• Clean Technology
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• v.21 no.2
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• pp.108-116
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• 2015

Hydrogen sulfide and ammonia are one of the common malodorous compounds that can be found in emissions from many sewages treatment plants and industrial plants. Therefore, removing these harmful gases from emissions is of significance in both life and industry because they can cause health problems to human and detrimental effects on the catalysts. In this work, pyrolytic carbon blacks from waste tires were used to develop adsorbent with good adsorption capacity for removal of hydrogen and ammonia. Pellet-type adsorbents were prepared by a mixture of carbon black, metal oxide and sodium hydroxide or hydrochloric acid, and their adsorption capacities were estimated by using breakthrough curve of a continuous fixed bed adsorption column at ambient condition. The adsorbent manufactured with a mixture of carbon black, iron oxide(III) and sodium hydroxide showed the maximum working capacity of hydrogen sulfide. For ammonia, maximum working capacity was obtained by the adsorbent manufactured with a mixture of carbon black, copper oxide(II) and hydrochloric acid.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.190-198
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• 2008

In this stduy, the column experiments were carried out assuming the soil was contaminated by leakage of gasoline containing MTBE from USTs and pipes around gas stations. Then, characteristics of MTBE transport in the soil were investigated using CXTFIT program. The column experiments with different soil properties, moisture content, organic matter content and flow rate were carried out. Some parameters(D, R, $\beta$, $\omega$) used in two-site non-equilibrium adsorption model were obtained from measuring the MTBE concentration in injection-liquid and in effluent and using CXTFIT program. In addition, The characteristics of MTBE transport in the soil was found using BTCs and obtained parameters. Consequently, the advection decreased as the increase of the content of fine particle and organic, while the MTBE transport by advection was enhanced as increasing flow rate and moisture content.

• 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.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.51-57
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• 1999

Adsorption characteristics of Ni(II), Co(II) and Ag(I) ions on the Amberite IRN 77 cation exchange resin have been studied to suggest the guide-line for the optimum operation of demineralization process in primary coolant system during the shut-down period of pressurized water reactor(PWR). The adsorption mechanism of each metal ion, Ni(II), Co(II) or Ag(I) ion, on a cation exchange resin was well coincided with Langmuir isotherm. The adsorption and treatment capacities of $H^+$-form resin were higher than those of $Li^+$-form resin. In the continuous ion exchange process for the solution of multi-component system, the selectivity of the resin was in increasing order of Ni(II)${\approx}$Co(II)>Ag(I). In addition, the increase of the flow rate decreased the treatment capacity of the resin as well as the slope of the breakthrough curve.

• Journal of Radiation Protection and Research
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• v.29 no.1
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• pp.1-8
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• 2004

Diphosil, a new version of the organic-inorganic composite resin developed by ANL has a structure of the chelating diphosphonic acid groups grafted to a silica support. To apply Diphosil for the treatment of liquid radioactive waste from nuclear power plants, the adsorption equilibrium and column experiments were carried out for the main radionuclides, $^{137}Cs\;and\;^{60}Co$, in the liquid radwaste stream. Through the adsorption equilibrium experiments, the removal efficiencies of $^{137}Cs\;and\;^{60}Co$, and the effects of non-radioactive ions on the removal efficiency have been measured in various conditions using radiotracers. The breakthrough curves for the tested tracers were obtained from the laboratory scale column tests using the simulated liquid radioactive waste. In addition, the removal capacity of Diphosil is compared with that of Amberlite IRN 77 resin, generally used in nuclear power plants.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.73-80
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• 1998

Zinc titanate sorbents were prepared and regeneration of used sorbents for high temperature desulfurization of fuel gases was studied. Zn/Ti molar ratio of prepared sorbents was 1.5 and quartz fixed-bed reactors with 1 cm and 3 cm diameters were used. Regeneration of zinc titanate sorbents at high temperature is exothermic reaction; that brings about deterioration of sorbents. Therefore, we experimented regeneration reaction of zinc titanate sorbents for the purpose of obtaining the most suitable regeneration conditions by changing experimental parameters such as reaction temperature, oxygen concentration, flow rate and steam content. $H_2S$ and $SO_2$ breakthrough curves were obtained during desulfurization-regeneration. Also, properties of the sorbents before and after regeneration were analyzed using SEM, XRD, Hg-porosimetry and BET method. From such results, we obtained the most suitable regeneration conditions including regeneration temperature of 650$^{\circ}$C, $O_2$ content of 5% and steam content of 10% in the gas stream.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.1 no.1
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• pp.81-92
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• 2003

In order to predict the dynamic behaviors of uranium and cobalt in a fixed bed at various influent pH values of liquid waste, the adsorption system is regarded as a multi-component adsorption between each ionic species in the solution. Langmuir isotherm parameters of each species were extracted by incorporating equilibrium data with the solution chemistry of the uranium and cobalt using IAST. Prediction results were in good agreement with the experimental data, except for a high concentration and pH. Although there was some limitations in predicting the cobalt adsorption, this method may be useful in analyzing a complex adsorption system where various kinds of ionic species exist in a solution.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.452-456
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• 2008

Mesoporous silicate materials have been used as adsorbents due to the advantage of high specific surface area and regular mesopores. In this study, conventional mesoporous silicates (MCM-41, and SBA-15) were utilized as adsorbents for gaseous benzene, one of volatile organic compounds. In the results of the breakthrough curves of gaseous benzene, SBA-15 showed a higher benzene adsorption capacity in adsorption condition of this study. Especially, compared to benzene adsorption of zeolite X, that of SBA-15 was higher by a factor of 2.7. With increasing adsorption temperature, adsorption capacity for benzene of SBA-15 was decreased rapidly. This indicates that benzene adsorbed weakly on SBA-15.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.499-504
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• 2009

Erythrosine is used a food coloring, ink and dye, etc. but erithrosine is rarely used in United States due to its known hazards. The adsorption characteristics of erythrosine by granular activated carbon were investigated in the batch adsorber and the packed column. The adsorptivity of activated carbon for erythrosine were largely improved by pH control. When the pH was 11 in the sample, the erythrosine could be removed 98% of initial concentration. It was estabilished that the adsorption equilibrium of erythrosine on granular activated carbon was successfully fitted by Freundlich isotherm equation in the concentration range from 10mg/L to 1,000mg/L. The characteristics of breakthrough curve of activated carbon packed column depend on the design variables such as initial concentration, bed height, and flow rate.

• Clean Technology
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• v.16 no.3
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• pp.206-212
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• 2010

The adsorption characteristics of quinoline yellow by granular activated carbon were investigated experimently in the batch adsorber and packed column. The adsorptivity of activated carbon for quinoline yellow were largely improved by acidic pH and higher temperature. When the pH was 3 at $60^{\circ}C$, quinoline yellowcould be removed 97 percent of initial concentration(10 mg/L). It was estabilished that the adsorption equilibrium of quinoline yellow on granular activated carbon was successfully fitted by Freundlich isotherm equation in the temperature range from $25^{\circ}C$ to $60^{\circ}C$. The estimated values of k and ${\beta}$ are 38.71~166.60, 0.380~0.490, respectively. The breakthrough curve of activated carbon-packed column depends on the design variables such as initial concentration, bed height, and flow rate.