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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Korean Chemical Engineering Research
Journal Basic Information
Journal DOI :
The Korean Institute of Chemical Engineers
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Volume & Issues
Volume 42, Issue 6 - Dec 2004
Volume 42, Issue 5 - Oct 2004
Volume 42, Issue 4 - Aug 2004
Volume 42, Issue 3 - Jun 2004
Volume 42, Issue 2 - Apr 2004
Volume 42, Issue 1 - Feb 2004
Selecting the target year
Application of Microwave Energy in Chemical Engineering
Im, Ji-Un ; Hong, Seong-Soo ; Lee, Gun-Dae ; Park, Seong-Soo ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 485~493
The fast and convenient heating of foodstuffs in microwave ovens is routinely used in the common life. Recently, many researchers have recognized other potential applications for this method of heating, then have applied the rapid and selective heating associated with microwave technology to a number of useful processes. With the tool of the basic information required to apply the microwave technology to many processes, this paper reviewed briefly the principle and characteristic of microwave heating, the design of microwave unit, the interaction of microwave-matter, and the outlook of future microwave technology. Especially, it is focussed to explain the microwave thermal and nonthermal effects in organic synthesis based on medium effects and mechanistic considerations.
A Study on the Supercritical Carbon Dioxide Emulsion and Its Application
Park, Ji-Young ; Lim, Jong-Sung ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 494~509
Recently, the supercritical fluids technologies have been paid extremely increasing attention in the country. From now on, the supercritical technologies such as extraction/purification, SCORR (supercritical carbon dioxide photo-resist removal), DDS (drug delivery system), formation of functional structure of polymer or ceramic materials, preparation of metal oxide nano-particles, construction of database (DB), etc., will be investigated and developed more actively. The study on the supercritical emulsion among supercritical fluid technologies has been performed rigorously in advanced countries by recognizing its importance, however, a few researches are on progress in the country. The purpose of researching supercritical emulsion is mainly focused on the non-polar supercritical carbon dioxide and enhancing its application with polar substances. In this article, we are aimed to promote the research foundation of supercritical emulsion by reviewing in detail the supercritical
and by introducing preponderantly the researches about its application.
Kinetics of Heat Treatment for Metal (Fe or K) Impregnated Activated Carbons
Kim, Jun-Sik ; Lee, Jae-Kwang ; Kim, Sang-Do ; Lee, Chul-Wee ; Lee, Sang-Bong ; Choi, Myoung-Jae ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 510~517
Heat treatment of the activated carbons impregnated with Fe or K was carried out and these metal activated carbons (MAC) characterized by XRD, BET surface area, pore size distribution and
temperature programmed desorption (TPD). Also, The kinetics of the heat treatment was investigated by thermogravimetric analysis(TGA). Kissinger, Freeman-Carroll and Friedman method have been used to determine the activation energies. The mesopore volume of MAC was increased by heat treatment, but the micro volume and BET surface area decreased remarkably.
adsorption for the MAC is fond to be higher than the commercial activated carbon (CAC).
Fine Grinding Characterization of Alumina Ground by a Stirred Ball Attrition Mill
Kang, Dong-Min ; Moon, Dong-Ju ; Ryu, Jong-Woo ; Lee, Byung-Gwon ; Lee, Sang-Deuk ; Hong, Suk-In ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 518~523
To develop a high-performance structured catalyst, the fine grinding characteristics of alumina was investigated by a stirred-ball attrition mill. The grinding kinetics approach was successfully applied to the analysis of particle size distributions obtained under various grinding times. Particle size of alumina decreased with increasing grinding time and BET surface area increased with increasing the time. It was found that grinding rate constant decreased with increasing the solid content and media size. The particle size distributions estimated from grinding rate constant were in good agreement with the experimental data. It was found that the pH-value of the product suspension slightly increased due to increasing the specific surface area during the comminution. It was identified that nano-size alumina was produced by means of the stirred-ball attrition mill.
