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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal DOI :
The Korean Society of Clean Technology
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Volume & Issues
Volume 17, Issue 4 - Dec 2011
Volume 17, Issue 3 - Sep 2011
Volume 17, Issue 2 - Jun 2011
Volume 17, Issue 1 - Mar 2011
Selecting the target year
Self-healing Engineering Materials: I. Organic Materials
Choi, Eun-Ji ; Wang, Jing ; Yoon, Ji-Hwan ; Shim, Sang-Eun ; Yun, Ju-Ho ; Kim, Il ;
Clean Technology, volume 17, issue 1, 2011, Pages 1~12
Scientists and engineers have altered the properties of materials such as metals, alloys, polymers, ceramics, and so on, to suit the ever changing needs of our society. Man-made engineering materials generally demonstrate excellent mechanical properties, which often tar exceed those of natural materials. However, all such engineering materials lack the ability of self-healing, i.e. the ability to remove or neutralize microcracks without intentional human interaction. The damage management paradigm observed in nature can be reproduced successfully in man-made engineering materials, provided the intrinsic character of the various types of engineering materials is taken into account. Various self-healing ptotocols that can be applied for the organic materials such as polymers, ionomers and composites can be developed by utilizing suitable chemical reactions and physical intermolecular interactions.
Synthesis of Palladium Nanoparticles Encapsulated in Phosphine Ligand-Grafted Mesoporous Silicas and Their Application to Suzuki Cross-Coupling Reaction
Kim, Sang-Wook ; Joo, Jin ;
Clean Technology, volume 17, issue 1, 2011, Pages 13~18
Phosphine ligand-grafted mesoporous silica materials with large pores were prepared for the ligand-modified heterogeneous Pd nanocatalysts. New heterogeneous catalytic system was developed using palladium nanoparticles encapsulated in phosphine ligand-grafted mesoporous silica. The catalyst showed good catalytic activities for Suzuki cross-coupling using bromobenzene derivatives due to excellent phosphine ligand effects. Catalytic results showed nanoparticie catalysts can be recycled twice with decreased yields.
Measurement and Modeling of Bubble Points for Binary Mixtures of Carbon Dioxide and N,N-Dimethylformamide
Jung, Joon-Young ; Lee, Byung-Chul ;
Clean Technology, volume 17, issue 1, 2011, Pages 19~24
The bubble point pressures of binary mixtures of carbon dioxide (
) and N,N-dimethylformamide (DMF) were measured by using a high-pressure experimental apparatus equipped with a variable-volume view cell, at various
compositions in the range of temperatures above the critical temperature of
and below the critical temperature of DMF. The experimental bubble point pressure data were correlated with the Peng-Robinson equation of state (PR-EOS) to estimate the corresponding dew point compositions at equilibrium with the bubble point compositions. The experimentally measured bubble point pressures gave good agreement with those calculated by the PR-EOS. The variable-volume view cell equipment was verified to be an easy and quick way to measure the bubble point pressures of high-pressure compressible fluid mixtures.
Fabrication of Cell Chip through Eco-friendly Process
Jeong, Heon-Ho ; Song, Hwan-Moon ; Lee, Chang-Soo ;
Clean Technology, volume 17, issue 1, 2011, Pages 25~30
This study presents a fabrication method of cell-chip using aqueous solution based surface modification. The applications of cell-chip have potential for fundamental study of genetics, cell biology as well as cancer diagnostics and treatment. Conventional methods for fabrication of cell-chip have been limited in economic loss and environmental pollution because of the use of harsh organic solvent, complex process of silicon technology, and expensive equipment. In order to fabricate cell chip, we have proposed simple and eco-friendly process combined polyelectrolyte multilayer coating with microcontact printing. For the proof of concept, the cell chip can be applied to analyze the different expression of cell surface glycans and derivatives between cancer and normal cells. Our proposed method is useful technique for the application of novel cancer diagnostics and basic medical engineering.
Dehydration of D-xylose into Furfural Using Sulfonic Acid Modified
Kim, Eun-Gyu ; Kim, Saet-Byul ; Park, Eun-Duck ; Kim, Sang-Wook ;
Clean Technology, volume 17, issue 1, 2011, Pages 31~36
All types of
such as acidic, neutral and basic forms were chemically modified with (3-mercaptopropyl) trimethoxysilane (3-MPTMS) and oxidized by 30 wt%
solution. As a result, sulfonic acid modified
catalysts were obtained. Their formation was achieved more easily by treating 1M HCl solution. Their catalytic performance was tested by dehydration reaction of D-xylose to furfural. The sulfonic acid modified
catalysts showed high conversion (>90%) of D-xylose, and the selectivity to furfural was increased with the amount of sulfonic acid anchored on the catalyst.
