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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 50, Issue 6 - Dec 2012
Volume 50, Issue 5 - Oct 2012
Volume 50, Issue 4 - Aug 2012
Volume 50, Issue 3 - Jun 2012
Volume 50, Issue 2 - Apr 2012
Volume 50, Issue 1 - Feb 2012
Selecting the target year
Decrease of PEMFC Performance by Ion Contamination
Song, Jinhoon ; Woo, Myungwu ; Kim, Saehoon ; Ahn, Byungki ; Lim, Taewon ; Park, Kwonpil ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 187~190
DOI : 10.9713/kcer.2012.50.2.187
Contamination of ion from cathode air on the membrane and electrode assembly (MEA) is the serious degradation source in proton exchange membrane fuel cells (PEMFC). In this study, concentration of ions in air at industry region, street and seaside were measured. There were comparably high concentration of
in this regions. This paper shows the effects of MEA contamination by these ions generated from humidification water. After 170 hours of fuel cell operation using city water as humidification water, the performance of unit cell decrease to 11% of initial performance. The electrolyte membrane easily absorbed foreign contaminant cations due to the stronger affinity of foreign cations with the sulfonic acid group compared to
. The contaminant ions existing in the interface between the platinum catalyst and ionomer layer turn out to be the most serious factor to decrease cell performance.
Effect of Addition of Pentaerythritol Triacrylate and Silane Coupling Agents on the Properties of Waterborne Polyurethane
Shin, Yong Tak ; Hong, Min Gi ; Kim, Byung Suk ; Lee, Won Ki ; Yoo, Byung Won ; Lee, Myung Goo ; Song, Ki Chang ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 191~197
DOI : 10.9713/kcer.2012.50.2.191
Acrylic terminated polyurethane prepolymers were synthesized by capping the NCO groups of polyurethane prepolymers, prepared from isophorone diisocyanate (IPDI), polycarbonate diol (PCD) and dimethylol propionic acid (DMPA), with pentaerythritol triacrylate (PETA). Subsequently, silylated acrylic terminated prepolymers were prepared by capping the NCO groups of acrylic terminated polyurethane prepolymers with different types of silane coupling agents, glycidoxypropyl trimethoxysilane (GPTMS) or aminopropyl triethoxysilane (APS). The average particle size of pure waterborne polyurethane solution, measured by the dynamic light scattering method, was increased from 14.3 nm to 208.6 nm by adding PETA and APS. Also, the coating film of silylated acrylic terminated waterborne polyurethane showed better abrasion resistance and pencil hardness than that of pure waterborne polyurethane.
Reactive Dye(RB-8, RB-49, RR-218) in Crystallization and Characteristic of Population Density
Han, Hyunkak ; Lee, Jonghoon ; In, Daeyoung ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 198~203
DOI : 10.9713/kcer.2012.50.2.198
Salting-out technique was adopted to crystallize dye crystals from dye solution. In this research solubility of dye solution and crystallization kinetics of Reactive dye (RB-8, RB-49, RR-218) was investigated. The empirical expressions of salting-out crystallization kinetics for Reactive dye (RB-8, RB-49, RR-218) in continuous MSMPR crystallizer was RB-8 in crystal growth kinetics
and nucleation kinetics
, RB-49 in crystal growth kinetics
and nucleation kinetics
, RR-218 in crystal growth kinetics
and nucleation kinetics
. Also, comparison of calculated crystal size distribution applying to characteristic curve method with experimental crystal size showed good agreement.
Preparation of Nickel Oxide Films by Anodizing
Kim, Youngjin ; Jung, Jihoon ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 204~210
DOI : 10.9713/kcer.2012.50.2.204
Nickel oxide thin films with 2.3
thickness were prepared in order to overcome limitations of thickness with nm dimension by anodizing. For the electrolyte, ethylene glycol was used as solvent, and
was added for source of
ions. The anodizing experiments were carried out on various voltages such as 40, 60 V and 80 V for 12 hours. The thickness of NiO was changed according to the anodizing time and the voltage. However, destruction of Ni caused by rapid oxidation reaction occurred at 80 V. XRD results show that NiO was successfully created by anodizing.