Electrolytic Decomposition Mechanism of Ammonia to Nitrogen at
Kim, Kwang-Wook ; Kim, Young-Jun ; Kim, In-Tae ; Park, Gun-Ill ; Lee, Eil-Hee ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 524~531
In order to know the electrolytic decomposition characteristics of ammonia to nitrogen, this work has studied an adsorption and a electrolytic reaction of ammonia at an
anode with a change of pH, and has evaluated the decomposition rate to nitrogen, the change of byproducts, and the effect of chloride ion on the decomposition reaction. Also, an electrolytic decomposition mechanism of ammonia was suggested. The ammonia in the basic solution was oxidized mainly to nitrogen gas through a direct electrolytic reaction accompanying adsorption at the electrode where the oxygen evolution hardly occurred. The ammonium ion in the neutral and acid solution could be partly decomposed to nitrogen by the OH radicals generated in the condition of oxygen evolution, not by the direct electrode reaction. However, the decomposition rate in the neutral or acid solution was much lower than that in the basic condition. The hypochlorite ion generated from chloride ion by the electrode was very effective for the decomposition of ammonia and ammonium ion to nitrogen. The ammonium ion by hypochlorite in neutral condition was partly changed to NOx gas as well as to nitrogen gas.
Capacitive Deionization by using Titania-incorporated Activated Carbon Paper
Kim, Chun-Joong ; Seo, Gon ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 532~537
Titania was incorporated on activated carbon paper by reacting titanium butoxide with it. The oxidation state of titanium was +4 and its incorporated amount was 2.5 wt% as titania. The titania incorporation on the paper increased its electric field adsorption of NaCl by four times, resulting in a significant enhancement of its capacitive deionization performance. The feasibility of the titania-incorporated activated carbon paper as a capacitive deionization electrode was discussed based on its physical and electric field adsorptions of various electrolytes measured at different temperatures and electric potential differences.
The Monitoring of Chemical Process using The Support Vector Machine
Lee, Chang-Jun ; Song, Sang-Ok ; Yoon, En-Sup ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 538~544
In this paper, fault detection and diagnosis model using SVM (support vector machine) is proposed. This model is applied to develop inferential model that detects faults of a chemical process and diagnoses them. The existing multivariate method including PLS and Neural Network has been shown to be a powerful technique for process modelling and multivariate statistical process control. However, for systems that exhibit non-linear behavior and have sparse data, they can be inappropriate. In this paper by using SVM regression, more accurate and fast fault detection model is proposed. And then SVM classification is used for fault diagnosis model using known fault data. To verify the superior performance of the proposed model, the data sets of Tennessee Eastman Process are applied.
Phase Behavior of Poly(L-lactide) and Polycaprolactone in Binary Mixtures including
at High Pressure
Kim, Jae-Duck ; Park, Ji-Young ; Lee, Youn-Woo ; Lim, Jong-Sung ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 545~550
We measured cloud points using the high-pressure variable volume cell apparatus for poly(L-lactide)(L-PLA) and polycaprolactone(PCL) in various solvents. The solvents used for dissolving poly(L-lactide) and polycaprolactone were HCFC-22(chlorodifluoromethane) and DME(dimethylether),
. In case of L-PLA, it was dissolved well in HCFC-22 in the pressure range 4.0-15.0 MPa and the temperature range 344-393 K, and exhibited LCST(lower critical solution temperature) behavior in HCFC-22 and
. In case of polycaprolactone, it was dissolved well in DME and HCFC-22 in the pressure range 13-37 MPa and 3-27 MPa respectively, in the range 310-415 K, and also exhibited LCST behavior in DME, HCFC-22,
. The cloud point pressure of both poly(L-lactide) and polycaprolactone increased proportionally to the amount of
added at the same temperature. According to these results, it was known that
could be used as an anti-solvent, and the cloud point of poly(L-lactide) and polycaprolactone could be controlled by changing the concentration of
Propylamine Adsorption Characteristics of Surface-treated Activated Carbon Fibers with Nitric Acid and Sulfuric acid
Kim, Byeoung-Ku ; Yang, Burm-Ho ; Ryu, Seung-Kon ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 551~557
The surface of rayon-based activated carbon fiber (ACF, KF-1500) was treated by
. Structural properties and surface functional groups of the ACFs were analyzed and prophylamine adsorption characteristics of the ACFs were also investigated. The specific surface area and total pore volume of ACFs decreased about 5-8 wt% by acidic treatment at boiling point, while total surface acidity highly increased. The total surface acidity of nitric acid treated ACF was 10 times larger than that of non-treated ACF and 3.3 times larger than that of sulfuric acid treated ACF. Especially, carboxylic and phenolic groups of ACF were much developed by nitric acid treatment. The propylamine adsorption amount of ACF treated by nitric acid was 350 mg/g-ACF at relative pressure of 1.0 and increased 17% more than that of non-treated ACF. Also, the equilibrium adsorption isotherm was well fitted to Freundlich equation. This remarkable increase on propylamine adsorption capacity of nitric acid treated ACF was due to the large increase of carboxylic and phenolic groups on the surface.