Propylene Carbonate Synthesis using Supercritical
and Ionic Liquid
Kim, Byeong-Heon ; Jang, Sung-Hyeon ; Min, Se-Ryeon ; Kim, Hwa-Yong ;
Clean Technology, volume 17, issue 1, 2011, Pages 37~40
Some ionic liquids are suitable for catalysts and solvents which are applicable to
fixation reaction converting
to carbonate. Using the ionic liquids, the synthesis process will become greener and simpler because of easy catalyst recycling and unnecessary use of volatile and harmful organic solvents. In this work, the synthesis of propylene carbonate from propylene oxide using carbon dioxide and ionic liquids were measured at high pressures up to ~140 bar and at temperatures between
. As a results, we found the optimum condition and obtained the maximum yield under that condition.
CO Oxidation Over Manganese Oxide Catalysts: Effect of Calcination Temperature
Park, Jung-Hyun ; Kim, Yun-Jung ; Cho, Kyung-Ho ; Kim, Eui-Sik ; Shin, Chae-Ho ;
Clean Technology, volume 17, issue 1, 2011, Pages 41~47
]catalysts were prepared by precipitation method using potassium manganate and manganese acetate. The effect of calcination temperatures of
catalysts for CO oxidation has been studied and their physicochemical properties were studied by X-ray diffraction (XRD),
sorption, temperature programmed reduction of
), and temperature programmed desorption of CO (CO-TPD) techniques.
catalyst has a large surface area
having a narrow pore size distribution at 9 nm. The results of XRD and
showed that the catalysts calcined at different temperatures showed mixed oxidation states of Mn such as
. CO-TPD showed that the quantity of
desorbed was decreased with increasing the calcination temperatures. The catalytic activity over the catalyst calcined at
exhibited the highest conversion reaching to 100% at
vapor showed an inhibiting effect on the efficiency of the catalyst because of co-adsorption with CO on the active sites of manganese oxide catalysts and the initial catalytic activity of CO oxidation could be regenerated by removing
vapor in the reactants.
Characteristics of Titanium Dioxide-Impregnated Fibrous Activated Carbon and Its Application for Odorous Pollutant
Jo, Wan-Kuen ; Hwang, Eun-Song ; Yang, Sung-Bong ;
Clean Technology, volume 17, issue 1, 2011, Pages 48~55
The application of fibrous activated carbon (FAC)-titanium dioxide (
) hybrid system has not been reported yet for the control of malodorous dimethyl sulfide (DMS) at residential environmental levels. Accordingly, the current study was designed not only to characterize this hybrid system using x-ray diffraction method, particulate surface measurement and Fourier transform Infrared (FTIR) method, but also to evaluate its adsorptional photocatalytic activity (APA) for the DMS removal. The physical/surface characteristics of FAC-
which was prepared in this study suggested that the hybrid material might have certain APA for DMS. The Brunauer-Emmett-Teller (BET) specific area, total pore volume, micropore volume and mesopore volume decreased all as the
amounts coated on FAC increased, whereas the reverse was true for average pore diameter.
coated onto FAC did not influence the adsorptional activity of FAC for the DMS input concentration of 0.5 ppm. The APA test of the hybrid material presented that the initial removal efficiencies of DMS were 93, 78, 71 and 57% for the flow rates of 0.5, 1.0, l.5 and 2.0 L/min, respectively, and they decreased somewhat 2 h after the experiment started and kept almost constant for the rest experimental period. Under this pseudo-equilibrium condition, the DMS removal efficiencies were 78, 58, 53 and 36% for the four flow rates, respectively. Meanwhile, there were no significant byproducts observed on the surfaces of the hybrid material. Consequently, this study suggests that, under the experimental conditions used in the present study, the hybrid material can be applied for DMS at residential environment levels without being interfered by any byproducts.
Comparison of Analytical Methods of Products in Hydrocracking of Vacuum Residue
Kweon, Hyuk-Min ; Kim, Han-Na ; Huy, Chinh Nguyen ; Kim, Do-Kyong ; Kim, Do-Woan ; Oh, Seung-Hoon ; Shin, Eun-Woo ;
Clean Technology, volume 17, issue 1, 2011, Pages 56~61
In this study, hydrocarcking of vacuum residue was carried out in an autoclave reactor at
with a commercial catalyst (HDM) and the quantitative product distributions were analyzed by GC-SIMDIS method or simple distillation. During catalytic hydrocracking, thermal cracking also occurred together with catalytic cracking and the higher conversion and selectivity of gasoline and naphtha were obtained at high reaction temperature. GC-SIMDIS and simple distillation revealed different results for the analysis of products produced at different hydrocracking temperatures; almost same results were obtained for the product produced at
but different ones for the product produced at
. In the analysis of product produced at
, the GC-SIMDIS showed that a main product was VGO while a main product in the simple distillation was diesel, which implies that the simple distillation for the
reaction was not accurate due to thermal cracking of the product by the simple distillation.