Wet Etching of Stainless Steel Foil by Aqueous Ferric Chloride Solution
Lee, Hyung Min ; Park, Mooryong ; Park, Gwang Ho ; Park, Chinho ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 211~216
DOI : 10.9713/kcer.2012.50.2.211
Wet chemical etching of stainless steel foil by aqueous ferric chloride solution was investigated in this study. Effects of various process parameters (e.g. etchant agitation rate, etchant temperature,
ion concentration, free HCl concentration, specific gravity, etc.) on the etch rate was first studied, and it was found that the etch rate of AK (aluminum-killed) steel, chromium metal and stainless steel (STS430J1L alloy) follows the pseudo-first order reaction equation. When the fatigue ratio of etchant was kept under 16%, sludge was not formed in the solution, and the etched surface showed smooth roughness. The etch rate decreases as Baume of etchant increases, but the effect of free HCl concentration on the etch rate turned out to be minimal. Experimental data were compared with the calculated results from modeled equation, showing very good agreement.
Effect of ZnCl
Co-catalyst in the Synthesis of Dimethyl Carbonate from Ethylene Carbonate and Methanol by Using Base Catalysts
Kim, Dong-Woo ; Park, Moon-Seok ; Kim, Moon-Il ; Park, Dae-Won ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 217~222
DOI : 10.9713/kcer.2012.50.2.217
The synthesis of dimethyl carbonate(DMC) is a promising reaction for the use of naturally abundant carbon dioxide. DMC has gained considerable interest owing to its versatile chemical reactivity and unique properties such as high oxygen content, low toxicity, and excellent biodegradability. In this study, the synthesis of DMC through the transesterification of ethylene carbonate(EC) with methanol was investigated by using ionic liquid and metal oxide catalysts. The screening test of different catalysts revealed that choline hydroxide ([Choline][OH]) and 1-n-butyl-3-methyl imidazolium hydroxide([BMIm][OH]) had better catalytic performance than metal salts catalysts such as MgO, ZnO and CaO. The effects of reaction parameters such as reaction temperature, MeOH/EC mole ratio, and carbon dioxide pressure on the reactivity of [Choline][OH] catalyst were discussed. High temperature and high MeOH/EC mole ratio were favorable for high conversion of EC. However, the yield of DMC showed a maximum when carbon dioxide pressure was 1.34 MPa, and then it decreased for higher carbon dioxide pressure. Zinc chloride(
) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the EC conversion and DMC yield probably due to the acid-base properties of the catalysts.
Liquefaction Characteristics of ABS-polyethylene Mixture by a Low-Temperature Pyrolysis
Choi, Hong-Jun ; Jeong, Sang Mun ; Lee, Bong-Hee ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 223~228
DOI : 10.9713/kcer.2012.50.2.223
The low-temperature pyrolysis of ABS, polyethylene (PE) and an ABS-polyethylene (ABS-PE) mixture was conducted in a batch reactor at
. The conversion and the product yield were measured as a function of the reaction time with a variation of the mixture composition. The oil products formed during pyrolysis were classified into gas, gasoline, kerosene, gas oil and heavy oil according to the petroleum product quality standard of the Ministry of Knowledge Economy. The pyrolysis conversion increases with an increase in the content of PE. The yield of the pyrolytic products was ranked as heavy oil>gas>gasoline>gas oil>kerosene as the content of PE in the mixture increases.
Phosphorus Modified Co/Al
Fischer-Tropsch Catalyst for a Slurry Phase CSTR with Enhanced Hydrothermal and Mechanical Stability
Jung, Gyu-In ; Ha, Kyoung-Su ; Park, Seon-Ju ; Kim, Du-Eil ; Woo, Min-Hee ; Jun, Ki-Won ; Bae, Jong-Wook ; Kang, Yong ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 229~237
DOI : 10.9713/kcer.2012.50.2.229
Phosphorus was incorporated into Co/
catalyst for FTS by impregnating an acidic precursor, phosphoric acid, in
support to improve the mechanical strength, the hydrothermal stability of the catalyst particle, and the catalytic performance as well. Surface characterization techniques such as FT-IR revealed that
phase was generated on the surface of the P-modified catalyst. The addition of phosphorus was found to alleviate the interaction between cobalt and alumina surface, and to increase reducibility of catalyst. The catalytic activity such as
productivity and turnover frequency (TOF) was calculated to evaluate catalytic performance. The influence of calcination temperature of the
containing 2 wt.% P on the catalytic performance was also investigated. Through hydrothermal stability test and XRD analysis, the P-modified catalyst had strong resistant to the pressurized and hot
. The mechanical strength of the P-modified catalyst was also examined through an in-house fluidized-bed vessel, and it was found that the catalyst fragmentation could be successfully suppressed with P. Taken as a whole, the best performance was shown to be at 1~2 wt.% P in alumina and at the calcination temperature of
Extraction of Carbohydrates and Minerals from Laminaria Using Organic Acid
Chun, Ji Yeon ; Han, Cha Seong ; Lee, Jung Shik ; Kim, Young Suk ; Park, Kwon Pil ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 238~243
DOI : 10.9713/kcer.2012.50.2.238
Laminaria roots have not been practically used in Korea. In this study, the extraction process of carbohydrates and minerals from Laminaria roots was investigated and the properties of extracted components were measured. Hydrochloric acid generally used in carbohydrate extraction from seaweeds in order to obtain high extraction yield. But in this work, to utilize extracted components as a functional food material, organic acids such as citric acid were used. Organic acid as extraction solvent has low extraction yield compared to strong acids. Therefore optimum condition for maximum yield was investigated in carbohydrate extraction from Laminaria roots using organic acid. We measured the extraction yields of carbohydrate with variation of extraction temperature, extraction time, concentration of organic acid and particle size of samples. The extraction yield increased as the particle size decreased and temperature became high. The extraction yield was 19.0 wt% after 4.0 hours extraction with 0.2 wt% citric acid at
. Potassium concentration was high compared other minerals in extraction solution, that is, the ratio of K/Na was about 3.0. Fucoidan from Laminaria roots had same carbohydrate composition and lower molecular weight compared that of Undaria pinnatifida.