Pervaporation of Water/Ethanol Mixture through NaY Zeolite Membrane
Ahn, Hyo-Seong ; Lee, Hye-Ryeon ; Lee, Yong-Taek ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 558~563
Membrane pervaporation has shown many advantages over distillation for separation of water/organics mixtures since not only it requires a low energy demand but also it provides the ability to separate azeotropic mixtures. Zeolite membranes might show better thermal, mechanical, chemical stabilities than polymer membranes. Water could be effectively separated from water/organic mixtures using the NaY zeolite membrane because of its high hydrophilicity. In this study, water was separated from water/ethanol mixtures by pervaporation using NaY zeolite membrane synthesized in our laboratory. As a mole fraction of ethanol increased, a total permeation flux decreased and a separation factor also decreased. As an experimental temperature increased, a total permeation flux increased while a separation factor decreased. It was found that the NaY zeolite membrane showed better performance on water/ethanol separation than that of a distillation process or PVA polymeric pervaporation membranes.
Pervaporation of TFEA/Water Mixtures Through NaA Zeolite Membrane Hydrothermally Synthesized
Lee, Hye-Ryeon ; Ahn, Hyo-Seong ; Lee, Soo-Bok ; Lee, Yong-Taek ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 564~569
Pervaporation is mainly used to separate liquid mixtures because not only it exhibits a high selectivity compared with traditional distillation processes, but also it is known to be an energy saving separation process. The NaA zeolite membranes was prepared on the inner surface of a porous
tube using a hydrothermal synthesis. The NaA zeolite crystals and the surface morphology of the membrane were characterized by X-ray diffraction and scanning electron microscope. The total flux was about
and the separation factor was in the range of 4,800-660,000. The separation performance through the NaA membrane was found to be superior to that with a distillation process by comparison of the vapor-liquid equilibrium data.
Effect of PVA Addition on the Properties of Alumina Membranes
Park, Ja-Lyong ; Lee, Dong-Il ; Park, Kwon-Pil ; Kim, Tae-Hwan ; Sung, Jae-Suk ; Song, Ki-Chang ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 570~576
Boehmite sol was prepared using aluminum isopropoxide (AIP) as a starting material through the process of hydrolysis/peptization by a sol-gel method. Poly (vinyl alcohol) (PVA) as a binder was added to the boehmite sol after the peptization step. Supported
membranes were prepared by dip-coating the boehmite sol on
support. The effect of PVA addition to the boehmite sol on crystalline size, specific surface area, and pore size was studied, as well as crack formation during drying of the membrane. The addition of PVA resulted in a crack-free
membrane with a larger pore diameter and crystalline size and a higher specific surface area compared to a membrane prepared without PVA.
