• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.245-250
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• 2008

Adsorption experiment was carried out to find the adsorption capacity and characteristics of heavy metals(Cd, Pb) onto soil and mixed soil with food compost. Result showed that mixed soil having higher organic content adsorbed more heavy metal than soil, indicating that food compost can be used effectively to prevent soil pollution. Linear adsorption isotherm which adopted to find the adsorption characteristics was used to calculate Retardation Factor(R). The value of Retardation Factor(R)s of Pb and Cd in mixed soil, found as 34.54, 24.42 respectively, are higher than those in soil which were found as 4.64, 3.67, respectively. The value of Retardation Factor(R) using Freundlich adsorption isotherm could be presented by the functions of concentration and showed similar result as the linear one. But Freundlich adsorption isotherm showed higher relationship than linear one and the retardation factor(R) from freundlich adsorption isotherm was thought as more effective method to assess adsorption capacity because it could reflect gradient and intercept of the isotherm.

• Polymer(Korea)
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• v.26 no.4
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• pp.516-522
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• 2002

The ion exchange characteristic of quaternary ammonium as functional group containing aminated acrylic fibrous ion exchanger were studied for the adsorption of linear alkylbenzene sulfonate (LAS) in a continuous ion exchange process. The adsorption capacities of aminated acrylic for LAS as the adsorption temperature were increased with increasing adsorption temperature and were equilibrated at $40^{\circ}C$. The maximum adsorption capacities as column packing ratio (L/D) were obtained at L/D>2. The adsorption capacity for LAS was increased with increasing pH and the maximum adsorption capacity as pH was obtained at pH 7. The effects of temperature and pH were similar to those of flow rate and concentration of LAS tin the breakthrough curves, the breakthrough time and slope of breakthrough corves decreased with increasing flow rate and concentration of LAS in adsorption process.

• Journal of Environmental Science International
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• v.32 no.8
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• pp.563-572
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• 2023

Scoria from Jeju-island (Jeju scoria) was converted into zeolitic material (Z-SA) via zeolitification using the fusion/hydrothermal method. Jeju scoria could be synthesized into Z-SA to from a surface covered with Na-A zeolite crystals, which was confirmed through an analysis of X-ray diffraction peak patterns and scanning electron microscopy images. Jeju scoria and Z-SA were employed as adsorbents to evaluate the adsorption rate and adsorption capacities for Cu²⁺ and Zn²⁺ ions. The adsorption rates and isothermal adsorption capacities could be well fitted by the pseudo-quadratic adsorption kinetics and Langmuir adsorption isotherm, respectively. The maximum adsorption capacities (q_m) of Z-SA for Cu²⁺ and Zn²⁺ ions were found to be 163.36 mg/g and 120.51 mg/g, respectively, using the Langmuir adsorption isotherm. When Z-SA is synthesized from Jeju scoria via zeolitification using the fusion/hydrothermal method, Z-SA exhibits an adsorption capacity that is more than approximately 100 times the value exhibited by Jeju scoria. As a result, the synthesized Z-SA was regarded as an effective, economic adsorbent.

• Membrane and Water Treatment
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• v.9 no.2
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• pp.95-104
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• 2018

Copper pollution around the world has caused serious public health problems recently. The heavy metal adsorption on traditional membranes from wastewater is limited by material properties. Different adsorptive materials are embedded in the membrane matrix and act as the adsorbent for the heavy metal. The carbonized leaf powder has been proven as an effective adsorbent material in removing aqueous Cu(II) because of its relative high specific surface area and inherent beneficial groups such as amine, carboxyl and phosphate after carbonization process. Factors affecting the adsorption of Cu(II) include: adsorbent dosage, initial Cu(II) concentration, solution pH, temperature and duration. The kinetics data fit well with the pseudo-first order kinetics and the pseudo-second order kinetics model. The thermodynamic behavior reveals the endothermic and spontaneous nature of the adsorption. The adsorption isotherm curve fits Sips model well, and the adsorption capacity was determined at 61.77 mg/g. Based on D-R model, the adsorption was predominated by the form of physical adsorption under lower temperatures, while the increased temperature motivated the form of chemical adsorption such as ion-exchange reaction. According to the analysis towards the mechanism, the chemical adsorption process occurs mainly among amine, carbonate, phosphate and copper ions or other surface adsorption. This hypothesis is confirmed by FT-IR test and XRD spectra as well as the predicted parameters calculated based on D-R model.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.37-41
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• 2004

The removal efficiency of cadmium by chitosan complex isolated from Aspersillus oryzae was investigated through laboratory experiments. The results of the study are as follows. The adsorption kinetics of cadmium was reached the adsorption equilibrium in approximately 20 minutes and the removal efficiency was showed 95.8%. The effect of temperature on cadmium adsorption by chitosan complex shows that as the temperature increased, the amount of cadmium adsorption per unit weight of chitosan complex increased. The correlation between amount of cadmium adsorption per unit weight of chitosan complex and temperature was obtained through the coefficient of determination($R^2$). $R^2$ values was 0.854(p<0.05). A linearized Freundlich equation was used to fit the acquired experimental data. As a result, Freundlich constant, the adsorption intensity(1/n) was 0.550, and the measure of adsorption(k) was 2.181. So, it was concluded that adsorption of cadmium by chitosan complex is effective.

