• Clean Technology
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• v.7 no.2
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• pp.133-140
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• 2001

The adsorption characteristics of binary-component Volatile Organic Compounds(VOCs) with benzene and toluene were studied in a fixed bed backed with activated carbon. The adsorption intensites of benzene and toluene resulted from equilibrium adsorption capacity led to roll up phenomenon in a fixed bed and behaved benzene as non-key component which meant the smaller affinity to the activated carbon of the two. From comparion with breakthrough curves between binary-component and single component systems at the same concentration conditions, the stoichiomertic breakthrough time of toluene in both systems had no difference, but that of benzene as non-key component had a tendency to shorten 130min than 200min of single component. In the breakthrough characteristics of binary-component adsorbates, the magnitude of roll-up of the non-key component increased with the increasing of non-key component ratio and aspect ratio(L/D) of fixed bed, while decreased with the increasing of interstitial velocity. Especially, the roll-up phenomenon was more conspicuous with the increasing of mole fraction of key component.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.E
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• pp.19-25
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• 1998

Adsorption characteristics of DMMP and IMPF were investigated using dynamic adsorption method. Adsorbate vapor was forced to Pass at fixed flow rate of 4 mg/I through Cu Cr impregnated activated carbon column at several different flow velocities until the effluent concentrations exceeded 4.0$\times$10$^{-5}$ mg/I. The kinetic adsorption capacity, adsorption kinetic constant, and critical bed weight of the activated carbon were determined for DMMP and IMPF vapors by plotting breakthrough time as a function of carbon weight. A mathematical expression was deduced from our experimental data to represent the relationships between kinetic adsorption capacity and flow velocity. According to our experimental results, the lifetime of DMMP was longer than that of IMPF under the same conditions. Their relationship can be expressed empirically as follows: Tb(DMMP) ＝ 0.9825$\times$Tb(IMPF)-15.368

• Clean Technology
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• v.20 no.2
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• pp.166-170
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• 2014

The continuous experiments were carried out using fixed-bed column packed with strong-acid cation exchange resin for the removal of lithium ions from aqueous solution. The parameters such as bed height, flow rate and inlet concentration were investigated. Breakthrough time ($t_{0.05}$), saturation time ($t_{0.95}$), and total amount of lithium ion removed (mtotal) were obtained from the breakthrough curves. The results showed that $t_{0.05}$ and $t_{0.95}$ decreased with decreasing bed height, and decreased with increasing inlet concentration and flow rate. mtotal increased with increasing inlet concentration and bed height, but decreased with increasing flow rate. Thomas model and Yoon-Nelson model equations were applied to the experimental data, the results showed that the breakthrough data gave a good fit to Thomas model equation.

• Journal of Soil and Groundwater Environment
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• v.11 no.1
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• pp.14-22
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• 2006

Laboratory column experiment for simultaneous removal of Cd and Cr(VI) were conducted using newly developed material of Fe-loaded zeolite having both reduction ability and sorption capacity. The solution containing Cd and Cr(VI) was injected into the column and the breakthrough curves (BTCs) for the contaminants were observed at the effluent port. Cd breakthrough was not initialized until Cr(VI) breakthrough was completed. Therefore it could be concluded that overall efficiency of Fe-loaded zeolite should be determined by the reactivity for Cr(VI). The relative concentration of Cr(VI) BTC increased to the unit value while initial breakthrough was delayed and the propagation of breakthrough was slowed. In order to quantitatively describe the shape of Cr(VI) BTC, new parameters of ${\alpha}\;and\;{\beta}$ designated to be shape parameters, were defined and applied in contaminant transport concentration. These parameters were employed to represent the degree of initial breakthrough delay and the degree of breakthrough propagation, respectively. As initial contaminant concentration increased, ${\alpha}$ decreased, which indicated the delay of BTC's initiation. And as initial contaminant flow rate increased, ${\beta}$ decreased, which represented the faster propagation of the BTC. From these results, Fe-loaded zeolite was found to be an effective reactive material for PRBs against heavy metals having different ionic forms in groundwater. And it could be expected that as groundwater flows faster, the propagation of breakthrough would be faster and as contaminant concentration is higher, the initial point of breakthrough would appear earlier.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.373-379
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• 2009

Cesium carbonate was used as an adsorbent to capture carbon dioxide from gaseous stream of carbon dioxide, nitrogen, and moisture in a fixed-bed to obtain the breakthrough data of $CO_2$. The deactivation model in the non-catalytic heterogeneous reaction systems is used to analyze the sorption kinetics among carbon dioxide, carbonate, and moisture using the experimental breakthrough data. The experimental breakthrough data are fitted very well to the deactivation model than the adsorption isotherm models in the literature.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.596-598
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• 2006