Separation of Carbon Dioxide Using Pelletized Zeolite Adsorbent with Amine Impregration
Hong, Mi So ; Pankaj, Sharma ; Jung, Yun Ho ; Park, Sung Youl ; Park, So Jin ; Baek, Il Hyun ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 244~250
DOI : 10.9713/kcer.2012.50.2.244
In order to separate of carbon dioxide in the combustion exhaust gas, monoethanolamine (MEA) and piperazine (PZ) impregnated zeolite 13X adsorbents were used. A series of adsorbents were synthesized by impregnating 30, 50 and 70 wt% of MEA and PZ respectively on zeolite 13X pellet. XRD, FT-IR and BET were used to characterize the properties of impregnated pelletized zeolite 13X absorbents. In order to investigate the separation characteristics of carbon dioxide, zeolite pellet, MEA impregnated zeolite and PZ impregnated zeolite pellet were investigated at 25, 50 and
. Amine impregnated pelletized zeolite absorbent has shown that adsorption decreases with increasing temperature. Finally, the carbon dioxide adsorption capacity when emission temperature of the combustion exhaust gas, PZ impregnated zeolite pellet was 1.8 times than zeolite pellet as well as 20 times than MEA impregnated zeolite pellet.
Etherification of n-Butanol to Di-n-Butyl Ether over H
(x=0, 1, 2, 3) Keggin and H
(x=0, 1, 2, 3) Wells-Dawson Heteropolyacid Catalysts
Kim, Jeong Kwon ; Choi, Jung Ho ; Yi, Jongheop ; Song, In Kyu ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 251~256
DOI : 10.9713/kcer.2012.50.2.251
Etherification of n-butanol to di-n-Butyl Ether was carried out over Keggin
(x=0, 1, 2, 3) and
(x=0, 1, 2, 3) Wells-Dawson heteropolyacid catalysts. Niobium-substituted Keggin and Wells-Dawson heteropolyacid catalysts with different niobium content were prepared. Successful preparation of the catalysts was confirmed by FT-IR, ICP-AES, and
NMR analyses. Their acid properties were determined by
-TPD (Temperature-Programmed Desorption) measurements. Heteropolyacid catalysts showed different acid properties depending on niobium content in both series. The correlation between acid properties of heteropolyacid catalysts and catalytic activity was then established. Acidity of Keggin and Wells-Dawson heteropolyacid catalysts decreased with increasing niobium content, and conversion of n-butanol and yield for di-n-butyl ether increased with increasing acidity of the catalysts, regardless of the identity of heteropolyacid catalysts (without heteropolyacid structural sensitivity). Thus, acidity of heteropolyacid catalysts served as an important factor determining the catalytic performance in the etherification of n-butanol to di-n-Butyl Ether.