• Journal of the Korean Applied Science and Technology
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• v.21 no.2
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• pp.124-131
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• 2004

The adsorption of heavy metals in the waste water carried out on the various domestic clays and waste pottery. The effect of parameters such as pH, temperature, adsorption time and coexisting cations on the adsorption ability and characteristics were investigated to find out whether the clays could be used as adsorbents. Adsorption equilibrium was reached within 20 minutes on all the clays. The optimum pH was found to be above 5. When other cations such as Cu(II) or Zn(II) coexisted with Pb(II), the adsorption amount of Pb(II) decreased because of competing adsorption.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.286-296
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• 2007

To increase phosphate (P) availability in soils, the efficiency of silicate (Si) in reducing P adsorption was investigated by competitive adsorption tests under changing conditions of pH, ion concentrations, and order of anion addition along with single adsorption properties of each ion at $20^{\circ}C$. In the single ion adsorption study, P and Si ions showed the opposite reaction patterns: phosphate adsorption decreased with increasing pH and attained adsorption maximum however, silicate adsorption increased with increasing pH without attaining adsorption maximum. Phosphorus and Si adsorption were influenced by pH in the range of 5.0 - 9.0 and the type and amount of P and Si concentration. Silicate added to soil before P or in a mixture with P significantly reduced P adsorption above pH 7.0; however, there was no significant Si-induced decreased in P adsorption at pH 5.0 when anions were added as mixture. The efficiency of Si in reducing P adsorption increased with increasing Si concentration and pH. The effect of P on Si adsorption was relatively small at pH 5.0 and no effect of P on silicate adsorption was observed at pH 9.0. The presence of Si strongly depressed P adsorption when Si was added before P compared to P and Si added as a mixture. These results suggest that application of Si may decrease P adsorption and increase the availability of P in soils. Furthermore, a Si source would be better to add before P application to enhance the availability of P in soils.

• Analytical Science and Technology
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• v.5 no.1
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• pp.1-5
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• 1992

The adsorption amount of petroleum oil on XAD-4, XAD-7 and replacement adsorbents as rice bran, rice straw and sawdust were studied by using batch method measured in the optimum adsorption condition. The adsorption capacity of rice bran and rice straw of petroleum oil were excellent as well as adsorption ability about 50% of XAD resins and adsorption capacity of their replacement adsorbents were increased with optimum condition that pyrolysis time was 30 min. at $200^{\circ}C$. Adsorption ability of sawdust was very weak on the 30% MeOH aqueous medium but adsorption ability was range of about 50% of XAD resin's adsorption capacity on the 0.5M NaCl aqueous medium. Adsorption ability of rice bran and rice straw showed the same adsorption capacity even if difference external structure. Therefore, showing that rice bran and rice straw were have to good adsorption ability as replacement adsorbent for XAD resins.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.231-235
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• 1990

The activation energy of dissociative adsorption of oxygen on polycrystalline nickel surface is calculated from adsorption isotherms obtained using X-ray photoelectron spectroscopy. Negative value of this activation energy (-5.9 kJ/mol) indicates that the adsorption takes place through an undissociated precursor state. An adsorption energy for this precursor state is calculated assuming the precursor state as a moleculary physisorbed state ($E_{ad}$ = -7.9 kJ/mol). Finally, an adsorption isotherm equation is derived as a function of the gas exposure, which agrees with the experimental isotherms reasonably good.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1213-1223
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• 2000

The adsorption characteristics of phenol has been studied by using CDQ (Cokes Drying Quenching) dust as an adsorbent. The adsorption capacity of CDQ dust was shown to be 42% about removal for 300 ppm phenol solution at the equilibrium adsorption time of 60 min. Removal percentage of phenol increased as the initial phenol concentration was raised in the experimental conditions and the adsorption behavior was explained well by Freundlich adsorption isotherm. Kinetic study showed that the adsorption followed 1st, 1.5th, and 2nd-order rate equation in the sequence as the adsorption time passed. Since the adsorption amount of phenol was increased as the adsorption temperature was raised, the adsorption was thought to be endothermic, and several thermodynamic parameters have been calculated based upon experimental data. Adsorbed amount of phenol on CDQ dust changed little according to the variation in the solution pH except for the slight decrease under the strong alkaline condition.