Solid Flow Rate and Gas Bypassing with Operating Variables of J-valve in Multistage Annular Type Fluidized Beds
Hong, Yoon-Seok ; Kang, Gyung-Soo ; Park, Joo-Sik ; Lee, Dong-Hyun ;
Clean Technology, volume 17, issue 1, 2011, Pages 62~68
Hydrodynamic characteristics in multistage annular type fluidized bed (riser:
)were investigated. Glass beads (
, Geldart classification B) was used as a bed material. Accumulated weight by the electronic balance was measured to determine the solid flow rate in batch-type. In circulation condition, we measured the accumulated weight of particle transported from riser. At the steady state condition, solid circulation rate was calculated from time interval of the heated bed material passing between two thermocouples. Solid flow rate increased with increasing inlet gas velocity (
) and the static bed height (z, 0.24-0.68 m) from 2.2 to 23.4 kg/s. However, mean residence time decreased with increasing inlet gas velocity (
) and the static bed height (z, 0.24-0.68 m) from 1,438 to 440 s. The solid holdup in the riser was determined by measuring pressure differences according to the riser height. These results showed a similar trend to that of simple exponential decay type except for the top section of the riser. To verify the gas bypassing from top bubbling beds to middle bubbling beds,
gas was injected by tracer gas in constant ratio, and then was measured
concentration in outlet gas by gas chromatography. Gas bypassing occurred below 2.6% which is negligible value.
Conceptual Design and Hydrodynamic Properties of a Moving Bed Reactor for Intrinsic
Separation Hydrogen Production Process
Park, Dong-Kyoo ; Cho, Won-Chul ; Seo, Myung-Won ; Go, Kang-Seok ; Kim, Sang-Done ; Kang, Kyoung-Soo ; Park, Chu-Sik ;
Clean Technology, volume 17, issue 1, 2011, Pages 69~77
separation and hydrogen production system is a novel concept using oxidation and reduction reactions of oxygen carrier for both
capture and high purity hydrogen production. The process consists of a fuel reactor (FR), a steam reactor (SR) and an air reactor (AR). The natural gas (
) is oxidized to
and steam by the oxygen carrier in FR, whereas the steam is reduced to hydrogen by oxidation of the reduced oxygen carrier in SR. The oxygen carrier is fully oxidized by air in AR. In the present study, the chemical looping moving bed reactor having 200 L/h hydrogen production capacity is designed and the hydrodynamic properties were determined. Compared with other reactors, two moving bed reactors (FR, SR) were used to obtain high conversion and selectivity of the oxygen carrier. The desirable solid circulation rates are calculated to be in the range of
from the conceptual design. The solid circulation rate can be controlled by aeration in a loop-seal. To maintain the gas velocity in the moving beds (FR, SR) at the minimum fluidization velocity is found to be suitable for the stable operation. The solid holdup in moving beds decrease with increasing gas velocity and solid circulation rate.
Photo-Electrochemical Hydrogen Production Over P- and B- Incorporated
Nanometer Sized Photo-Catalysts
Kwak, Byeong-Sub ; Choi, Hee-Chan ; Woo, Jae-Wook ; Lee, Ju-Seung ; An, June-Bum ; Ryu, Si-Gyeong ; Kang, Mi-Sook ;
Clean Technology, volume 17, issue 1, 2011, Pages 78~82
For effectively photochemical hydrogen production, P (negative semiconductor) and B (positive semiconductor) ions (0.1, 0.2, 0.5, and 1.0 mol%) incorporated
(P- and B-
) nanometer sized particles were prepared using a solvothermal method as a photocatalyst. The characteristics of the synthesized P- and B-
photocatalysts were analyzed by X-ray Diffraction (XRD), Transmission electron microscopy (TEM), W-visible spectroscopy (UV-Vis), and Photoluminescence spectra (PL). The evolution of
from methanol/water (1:1) photo-splitting over B-
photocatalysts was enhanced compared to those over pure
photocatalysts; 0.42 mL of
gas was evolved after 10 h when 0.5 g of a 1.0 mol% B-
catalyst was used.