Energy Consumption of Biodiesel Production Process by Supercritical and Immobilized Lipase Method
Min, Eung-Jae ; Lee, Euy-Soo ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 257~263
DOI : 10.9713/kcer.2012.50.2.257
Biodiesel is a renewable energy which is nontoxic and acting as a replacement for conventional diesel which derived from fossil fuel. Classified biodiesel producing way such as acid, base, supercritical and enzyme methods, this study focused on eco-friendly production of biodiesel using supercritical and immobilized enzyme process. Assuming a plant with a production rate of 10,000 tons a year, a PRO II simulator program was used to simulate the product conversion rate and total energy consumption. The product conversion in supercritical process and immobilized enzyme was found to be 91.17% (including 0.9% glycerol) and 93.18% (including 1.0% glycerol) respectively. The result shows that the efficiency of immobilized enzyme process is higher compared to supercritical process but having lower end product purity. From the energy consumption point of view, supercritical process consume about 8.9 MW while immobilized enzyme process consume much lower energy which is 3.9 MW. Consequently, this study certifies that energy consumption of supercritical process is 2.3 times higher than immobilized enzyme process.
Optimization of Process Parameters of Die Slide Injection by Using Taguchi Method
Jeong, Soo-Jin ; Moon, Seong-Joon ; Jeoung, Sun-Kyoung ; Lee, Pyoung-Chan ; Moon, Ju-Ho ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 264~269
DOI : 10.9713/kcer.2012.50.2.264
Die slide injection marvelously reduces the cost and time in processing plastic products because they can simplify the conventional process through eliminating additional process. However, this process must resolve some defects like whitening, resin infiltration, blowhole, resin overflow, etc. In this study, the process parameters of the injection molding are optimized by using the finite element method and Taguchi method. The injection molding analysis is simulated by employing the Moldflow insight 2010 code and the 2nd injection is by adopting the Multi-stage injection code. The process parameters are optimized by using the
orthogonal array and smaller-the-better characteristics of the Taguchi method that was used to produce an airtight container (coolant reservoir tank) from polypropylene (PP) plastic material.rodanwhile, the optimum values are confirmed to be similar in 95% confidence and 5% significance level through analysis of variance (ANOVA). rooreover, new products and old products were compared by mdasuring the dimensional accuracy, resulting in the improvement of dimensional stability more than 5%.
Design and Optimization of Extractive Thermally Coupled Distillation System
Cho, Hoon ; Woo, Daesik ; Choi, Yumi ; Han, Myungwan ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 270~276
DOI : 10.9713/kcer.2012.50.2.270
In this study, thermally coupled distillation system and conventional two-column process were investigated for extractive distillation. The two processes were simulated and optimized using Aspen plus. Objective function for the optimization was energy consumption and optimization results to reduce energy consumption were used to get guidelines for design and operation for the two extractive distillation processes. Comparison of these two processes showed that thermally coupled distillation system provided better energy efficiency and lower capital cost than conventional distillation system.
A Study on Prevention of Accidents of Carbon Monoxide Leak from Gas Boilers
Song, Jaechang ; Kwon, Hweeung ; Lee, Younghee ; Moon, Il ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 277~281
DOI : 10.9713/kcer.2012.50.2.277
This work is concerned with a plan for preventing accidents of CO gas leak from gas boilers, involving the enforcement of installations of both CO alarm system and condensing boilers, and financial support of government grants. If amongst 1,460,000 beneficiaries of basic livelihood security, one million households in use of gas boilers receive 3-year support of 200,000 won, the difference of prices between common and condensing boilers, the government grants would be 2,000 billion won. If 3 million common householders are in 3-year support of 100,000 won, government grants would be 3,000 billion won. Therefore, 3-year grand total of government grants would be 5,000 billion won. Finance for government grants can be purveyed from energy saving; yearly 2,000 billion won of energy saving by enforcing to replace one million existing boilers with condensing boilers, leading to 2 trillion won of energy saving for 10 years. In this way, 6,000 billion won of 3-year grand total of government grants for CO alarm system and condensing boilers can be purveyed. The rest amount would be fundraised for energy savings. We claim that our proposal can make an achievement of more than 50% reduction of CO leak accidents during 10 years.
A Study on Synthesis of Glycidol Based Nonionic Surfactant
Lim, Jong Choo ; Kim, Byeong Jo ; Choi, Kyu Yong ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 282~291
DOI : 10.9713/kcer.2012.50.2.282
The PGLE and PGLE3 nonionic surfactants were synthesized from the reaction between glycidol and lauryl acid and their structures were confirmed by
NMR analysis. The CMCs of PGLE and PGLE3 surfactants were found to be
mol/L respectively and the surface tensions at their CMC conditions were 26.09 mN/m and 28.68 mN/m respectively. Dynamic surface tension measurement has shown that the adsorption rate of surfactant molecules at the interface between air and surfactant solution was found to be relatively fast in both surfactant systems, presumably due to high mobility of surfactant molecules. The contact angles of PGLE and PGLE3 nonionic surfactants were
respectively. Dynamic interfacial tension measurement showed that both surfactant systems reached equilibrium in 20 minutes and the interfacial tensions at equilibrium condition in both systems were 0.42 mN/m and 0.53 mN/m respectively. The PGLE surfactant system has indicated higher foam stability than the PGLE3 surfactant system, which is consistent with surface tension measurement. The phase behavior experiments performed at
in systems containing nonionic surfactant, water, n-hydrocarbon oil and cosurfactant showed a lower phase or oil in water microemulsion in equilibrium with excess oil phase at all conditions investigated during this study.