본 논문에서는 수지 조성비 및 수지탑 배열이 이온교환 특성에 미치는 영향을 조사하기 위하여 전해질 농도는 $Na^+\;125ppm$, $Cl^-\;315ppm$ 유속은 500ml/min, 이온교환 수지는 ROHM&HAAS IR 120 양이온 수지와 ROHM&HAAS IRA 402 음이온 수지를 사용하였고, 수지탑 배열은 혼상-혼상-음이온, 혼상-음이온-혼상, 음이온-혼상-혼상 수지탑 순으로, 이온교환 수지탑의 양 음이온교환 수지의 조성 비율은 1:1, 1:2, 1:3 로 변화하여 실험한 결과 이온교환 수지의 조성비 변화에서는 양 음이온교환 수지 조성비 1:2의 경우 1:1, 1:3의 경우보다 파과시간이 연장되었다. 수지탑 배열이 음이온-혼상-혼상 수지탑인 경우 혼상-혼상-음이온 수지탑 배열과 파과시간을 비교해보면 약 60% 파과시간이 연장되었다. 따라서 수지탑 배열은 음이온-혼상-혼상 수지탑 순으로, 수지 조성비는 1:2일 때 가장 효율적인 것으로 나타났다.

• Journal of the Korean Institute of Gas
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• v.8 no.4 s.25
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• pp.36-41
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• 2004

The breakthrough curve was obtained to evaluate separation efficiency of clinoptilolite as an methane/nitrogen separation adsorbent. The Ca-exchanged clinoptilolite showed improved separation efficiency. The nitrogen adsorption capacity of Ca-clinoptilolite was increased with decreasing temperature. The temperature was decreased from 293K to 253K(feed gas flow rate : 670ml/min, pressure : 333kPa). The adsorption capacity is increased with increasing pressure. The pressure was increased from 333kPa to 700kPa(feed gas flow rate : 670ml/min, temperature : 253K, 293K).

• Clean Technology
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• v.20 no.2
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• pp.179-188
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• 2014

The effect of desorption pressure on $CO_2/N_2$ breakthrough behaviors for 4 different adsorbents was studied at a fixed bed. Zeolite 3A, 4A, 5A, and 13X pellets were used as adsorbents. Cyclic operations were executed with varying desorption pressure from vacuum (0 bar) to 3 bar while other conditions such as adsorption step pressure (3 bar), temperature (293 K), composition ($CO_2:N_2=10:90$vol%) and flow rate (400 ccm) were fixed at constant values. Each adsorption and desorption step was set as 80 min, which totaled up to 160 min per a cycle. 5 cycles with adsorption and desorption steps were run overall. After the experiment, breakthrough time, saturation time, and adsorption amount were measured and compared in order to find an optimum adsorbent and a proper operating condition for a post combustion $CO_2$ capture process.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.6
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• pp.533-544
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• 2021

Ion exchange (IX) performance on the exchanger bed is essentially evaluated for the generation of ultrapure water in electronics and chemical industries and for the corrosion control in nuclear power plants. The breakthrough characteristics of IX bed with multi-component were investigated with both cation- and mixed-IX beds of H- and ETAH-form for four kinds of cation exchange resins by using the combined solution of ethanolamine (ETA) and ammonia (NH₃) at trace NaCl. Unlike major components (ETAH⁺ and NH₄⁺ ), the phenomena of breakthrough and overshooting at bed outlet were not observed by Na⁺ over the test period (> 3 times theoretical exchange capacity of IX bed). The breakthrough from H-form resin bed was sequentially reached by ETAH⁺ and NH₄⁺, while the overshooting was observed for ETAH⁺ at the breakthrough of NH₄⁺. NH₄⁺ was 51.5% higher than ETAH⁺ in terms of the relative selectivity determined with the width of breakthrough zone. At the increased concentration of Na⁺ at bed inlet, the selectivity and the overshooting were decreased and increased, respectively. Na⁺ leakage was higher from ETAH-form resin bed and was not identical for four kinds of cation-exchange resins, which may be reduced by improving the intrinsic property of IX resin.

• Korean Chemical Engineering Research
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• v.47 no.4
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• pp.495-500
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• 2009

Activated carbon was used as an adsorbent to capture benzene vapor from gaseous stream of nitrogen in a fixed-bed to obtain the breakthrough data. The deactivation model is used to analyze the adsorption kinetics of benzene vapor using the experimental breakthrough data. The experimental breakthrough data are fitted very well to the deactivation model than the adsorption isotherm models in the literature.