Computational Analysis of Particle Behavior in a Ceramic Candle Filter Vessel with an Inlet at Different Location
Park, Seok-Joo ; Park, Young-Ok ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 577~587
Computational simulation was performed to analyze fluid flow and particle trajectories in a filter vessel with different location of an inlet including ceramic candle filters to remove dust particles from exhausted gas at high temperature and/or high pressure conditions. The inlet is located at the upper, bottom or middle position of centerline of the vessel. Computational results show that the particle deposition distribution is most uniform and the concentration of large particles is lowest on the filter surface in the filter vessel with the middle inlet among three inlets. Consequently, the amount of particles approaching filter surface may be reduced and the dust layer on the surface uniform when inlet flow does not directly contact with filters but is indirectly injected to a mixing region of the vessel.
Criteria for Selection of Metal Component in Oxygen Carrier Particles for Chemical-Looping Combustor
Ryu, Ho-Jung ; Jin, Gyoung-Tae ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 588~597
To provide criteria for selection of metal component in an oxygen carrier particle for a chemical-looping combustor, applicable metal components were selected by consideration of physical properties such as melting point and atomic weight (molecular weight). For the applicable metal components, possible reduced and oxidized phases were considered. Next, we investigated heat of reaction, oxygen transfer capacity, and crystal structures identified by XRD analysis in the previous studies. We found that Ni has an appropriate heat of oxidation and reduction, excellent performance in oxygen transfer capacity, and fixed reduced and oxidized phase. Therefore, Ni was selected as the best metal component for the oxygen carrier particle. We provide guideline for selection and development of oxygen carrier particle by performance estimation of chemical-looping combustor with variations of metal oxide content and pressure.
Electrical Conductivity and Surface Temperature of Carbon Fiber Reinforced Paper
Jang, Joon ; Ryu, Seung-Kon ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 598~604
Carbon fiber reinforced paper (CFR-paper)s were prepared by the handsheet manufacturing method with a mixture of wood pulp as a binder and carbon fiber as a reinforcing material. The CFR-paper samples were prepared by varying the sources and contents of carbon fibers, and the weight of paper. Though the 5 mm chopped carbon fibers were evenly dispersed in the paper, the increase of carbon fiber content weakened the property of the papers. The electrical conductivity of the paper increased with an increase of carbon fiber content and reached to the level of 0.609 S/cm at 50 wt% anisotropic pitch based carbon fiber in the
basis weight of paper. The surface temperature of reinforced paper linearly increased as increasing the carbon fiber content.
Crystallization and Dynamic Mechanical Properties of Polybutylene terephthalate(PBT)/Montmorillonite Nanocomposite
Kim, Suk-Soo ; Chang, Young-Wook ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 605~611
Poly (butyleneterephthalate) (PBT)/montmorillonite (MMT) hybrid nanocomposite was prepared via melt intercalation using a co-rotating twin screw extruder. From the analysis using X-ray diffraction (XRD) and transmission electron microscope (TEM), it was confirmed that the PBT/MMT hybrid forms an intercalated structure in which MMT particles are partially exfoliated and are dispersed uniformly in the PBT matrix. The effect of clay layers on the non-isothermal crystallization behaviors of PBT was investigated by differential scanning calorimetry (DSC), and modified Avrami analysis was used for the interpretation of the results. It was found that the introduction of nano-size clay layers accelerates the non-isothermal crystallization process of PBT and the clay layers act as nucleating agents. Dynamic mechanical analysis for the nanocomposite showed that storage modulus of the PBT matrix was increased by more than 40% over whole temperature range on the addition of MMT by 5 wt%, but the change in glass transition temperature was marginal.
Physical Effect on Synthesis of Al(III) Polymeric Inorganic Coagulants for Water Treatment
Han, Seung-Woo ; Lee, Chul-Woo ; Kang, Lim-Seok ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 612~618
This research explored the feasibility of preparing preformed PACl (polyaluminum chloride) as coagulants for water treatment at optimum synthesized condition. The optimum synthesized condition of PACls was that the G value and temperature were
, respectively. The differentiation and quantification of hydrolytic Al species in coagulant were done by spectrophotometric method based on the interaction of Al with Ferron as a complexing agent. In addition,
and FT-IR were used to characterize the nature and structure of the hydrolytic species in the synthesized coagulants. The properties of the synthesized polyaluminum chloride (PACl) showed that the quantities of polymeric Al produced at a value of
at 2.2 exhibited a maxima at 85% of the total aluminum in solution. The synthesized PACl was stable during storing period indicating the aging effect is negligible.