The Viscosity and Rheology of the Silica Dispersion System with UV Curable Monomers
Ahn, Jae-Beom ; Cho, Bong-Sang ; Yoo, Eui-Sang ; Noh, Si-Tae ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 292~299
DOI : 10.9713/kcer.2012.50.2.292
We made 8 wt% silica dispersion system with fumed silica and photo curable acrylic monomer by beads mill process. These dispersions could be applied in organic/inorganic hybrid coating systems. These dispersions could be applied in organic/inorganic hybrid coating systems. The 4 species of photo curable acrylic monomer which was presence of hydroxyl group, different solubility parameter, and different molecular size were used in the silica dispersions. Stability of polar solvent, isopropyl alcohol, in silica dispersions was investigated. We investigated the stability of silica dispersions by using steady-state and dynamic rheology. As the monomer has hydroxyl group increased in mono and binary monomer silica dispersions, they showed non flocculated stable sol (loss modulus (G")> storage modulus (G')). When polar solvent IPA was added into slightly flocculated silica dispersions, they changed to non flocculated stable sol.
Phase Change of Calcium Carbonate by Adding Polymers
Han, Hyun-Kak ; Jeon, Je-Sung ; Kim, Mi-Sun ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 300~303
DOI : 10.9713/kcer.2012.50.2.300
Phase change of calcium carbontae crystals in crystallization of precipitated calcium carbonate was researched by adding additives such as ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), citric acid (CIT) and pyromellitic amid (PMA). At low temperature
, calcite crystal was made. At high temperature
, aragonite crystal was made without additives. At middle temperature
, Aragonite crystal also made by adding EDTA, DTPA. The crystal growth of Aragonite was retarded by the presence of CIT, PMA and the single phase of calcite was made. It was found that additives were important factors to make the single phase of calcium carbonate.
Size Verification of Small and Large Bubbles in a Bubble Column
Seo, Myung Jae ; Jin, Hae-Ryong ; Lim, Dae Ho ; Lim, Ho ; Kang, Yong ; Jun, Ki-Won ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 304~309
DOI : 10.9713/kcer.2012.50.2.304
Size verification of small and large bubbles in a bubble column was investigated by employing the dynamic gas disengagement (DGD) method and dual electrical resistivity probe (DRP) method, simultancously. The holdups of large and small bubbles in the bubble column in a given operating condition were obtained by means of the DGD method by measuring the pressure drop variation in the column with a variation of time after stopping the gas input into the column. The size and frequency of bubbles were measured by the DRP method in the same operating condition, from which the bubble holdup of each range of size was obtained. The verification of size in determining the large or small bubbles was decided by comparing the holdups of large or small bubbles measured by the DGD method with that measured by the DRP method. Filtered compressed air and tap water were used as a gas and a continuous liquid medium. The diameter and height of the bubble column were 0.102 m and 1.5 m, respectively. The demarcation size between the large and the small bubbles in the bubble column was 4.0~5.0 mm; the demarcation size was about 5.0 mm when the gas velocity was in the relatively low range, but about 4.0 mm when the gas velocity was in the relatively high range, within this experimental conditions.
Chromaticity Improvement of PEG Waste from Wire Sawing of Silicon Ingot
Cho, Yun-Kyeong ; Jung, Kyeong-Youl ; Sim, Min-Seok ; Lee, Gi-Ho ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 310~316
DOI : 10.9713/kcer.2012.50.2.310
The chromaticity of polyethylene glycol (PEG) generated from the recyling of a silicone slurry waste was improved by using activated carbon powder and a carbon filter. The color change of the PEG waste was investigated by changing the amount of adsorbent, adsorption time and temperature. The surface area of activated carbon did not have a significant impact on improving the color of the PEG waste. According to the results for the APHA color variation of the PEG waste changing the amount of the carbon adsorbent, the optimal usage to achieve the low APHA value was 100~150 mg-C/g-PEG. From the investigatnion on the effect of the adsorption temperature range from
, it was found that the optimal temperatures were
in terms of achieving the lowest APHA value. The variation of the APHA color was investigated by changing the operation condition of the activated carbon filters. The use of ACF was a good way to enhance the chromaticity of the PEG waste. As a result, the APHA value of the PEG waste (APHA=53 at the initial waste) was reduced to be 10 through the ACF purification. It was also confirmed that the performance of the used carbon adsorbent can be recovered by the washing with purified water.
