• Journal of Mechanical Science and Technology
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• v.16 no.1
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• pp.102-108
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• 2002

Numerical simulations of 1, 2 dichloroethane(EDC) pyrolyisis are conducted to understand the process in the production of the vinyl chloride monomer (VCM) and by-products. A chemical kinetic mechanism Is developed, with the adopted scheme involving 44 gas-phase species and 260 elementary forward and backward reactions. Detailed sensitivity analyses and the rates of production analysis are performed on each of the reactions and the various species, respectively. The concentrations of EDC, VCM, and HCI predicted by this mechanism are in good agreement with those deduced from experiments of commercial and laboratory scale. The mechanism is found to accurately predict the EDC yield an(1 the production of by-products by varying the ranges of pyrolysis temperature, residence time, and pressure which impact on the pyrolysis of 1, 2 dichloroethane. The influence of reactions related to H atom on the relative sensitivity of EDC becomes important as the residence time increases. The pyrolysis of EDC mainly occurs through C$_2$H$_4$Cl$_2$+Cl=CH$_2$CICHI+HCI.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.235-237
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• 2012

Geodae-Uksae 1 is a variety of Miscanthus sacchariflorus recently discovered in Korea. It is being mass-cultivated for use as energy crop due to its superior productivity, as high as 30 ton/ha/yr for the dry mass. This study investigates the method of producing biochar and bio-oil from the crop using slow pyrolysis. Especially, the study focused on assessing the biochar properties for its application to soil to improve soil quality and sequestrate carbon. Using an electrically heated packed bed reactor, the products of slow pyrolysis from Geodae-Uksae 1 were produced over a temperature range of $300-700^{\circ}C$ with a heating rate of $10^{\circ}C/min$. The biochar, condensable vapor (bio-oil) and residual gases were characterized for the physical and chemical properties. It was concluded that the ideal temperature for pyrolysis to produce biochar is $500^{\circ}C$.

• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.172-180
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• 2006

A novel pyrolysis-melting incineration system of reduced scale (30 kg/hr) is and constructed in Korea Institute of Industrial Technology. The incineration process is composed of three parts: pyrolysis, gas combustion and ash melting processes. For each unit process, experimental and numerical approaches including reduced-scale cold/hot flow tests have been conducted to find optimal design and operating conditions. This paper presents major results of these approaches with brief descriptions on the pilot-scale incinerator (200 kg/hr) under construction and future research works.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.331-335
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• 2009

A novel multi-staged waste pyrolysis & gasification system of pilot scale (~1 ton/day) is designed and constructed in Korea Institute of Industrial Technology. The pyrolysis & gasification system is composed of pyrolysis & gasification system, syngas reformer, syngas cleaning system, gas engine power generation system and co-combustion system. For each unit process, experimental approaches have been conducted to find optimal design and operating conditions. As a result, We can produce syngas with a calorific value of ~4000 kcal/$Nm^3$ and cold gas efficiency of the system is more than 55 % in case of waste plastic and oxygen as a gasifying agent.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.5
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• pp.577-583
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• 2017

A series of microwave waste tire pyrolysis experiments were conducted using a lab-scale batch reactor to delineate the effects of microwave ouput power on the pyrolysis behavior of waste tire. As results of experiments, it was found that as the microwave output power was increased from 1.22 kW/kg to 2.26 kW/kg, the reaction temperature and oil yield increased significantly and the required time and microwave power consumption decreased remarkably, respectively. With increased power consumption, the content of the fixed carbon of pyrolysis residue increased.

• The Korean Journal of Ceramics
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• v.3 no.3
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• pp.191-194
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• 1997

Epitaxial Pb(Zr, Ti)O3(PZT) thin films were prepared on MgO(100) substrates by dipping-pyrolysis (DP) process using metal naphthenates as starting materials, and effects of pyrolysis and final heat-treatment conditions on the film's orientation were investigated. Solid-state epitaxial growth of PZT proceeds at lower temperature around 650℃ from the precursor pyrolyzed at 350 and 500℃. The in-plane alignment of the PZT films depends not only on the final heat-treatment temperature but on the pyrolysis conditions; the films, pyrolyzed at a higher temperature for a short time, i.e., at 500℃ for 10 min, exhibited stronger orientation after the same final heat treatment at 650°∼750℃. The PZT films with the strongest orientation were prepared by pyrolysis under the above conditions followed by final heat treatment at 750℃.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.106-114
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• 1963

The products from polymer pyrolysis at $450^{\circ}$ are cooled with ice, then liquid and gaseous portions are analysed by gas chromatography. Di-2-ethyl hexyl sebacate column, silicone oil column, silica gel column and tetraethyleneglycol dimethylether column, which was most effective for the separation of hydrocarbon gases, are used. Identification of isomers could be secured more effectively by gas chromatography than mass spectrometry. Elucidation of the mechanism for thermal decomposition of polymers could be done through the identification of pyrolysis products. Although more extensive work is needed, some patterns of polymer pyrolysis are discussed.

• New & Renewable Energy
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• v.5 no.4
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• pp.52-58
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• 2009

Upgrading of pyrolysis wax oil using HZSM-5 catalyst has been conducted in a continuous fixed bed reactor at $450^{\circ}C$, 1hour, LHSV 3.5/h. The catalytic degradation was studied with a function of catalyst amount and reaction temperature. The raw pyrolysis wax oil shows relatively high boiling point distribution ranging from around $300^{\circ}C$ to $550^{\circ}C$, which has considerably higher boiling point distribution than that of commercial diesel. The catalytic degradation using HZSM-5 catalyst shows the high conversion of pyrolysis wax oil to light hydrocarbons. The liquid product obtained shows high gasoline range fraction as around 90% fraction and considerably high aromatic fraction in liquid product. Here, the experimental variable such as catalyst amount and reaction temperature was influenced on the product distribution.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2480-2486
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• 2018

Mesoporous $TiO_2$ microspheres were prepared by spray pyrolysis for photocatalysis. Post modification of $TiO_2$ by heat treatment was performed to optimize its photocatalytic performance. First, spherical $TiO_2$ particles with mesoporous structure were synthesized at pyrolysis temperatures of 500, 600, and $700^{\circ}C$. After characterization by XRD, SEM, and $N_2$ adsorption, a sample prepared at $500^{\circ}C$ was found to possess desirable properties for photocatalytic performance through post-modification. In methylene blue degradation, mesoporous $TiO_2$ microspheres synthesized at $500^{\circ}C$ outperformed other microspheres. Furthermore, samples obtained by spray pyrolysis at $500^{\circ}C$ were calcined at various temperatures as a post-modification process. The sample calcined at $350^{\circ}C$ showed improved photocatalytic activity due to optimal anatase crystallinity and surface area.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.126-129
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• 2007

The particle formation using pyrolysis has many advantages over other particle manufacturing techniques. The particles by pyrolysis have relatively uniform size and chemical composition. Also, we can easily produce high purity particles. Thus, we studied the formation of silicon particles by pyrolysis of 50% $SiH_4$ gas diluted in Ar gas. A pyrolysis furnace was used for the thermal decomposition of $SiH_4$ gas at $800^{\circ}C$ and atmospheric pressure. The aerosol flow from furnace is separated into two ways. The one is to the Scanning Mobility Particle Sizer (SMPS) for particle size distribution measurement and the other is to the particle deposition system. The produced silicon particles are deposited on the wafer in the deposition chamber. SEM measurement was used to compare the particle size distribution results from the SMPS. Depending on the experimental conditions, particles of high concentration in the $30\sim80$ nm size range were generated.