Preparation of Nafion/polystyrene Composite Membranes using Supercritical
Impregnation for DMFCs
Sauk, Jun-Ho ; Byun, Jung-Yeon ; Kang, Yu-Chan ; Kim, Hwa-Yong ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 619~623
Grafting of styrene onto nafion membranes was carried out by the impregnation and radical polymerization in the supercritical carbon dioxide (
) as a solvent and swelling agent. In impregnation process, certain amounts of
was charged into the apparatus until desired pressure was reached. Styrene monomer, initiator 2,2'-azoisobutyronitrile (AIBN) and crosslinker divinyl benzene (DVB) were impregnated into nafion membranes at
for 4 h. After releasing
, the polymerization step then was started by raising the temperature to
and carried out at a pressure of 10 MPa for 4 h. The grafted membranes (N-g-ps) have been sulfonated to various degrees in concentrated sulfuric acid (
) at room temperature or
. The sulfonated membranes (N-g-pssa) were characterized by measuring their ion exchange capacities (IEC), wateruptake, ion conductivity and methanol permeation. The structure and morphology of these membranes were observed with fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The permeability of methanol in nafion 115 was higher, with a value of
than that of a N-g-pssa membrane. The permeabilities of the N-g-pssa membranes decreased with increasing concentration of DVB, i.e. from
. The N-g-pssa membranes (without DVB) has the best cell performance at 0.35 V because this membrane probably has the highest ion conductivity (0.0461 S/cm) and lower methanol permeability than that of Nafion 115.
Enhancing Thermal Conductivity of Nanofluids Containing Carbon Nanotubes
Cho, Tae-Hyun ; Park, Sang-Do ; Lee, Young-Seak ; Baek, Il-Hyun ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 624~629
Nanofluids, the suspension of carbon nanotubes (CNTs) in ethylene glycol which can be used as heat transfer fluid having high thermal conductivity, were prepared by dispersion of CNTs in ethylene glycol using direct and acid treatment dispersion methods. Direct dispersion method was achieved by sonication of ethylene glycol having CNTs (SCNT) or by sonication after dissolution of PAA-co-AA (polyacrylamide-co-acrylicacid) stabilizer into above ethylene glycol (D-CNT). Acid treatment dispersion method was done by sonication of ethylene glycol involving CNTs treated the surface with acids (A-CNT). The thermal conductivities of nanofluids were measured by hot wire method. The thermal conductivities of S-CNT, D-CNT, and A-CNT containing 1 vol% of CNTs increased up to 16, 14, and 15%, compared to that of pure ethylene glycol. The thermal conductivities of nanofluids prepared by S-CNT increased up to 16, 19, and 23% with increasing CNTs concentrations of 1, 2, and 3 vol%, respectively.
The Performance of Direct Formic Acid Fuel Cells with Various Catalysts
Kim, Jeong-Soo ; Ruy, Jae-Kun ; Jung, Eun-Mi ; Lee, Hyo-Song ; Kim, Jin-Yong ; Kim, Yeong-Chun ; Han, Jong-Hee ; Oh, In-Hwan ; Lee, Young-Woo ;
Korean Chemical Engineering Research, volume 42, issue 5, 2004, Pages 630~634
Fuel cell performance using formic acid as a fuel has been examined with various anode catalysts. Also the optimum conditions were investigated for the high performance of the direct formic acid fuel cell(DFAFC). The change in the flow rate of formic acid had only a slight effect on the performance of fuel cell. The best performance was shown at 9 M formic acid. Power density increased about
with an increase in the loading of Pt-Ru black catalyst from
. The highest power density was
with a Pt-Ru black catalyst of
and 9 M formic acid feed. Finally the open circuit potential(OCP) was the highest for Pt-Pd catalyst at about 0.820 V, including that Pt-Pd was the most suitable catalyst for oxidation of formic acid.