Experimental Analysis on Filtration-Permeation: Influence of the Type and Sheets of Filter Media, and Filtration Pressure
Yim, Sung-Sam ; Song, Yun-Min ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 317~327
DOI : 10.9713/kcer.2012.50.2.317
The average specific cake resistance, the most important indicator for cake filtration and solid-liquid separation, is measured by filtration experiment. But the exact value is difficult to measure because of the other influences such as sedimentation during filtration. This study, a little more stable method named filtration-permeation is proposed for measuring average specific cake resistance. The filtration-permeation is composed of permeation of particle eliminated water through pre-formed cake by filtration. Using 1 wt% calcium carbonate suspension, the filtration-permeation experiments were performed for 8 kinds of filter media at the conditions of 0.5 atm and 0.2 atm, 1 and 3 sheets of filter media. At each specific condition, three to five times filtration-permeation were accomplished. As a result, stable permeation speed is measured. According to this experimental result, the characteristics of permeation and the effect of sedimentation are analyzed with Ruth's equation. The one way analysis of variance (one way ANOVA) is applied to the average specific cake resistances of filtration and permeation obtained with the selected three kinds of filter media. The average specific cake resistances between 0.5 atm and 0.2 atm by filtration do not distinguished, but those by permeation is perfectly distinguished. The experimental results during permeation have a very narrow distribution than that measured during filtration. The analysis of filtration experiments, it was verified that the resistance of filter medium by traditional method is of no significance. Finally, the migration of small particles through the medium composed of fiber glass at low pressure was studied.
CFD Simulation for Mixture Characteristic of DME-Propane Liquified Fuels
Kim, Cha-Hwan ; Chun, Seuk-Hoon ; Shin, Dong-Woo ; Kim, Lae-Hyun ; Lee, Hyun-Chan ; Baek, Young-Soon ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 328~333
DOI : 10.9713/kcer.2012.50.2.328
In this study, CFD simulation was performed with commercial CFD code FLUENT for the 3D mixing tank model (1 m in a diameter and 2.5 m in a height) of DME-Propane liquified fuels. Initial condition set-up with existence of DME 146 l at the upper side of mixing tank and Propane 770 l at the lower side of mixing tank. Characteristics of mixture and fluid flow were observed for 34 hours simulation. Two liquid fuel were uniformly mixed within range of 3 mol% after 24 hours, and range of 1 mol% after 34 hours. The simulation result following 4 hours was verified with KOGAS experimental data.
The Role of p
in the Unified Theory on Solid-Liquid Separation: Especially on the Cake Thickness at Hindered Sedimentation, Cake Filtration and Expression
Yim, Sung-Sam ; Song, Yun-Min ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 334~342
DOI : 10.9713/kcer.2012.50.2.334
To know the role of 'the solid compressive pressure to the first solid layer of a cake,
' in the 'unified theory on solid-liquid separation', we analyzed extremely compressible cake formed with floc for the following three operations with our new concepts. First, the role of
was studied in calculating the sediment thickness of floc, and in calculating the cake thickness in cake filtration performed with floc sediment. Second, we calculated the expression procedure using
. Finally, the influence of
on cake thickness in hindered sedimentation, and on the calculation of the procedure of hindered sedimentation
was verified. Thus the possibility of application of 'unified theory on solid-liquid separation' and the importance of
was verified. Through these processes, new theoretical definitions of the cake filtration, expression and hindered sedimentation was established.
Decomposition Characteristics of Cyano-compounds in Non-thermal Packed-Bed-Plasma-Reactor
Ryu, Sam-Gon ; Park, Myung-Kyu ; Lee, Hae-Wan ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 343~347
DOI : 10.9713/kcer.2012.50.2.343
The decomposition behaviors of gaseous cyanides in non-thermal plasma-catalyst hybrid reactor have been investigated with the variation of discharge power, influent concentration of cyanide, humidity of air carrier and packed materials in the reactor. Destruction of cyanides by plasma only process was very difficult compared to that of trichloroethylene. But the destruction efficiencies of cyanides were dramatically improved through packing alumina or Pt/alumina bead in the plasma discharge region. From the results, it could be assumed that thermal catalytic effect is involved simultaneously with plasma in the reaction of cyanides destruction on the alumina or Pt/alumina packed plasma reactor.
