicating that the functional group modification was effective in reducing the affinity to cesium ions. Therefore, the separation of cesium from the barium using the modified alginate is expected to be an additional option to produce ¹³¹Cs.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.61-69
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• 2005

Adsorption characteristics of toluene vapor, which is one of important source of volatile organic compounds (VOCs), by activated carbon were investigated using a fixed bed adsorption column. The operating parameters such as breakthrough curve, adsorption capacity, mass transfer zone (MTZ), and length of unused bed (LUB) were studied. The experimental results showed that the breakthrough time decreased with increasing inlet toluene concentration and gas flow rate. MTZ and LUB increased with the increase of inlet concentration, gas flow rate, and particle size of activated carbon. The adsorption capacity increased with the increase of inlet toluene concentration, while it decreased with increasing particle size. However, it was kept at constant value regardless of the increase of gas flow rate. Adsorption isotherm of toluene vapor could be represented by the Freundlich adsorption equation fairly well. From the adsorption experiments using some VOC gases such as toluene, xylene, butyl acetate. butanol and acetone, it was also found that the adsorption capacity was higher in the case of gas with higher boiling point and lower vapor pressure.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.568-572
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• 2009

The adsorption characteristics of tartrazine by granular activated carbon were experimentaly investigated in the batch adsorber and the packed column. The adsorptivity of activated carbon for tartrazine was largely improved by pH control, and 98 percent of initial concentration could be removed at pH 3. It was estabilished that the adsorption equilibrium of tartrazine on granular activated carbon was sucessfully fitted by Freundlich isotherm equation in the concentration range from 50 mg/L to 1,000 mg/L. The characteristics of breakthrough curve of activated carbon packed column, which depend on the design variables such as initial concentration, bed height, and flow rate, were studied.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.34-39
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• 2009

The adsorption characteristics of amatanth by granular activated carbon were experimently investigated in the batch adsorber and the packed column. The adsorptivity of activated carbon for amaranth were largely improved by pH control, and 94 percent of initial concentration(100mg/L) could be removed at pH 9. It was estabilished that the adsorption equilibrium of amaranth on granular activated carbon was sucessfully fitted by Freundlich isotherm equation in the concentration range from 1mg/L to 100mg/L. The characteristics of breakthrough curve of activated carbon packed column, which depend on the design variables such as initial concentration, bed height, and flow rate, were studied.

• Advances in environmental research
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• v.3 no.3
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• pp.231-251
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• 2014

The present study examines the phosphate adsorption potential and behavior of mixture of Ground Burnt Patties (GBP), a solid waste generated from cooking fuel used in earthen stoves and Red Soil (RS), a natural substance in fixed bed column mode operation. The characterization of adsorbent was done by Proton Induced X-ray Emission (PIXE), and Proton Induced ${\gamma}$-ray Emission (PIGE) methods. The FTIR spectroscopy of spent adsorbent reveals the presence of absorbance peak at $1127cm^{-1}$ which appears due to P = O stretching, thus confirming phosphate adsorption. The effects of bed height (10, 15 and 20 cm), flow rate (2.5, 5 and 7.5 mL/min) and initial phosphate concentration (5 and 15 mg/L) on breakthrough curves were explored. Both the breakthrough and exhaustion time increased with increase in bed depth, decrease in flow rate and influent concentration. Thomas model, Yoon-Nelson model and Modified Dose Response model were used to fit the column adsorption data using nonlinear regression analysis while Bed Depth Service Time model followed linear regression analysis under different experimental condition to evaluate model parameters that are useful in scale up of the process. The values of correlation coefficient ($R^2$) and the Sum of Square Error (SSE) revealed the Modified Dose Response model as the best fitted model to the experimental data. The adsorbent mixture responded effectively to the desorption and reusability experiment. The results of this finding advocated that mixture of GBP and RS can be used as a low cost, highly efficient adsorbent for phosphate removal from aqueous solution.

• Environmental Engineering Research
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• v.24 no.1
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• pp.31-37
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• 2019

In this paper the results of the biosorption of lead(II) and cadmium(II) with sugarcane bagasse in fixed bed columns are presented. Experimental data were fitted to several models describing the rupture curve for single-component and two-component systems. The percentages of removal of lead and cadmium in single-component systems are 91% and 90%, respectively. In lead-cadmium bicomponent systems the percentage of elimination of lead was 90% and cadmium 92%. In single-component systems, Yoon-Nelson and Thomas models successfully reproduce the rupture curves. In two-component system, the Dose-Response model was the best one reproducing the experimental rupture curves in the entire measured range.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.2
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• pp.87-95
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• 1983

Trihalomethane removal efficiency by a fixed bed carbon adsorber was a subject of this study. Along with laboratory scale column operations, a simple adsorption model was developed to predict removal efficiency. The adsorption model includes an overall mass transfer coefficient, K and Freundlich adsorption constants, $K_F$ and n. Simulation results showed that increasing K and $K_F$ or decreasing n would take more loading and prolong run time of the adsorption bed. Typical S-shaped breakthrough curves were obtained from the experiments. The operational results at $20^{\circ}C$ and $25^{\circ}C$ indicated that a moderate difference in water temperature would not affect the treatment efficiency significantly. The adsorption constants determined from the column operation and the model simulation were reasonably close to those obtained from the isotherm test. It may be concluded that trihalomethane can be removed successfully by a fixed bed carbon adsorber.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.718-722
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• 2012

$H_2S$ adsorption characteristics of adsorbent made by sewage sludge were investigated. For analyses of the manufactured adsorbent, various methods such as Iodine adsorptivity, scanning electron microscope (SEM), and measurements of BET surface area and pore volume were adopted. As the major adsorption characteristic, breakthrough curve was measured by using a continuous fixed bed adsorption column for operating variables such as adsorption temperature ($25{\sim}45^{\circ}C$), aspect ratio (L/D)(3~9), gas flow rate (0.1~2.0 liter/min) and $H_2S$ gas concentration (50~200 ppm). The experimental result showed that the carbonization and activation of sewage sludge are very important for the improvement in $H_2S$ adsorption capacity.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.454-462
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• 2011

A study on the adsorption characteristics of Pb(II) and Cr(III) cations onto C-methylcalix[4]resorcinarene (CMCR) has been conducted. CMCR was produced by one step synthesis from resorcinol, acetaldehyde, and HCl. Most parameters in batch system confirm that CMCR is a good adsorbent for Pb(II) and Cr(III). Cr(III) uptake was bigger than that of Pb(II), but Cr(III) adsorption rate was slower than Pb(II). The adsorption kinetic of Pb(II) and Cr(III) adsorptions in batch followed pseudo $2^{nd}$ order kinetics model, but the kinetic of Pb(II) adsorption in fixed bed column system followed first order model. Desorption studies to recover the adsorbed Pb(II) was performed sequentially with distilled water and HCl, and the results showed that the adsorption was dominated by chemisorption.