• Polymer(Korea)
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• v.26 no.5
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• pp.551-558
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• 2002

It was observed that adsorption characteristics of sulfonated fabric ion-exchanger for separating nickel ion from electroplating rinse water. Swelling ratio was increased by increasing degree of sulfonation and polarity of solvent. Ion-exchange capacity was also increased by increasing degree of sulfonation and showed 3.38 meq/g at 16% sulfonated ion-exchanger. There was little effects of pH. Adsorption equilibrium was attained within 10 min, and adsorption rate was 7.5 mg/min. Adsorption capacity was not changed after 7 cycles of regeneration process. Regeneration adsorption capacity was slightly decreased to 2.01 meq/g. It confirmed that durability of sulfonated fabric ion-exchanger was suitable for adsorption process. Adsorption equilibrium time was linearly increased by increasing L/D and adsorption capacity showed the ion exchange capacity within the range of 2.71 ∼ 3.01 meq/g in continuous process. Design of adsorption column could be possible for L/D<2. Under constant L/D condition, there is no little pH effect when rinse water is acidic solution, and operation condition of adsorption process was optimized under pH 5.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.1119-1124
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• 2006

The objectives of this paper are to investigate the performance of silica gel-water adsorption refrigeration system with heat recovery process from the system experiment. This system can be driven by waste heat at near ambient temperature from $60^{\circ}C$ to $90^{\circ}C$. The cooling capacity and coefficient of performance(COP) were measured from various experimental conditions. An experimental results revealed the influence of operating temperatures(hot, cooling and chilled water), water flow rates, and adsorption-desorption cycle times on cooling capacity and COP. Under the standard conditions of $80^{\circ}C$ hot water, $25^{\circ}C$ cooling water, $14^{\circ}C$ chilled water inlet temperatures and 420sec cycle time, a cooling capacity of 1.14kW and a COP for cooling of 0.55 can be achieved.

• Journal of Environmental Health Sciences
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• v.19 no.4
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• pp.25-32
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• 1993

Granular activated carbon is commonly used in fixed-bed adsorbers to remove organic chemicals. In this experiment organic chemical solutions were prepared by adding the reagent grade organic chemical to distilled water. Isotherm adsorption tests of volatile organic chemicals were conducted using bottle-point technique and column test. Organic chemicals after passing through the column were extracted with hexane and analyzed with gas chromatography (Hewlett-Packard 5890) to check the adsorption capacity and breakthrough curve. The result were as follows: 1. The BET surface area of coconut activated carbon was 658~1,010 m$^2$/g where as coconut shell carbon was 6.6 m$^2$/g. Coconut activated carbon increased the BET surface area and adsorption capacity in bottle-point isotherm. 2. The adsorption capacity of coconut activated carbon for trichloroethylene (TCE) was reduced in the presence of humic substance. 3. A decrease in particle size of activated carbon resulted in higher adsorption capacity and lower intraparticle diffusion coefficient. It is reflected not only as a decrease in Freudlich adsorption capacity value (K) but also as an increase in Freudlich exponenent value (1/n).

• Analytical Science and Technology
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• v.13 no.3
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• pp.332-337
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• 2000

The study on the nitrogen adsorption, surface properties and water adsorption capacity of the carbonaceous desiccants derived from phenolic resin was carried out. In the nitrogen adsorption study on the carbonaceous desiccants, Type II isotherm for each sample was obtained. Furthermore, the adsorbed volume decrease with water washing of the desiccant. The $S_{BET}$ of the carbonaceous desiccants was $648.7m^2/g$ before washing and $189.3m^2/g$ after washing, respectively. The morphology of needlelike formation before washing and spherical particle after washing with water were observed from SEM micrographs. Finally, from the water adsorption effects, the percentage of the water loading capacity was 25-63%, and the capacity was good at relatively low humidity.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.116-124
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• 2007

An adsorption chiller is expected to have high energy-efficiency in utilizing the waste heat exhausted from a process. The objective of this paper is to investigate the performance of silica gel-water adsorption chiller from the cycle simulation and to provide a guideline for design of the adsorption chiller. The effect of cycle time, inlet temperature and water flow rate on the cooling capacity and COP is quantified during the cycle operation. It is found that the performance of adsorption chiller is more sensitive to the change of inlet water temperature rather than the water flow rate. It is concluded that the COP is 0.57 in the standard conditions(hot water $80^{\circ}C$, cooling water $30^{\circ}C$, chilled water inlet temperatures $14^{\circ}C$ and cycle time 420sec).