Analysis of Amine Absorbents Volatility Based on the Chemical Structure
Lee, Kyung Ja ; Lee, Ji Hyun ; Kwak, No Sang ; Lee, In Young ; Kim, Jun Han ; Eom, Yong Seok ; Jang, Kyung Ryoung ; Shim, Jae Goo ; Lee, Yongtaek ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 348~352
DOI : 10.9713/kcer.2012.50.2.348
Amine volatility occurring on the
capture process may result in significant economic losses and environmental impact. In this study, using an volatility measurement apparatus, we measured a amine volatility of various amines including MEA(Monoethanolamine), MDEA(N-Methyldiethanolamine), Pz(Piperazine), AMP(2-Amino-2-methyl-1-propanol), 2-MP(2-Methylpiperazine), DGA(Diglycolamine). For the quantitative analysis of volatility, we analyzed the effects of temperature and
loading using an gas chromatography analysis. The result shows that the amine volatility was increased by increasing Henry's constant(MDEA
Determination Method of Hydrocarbon Compounds in DME-LPG Blending Fuels by Gas Chromatography with Deans Switching
Youn, Ju Min ; Park, Cheon Kyu ; Yim, Eui Soon ; Jung, Choong Sub ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 353~357
DOI : 10.9713/kcer.2012.50.2.353
The new qualitative and quantitative analytical method for hydrocarbon compounds in DME-LPG blending fuel, mixing dimethyl ether (DME) with liquefied petroleum gas (LPG), by using gas chromatography (GC) was investigated. It is difficult to analyze all components of DME-LPG blending fuel by using single column in GC due to consisting of the non-polar LPG and the polar DME which is oxygen-containing compound. Therefore, it has been introduced the Deans switching system, which are useful for analyzing mixtures of a very different nature and/or target analytes in very complex matrix. This technique is to control the pressure between two columns and to selectively change the path of effluent flows to either one of two columns. As a result, we found that DME and LPG can be completely separated at the different columns and the determination of all hydrocarbon compounds in DME-LPG blending fuel can be achieved to this method qualitatively and quantitatively during the operation of one injection. In addition, this method can be applied to the determination of trace components of by-product, such as methanol, methyl formate and ethyl methyl ether, which will be derived from DME synthesis process.
Kinetic Study of the Fischer-Tropsch Synthesis and Water Gas Shift Reactions over a Precipitated Iron Catalyst
Yang, Jung-Il ; Chun, Dong Hyun ; Park, Ji Chan ; Jung, Heon ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 358~364
DOI : 10.9713/kcer.2012.50.2.358
The kinetics of the Fischer-Tropsch synthesis and water gas shift reactions over a precipitated iron catalyst were studied in a 5 channel fixed-bed reactor. Experimental conditions were changed as follows: synthesis gas
/CO feed ratios of 0.5~2, reactants flow rate of 60~80 ml/min, and reaction temperature of
at a constant pressure of 1.5 MPa. The reaction rate of Fischer-Tropsch synthesis was calculated from Eley-Rideal mechanism in which the rate-determining step was the formation of the monomer species (methylene) by hydrogenation of associatively adsorbed CO. Whereas water gas shift reaction rate was determined by the formation of a formate intermediate species as the rate-determining step. As a result, the reaction rates of Fischer-Tropsch synthesis for the hydrocarbon formation and water gas shift for the
production were in good agreement with the experimental values, respectively. Therefore, the reaction rates (
) derived from the reaction mechanisms showed good agreement both with experimental values and with some kinetic models from literature.
Performance and Economic Analysis of Domestic Supercritical Coal-Fired Power Plant with Post-Combustion CO
Lee, Ji-Hyun ; Kwak, No-Sang ; Lee, In-Young ; Jang, Kyung-Ryoung ; Shim, Jae-Goo ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 365~370
DOI : 10.9713/kcer.2012.50.2.365
In this study, Economic analysis of supercritical coal-fired power plant with
capture process was performed. For this purpose, chemical absorption method using amine solvent, which is commercially available and most suitable for existing thermal power plant, was studied. For the evaluation of the economic analysis of coal-fired power plant with post-combustion
capture process in Korea, energy penalty after
capture was calculated using the power equivalent factor suggested by Bolland et al. And the overnight cost of power plant (or cost of plant construction) and the operation cost reported by the IEA (International Energy Agency) were used. Based on chemical absorption method using a amine solvent and 3.31 GJ/
as a regeneration energy in the stripper, the net power efficiency was reduced from 41.0% (without
capture) to 31.6% (with
capture) and the levelized cost of electricity was increased from 45.5 USD/MWh (Reference case, without
capture) to 73.9 USD/MWh (With
capture) and the cost of
avoided was estimated as 41.3 USD/
Synthesis and Characterization of Epoxy Silane-modified Silica/Polyurethane-urea Nanocomposite Films
Joo, Jin ; Kim, Hyeon Seok ; Kim, Jin Tae ; Yoo, Hye Jin ; Lee, Jae Ryung ; Cheong, In Woo ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 371~378
DOI : 10.9713/kcer.2012.50.2.371
Hydrophilic silica nanoparticles (SNPs) were treated by using 3-glycidoxypropyltrimethoxy silane (GPTMS) and then they were blended with polyurethane-urea (PUU) emulsions to obtain SNPs/PUU nanocomposite films. Thermo-mechanical properties of the nanocomposite films were investigated by varying the grafted amount of GPTMS onto SNPs and the contents of SNPs in the PUU matrix. The thermo-mechanical properties of the nanocomposite films were also compared in terms of the dispersibility of SNPs in the PUU matrix and thermal curing of the GPTMS-grafted SNPs. The maximum amount of grafted GPTMS was
, and which covered ca. 53% of the total SNP surface area.
CP/MAS NMR analyses with the deconvolution of peaks revealed the details of polycondensation degree and patterns of GPTMS in the surface modification of SNPs. The surface modification did not significantly affect colloidal stability of the SNPs in aqueous medium; however, the hydrophobic modification of SNPs offered a favorable effect on the dispersibility of SNPs in the PUU matrix as well as better thermal stability. XRD patterns revealed that GPTMS-grafted SNPs broadened the reduced the characteristic peak of polyol in PUU matrix. The composite films became rigid and less flexible as the SNP content increased from 5 wt.% to 20 wt.%. Particularly, Young's modulus and tensile modulus significantly increased after the thermal curing reaction of the epoxy groups in the SNPs.
Surface Properties of Glutathione Layer Formed on Gold Surfaces
Park, Jin-Won ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 379~384
DOI : 10.9713/kcer.2012.50.2.379
It is investigated that that the physical properties of Glutathione layer formed on gold surfaces may make an effect on the distribution of either gold particle adsorbed to the
surface or vice versa with the adjustment of the electrostatic interactions. For the investigation, the atomic force microscope (AFM) was used to measure the surface forces between the surfaces as a function of the salt concentration and pH value. With the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the forces were quantitatively analyzed to acquire the surface potential and charge density of the surfaces for each salt concentration and each pH value. The surface potential and charge density dependence on the salt concentration was described with the law of mass action, and the pH dependence was explained with the ionizable groups on the surface. The salt concentration dependence of the surface properties, found from the measurement at pH 8 and 11, was consistent with the prediction from the law. It was found that the Glutathione layer had higher values for the surface charge densities and potentials than the titanium dioxide surfaces at pH 8 and 11, which may be attributed to the ionized-functional-groups of the Glutathione layer.
Torrefaction Characteristics of Wood Chip for the Production of High Energy Density Wood Pellet
Lee, Jae-Won ; Kim, Young-Hun ; Lee, Soo-Min ; Lee, Hyoung-Woo ;
Korean Chemical Engineering Research, volume 50, issue 2, 2012, Pages 385~389
DOI : 10.9713/kcer.2012.50.2.385
In this study, torrefaction of mixed softwood chips under anoxic condition was performed to improve energy density and maintain consistent quality of biomass. Characteristics of torrefied biomass depending on reaction time (30 min) and temperature (240, 260,
) were investigated. Torrefaction of mixed softwood chips significantly improved the heating value compared to that of untreated biomass. As the torrefaction temperature was increased, the carbon content of torrefied biomass increased from 46.55 to 55.73%, while its hydrogen and oxygen contents decreased from 6.00 to 5.87% and from 30.55 to 27.21%, respectively. Most of hemicelluloses and volatile compounds were removed during torrefaction. The highest heating value was 5132 kcal/kg when torrefaction was performed at
for 30 min. It implied that the heating value increased by 13% compared to that of original biomass. However, the condition of effective torrefaction was at
for 30 min when weight loss and energy yield was considered.