• Polymer(Korea)
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• v.26 no.1
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• pp.121-127
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• 2002

We investigated uranium adsorption and adsorption process characteristics in brine water, changing column bed height packed with amidoximated polypropylene-g- acrylonitrile (AOPP-g-AN) fibrous ion-exchanger. Swelling ratios of AOPP-g-AN in fibrous ion-exchanger were 8.54g/g $H_2O_2$ and 8.87 g/g for $H_2O_2$ solvent respectively. Ion exchange capacity increased with degree of graft and showed the maximum, 3.99 meq/g at 100% degree of graft. In batch process, uranium adsorption had reached an initial equilibrium in 10 min with the adsorption rate of 9.5 mg/min. Finial adsorption capacity was 3.95 meq/g, and pH effect could not be observed. In continuous process, adsorption capacity depended on various packing ratios and showed the maximum, 3.92 meq/g at L/D=1. In L/D<2, breakthrough curve was shown two step by channeling flow and ununiform adsorption. Breakthrough time and adsorption capacity were 26 min and 3.63 meq/g, respectively, in brine water adsorption. When compared with actual brine water and model solution, there was no significant difference of adsorption characteristics.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.4
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• pp.404-410
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• 2005

A series of batch type adsorption experiments were performed to remove aquatic phosphorus, where the layered double hydroxide (HTAL-CI) was used as an powdered adsorbent. It showed high adsorption capacity (T-P removal: 99.9%) in the range of pH 5.5 to 8.8 in spite of providing low adsorption characteristics (pH<4). The adsorption isotherm was approximated as a modified Langmuir type equation, where the maximum adsorption amount (50.5mg-P/g) was obtained at around 80mg-P/L of phosphorus concentration. A phosphate ion can occupy three adsorption sites with a chloride ion considering the result that 1 mol of phosphate ion adsorbed corresponded to the 3 moles of chloride ion released. Although the chloride ion at less than 1,000mg-CI/L did not significantly affect the adsorption capacity of phosphate, carbonate ion inhibited the adsorption property.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.389-395
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• 2006

The use of pine bark, a natural adsorbent prepared from Korean Red Pine (Pinus densifloral), was studied for its adsorption behavior of lead ion from aqueous solution. Adsorption experiments were carried out on lead ion concentrations of 10mg/L. Adsorption of lead ion could be described by both Langmuir and Freundlich adsorption isotherms. Treatment of the bark with nitric acid greatly increased initial adsorption rate, and equilibrium sorption capacity increased by approximately 48%. A pseudo second-order kinetic model fitted well for the kinetic behavior of lead ion adsorption onto the bark. Acid-treated bark demonstrated its adsorption capacity quite close to that of granular activated carbon. Results of this study indicated that ion exchange and chelation were involved in the adsorption process.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.83-87
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• 2012

Activated carbon fiber (ACF) was used to remove four kinds of trihalomethanes(THMs) from tap water which were remained as by-products during the chlorination of water. Adsorption capacity was investigated as a function of THMs concentration and solution temperature, and adsorption mechanism was studied in relating to the surface characteristics of ACF. All the four kinds of THMs were rapidly adsorbed on the surface of ACF by physical adsorption due to the enormous surface micropores and chemical adsorption due to the hydrogen bonds, showing a Langmuir type adsorption isotherm. Langmuir type is especially profitable for the adsorption of low level adsorptives. ACF was very effective for the removal of THMs from tap water because the THMs concentration is below $30{\mu}g/L$ in tap water. The adsorption amount of THMs on ACF increased in order of the number of brom atom; chloroform, bromodichloromethane, dibromochloromethane, and bromoform. The adsorption capacity increased as increasing the number of brom atom due to the decrease of polarity in solution. The adsorption capacity of THMs on ACF can be enhanced by proper surface treatment of ACF.

• Membrane and Water Treatment
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• v.11 no.2
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• pp.131-139
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• 2020

The current study focused on the preparation of low-cost PVC-based adsorbing membrane. Metakaolin, as available adsorbent, was embedded into the PVC matrix via solution blending method. The as-prepared PVC/metakaolin mixed matrix membranes were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), pure water permeability and contact angle measurements. The results confirmed the improvement of PWP and hydrophilicity due to the presence of metakaolin in the PVC matrix. Additionally the structure of PVC membrane was changed due to the incorporation of metakaolin in the polymer matrix. The static adsorption capacity of all samples was determined through dye removal. The effect of metakaolin dosage (0-7%) and pH (4, 8, 12) on dye adsorption capacity was investigated. The results depicted that the highest adsorption capacity was achieved at pH of 4 for all samples. Additionally, adsorption data were fitted on Langmuir, Freundlich, and Temkin models to determine the appropriate governing isotherm model. Finally, the dynamic adsorption capacity of the optimum PVC/metakaolin membrane was studied using dead-end filtration cell. The dye removal efficiency was determined for pure PVC and PVC/metakaolin membrane. The results demonstrated that PVC/metakaolin mixed matrix membrane had a high adsorption capacity for dye removal from aqueous solution.