• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.1951-1955
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• 2014

Catalytic pyrolysis of Geodae-Uksae 1, a kind of miscanthus found in Korea, was carried out over mesoporous MCM-48 catalysts. For rapid product analysis and catalyst evaluation, pyrolysis-gas chromatography/mass spectrometry was used. X-ray diffraction, nitrogen sorption, pyridine adsorbed Fourier transform infrared, and NH3 temperature programmed desorption were utilized to analyze the properties of the catalysts. Compared to non-catalytic reaction, catalytic upgrading over mesoporous Al-MCM-48 catalysts produced a higher-quality bio-oil with a high stability and low oxygen content. Al-MCM-48 exhibited higher deoxygenation ability than Si-MCM-48 due to its higher acidity.

• Applied Chemistry for Engineering
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• v.30 no.6
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• pp.707-711
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• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• Elastomers and Composites
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• v.55 no.4
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• pp.257-262
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• 2020

Vehicle wiper blades are typically treated with chlorine to lower their friction coefficient with the windshield surface. In this study, a chlorinated, natural rubber (NR) vehicle wiper blade was characterized using a pyrolytic technique. Unchlorinated and chlorinated wiper blades were pyrolyzed and the pyrolysis products were analyzed using gas chromatography/mass spectrometry (GC/MS). Besides isoprene and dipentene, the other principal pyrolysis products such as 1,5,8-p-menthatriene (MTT) and p,α-dimethylstyrene (DMS) were observed. The MTT and DMS ratios did not vary for the chlorinated nor unchlorinated samples when the entire rubber lip of the wiper blade was pyrolyzed. However, when only the lip surface of the wiper blade rubber was pyrolyzed (via scratching with a knife) the relative ratios of the chlorinated sample were much greater than those of the unchlorinated sample. As MTT is produced from the conjugated backbone of chlorinated NR that forms through HCl elimination during initial pyrolysis, and DMS is generated by the dehydrogenation of MTT, these two products could be used as markers for detecting chlorinated NR.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.190-190
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• 2003

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.4
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• pp.57-63
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• 2008

The characteristics of the bio-oil produced by the pyrolysis process with pig feces was investigated in this paper. The continuous auger-type reactor produced bio-oil was maintained at the temperature range of 400 to $600^{\circ}C$, which was higher than a typical that in a conventional pyrolysis system. The pig feces was used as the feedstock. The bio-oil and its compositions were characterized by water analysis, heating values, elemental analysis, bio-oil compounds, by Gas Chromatography/Mass Spectrometry (GC/MS), and functional group by $^1H$ NMR spectroscopy. It was found that the maximum bio-oil yields of 21% w.t. was achieved at $550^{\circ}C$. This result suggested that this auger reactor might be a potential technology for livestock waste treatment to produce bio-oil because it is able to be improved to reach higher efficiency of bio-oil production in further study. The pyrolysis system reported herein had low heat transfer into the feedstock in the auger reactor so that it needs improve the heat conduction rate of the system in further study.

• Journal of Conservation Science
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• v.36 no.2
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• pp.103-111
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• 2020

To compare the cleaning effect of solvents such as water and ethanol used to clean lacquer relics, the components extracted with various solvents were analyzed. A freshly dried lacquer sample and a lacquer sample exposed to ultraviolet radiation for 24 days were treated with water, ethanol, acetone, and hexane, and the dissolved material was detected by pyrolysis-gas chromatography-mass spectrometry. The amount extracted was significantly higher in acetone and ethanol than in hexane, a nonpolar solvent. Water, a highly polar solvent, was relatively efficient for extracting low-molecular-weight materials. After experiencing 24 days of ultraviolet radiation, the lacquer exhibited a significant increase of extracted materials compared with the nonexposed one. This may be due to the degradation of the urushiol chain in the form of polymers, resulting in the formation of low-molecular-weight polar substances, including dicarboxylic acids. In addition to the deterioration status of lacquer relics, such solvent extraction properties will be a crucial consideration in selecting the appropriate cleaning solvent.

• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.14-20
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• 2018

Purpose: The purpose of this study was to investigate the performance of a vacuum pyrolysis system, to analyze bio-oil characteristics, and to examine the applicability for farm-scale capacity. Methods: The biomass was pyrolyzed at 450, 480, and $490^{\circ}C$ on an electric heat plate in a vacuum reactor. The waste heat from the heat exchanger of the reactor was recycled to evaporate water from the bio-oil. The chemical composition of the bio-oil was analyzed by gas chromatography-mass spectrometry (GC-MS). Results: According to the analysis, the moisture content (MC) in the bio-oil was approximately 9%, the high heating value (HHV) was approximately 26 MJ/kg, and 29 compounds were identified. These 29 compounds consisted of six series of carbohydrates, 17 series of lignins, and six series of resins. Conclusions: Owing to low water content and the oxygen content, the HHV of the bio-oil produced from the vacuum reactor was higher by about 6 MJ/kg than that of the bio-oil produced from a fluidized bed reactor.

• The Korean Journal of Community Living Science
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• v.24 no.2
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• pp.243-249
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• 2013

Identification of coating film species from ancient coating materials is needed to maintaine their surfaces without loss of their original beauty for a long time and understand the historical background of manufacturing techniques. A pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was applied to identify the origine of films in ancient coating materials. The pyrolysis products, which reflect the source from which they originate were detected distinctively at $500^{\circ}C$. This is a rapid technique that does not require large amounts of sample or any sample preparation. Sesquiterpenes are a class of terpenes that consist of three isoprene units were identified as cadienes, selinenes, cubebenes from the raw material of dendropanax morbifera. On the other hand, alkanes(tetra~heptadecanes), alkenes (tri~heptadecenes), allkyphenols, catechols and fatty acids were detected from the raw material of the lacquer film. Based on these results, the origine of historic coatings artifacts was identified using py-GC/MS by comparison with their pyrolysis products.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.118-124
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• 2007

GRLs(Guidance Residue Levels) of agricultural chemicals for tobacco are recommended by the CORESTA Agro-Chemical Advisory Committee guide. In the GRLs list, organochlorine group is one of pesticides commonly used on tobacco cultivation. In this model study, the quantitative correlation in the transfer rate of pesticide residue into tobacco smoke by spiking of organochlorine pesticides to cigarette and pyrolysates were investigated. The spiking concentration referred to the range of GRLs list and the organochlorine pesticides in mainstream smoke were analyzed by GC-MS. For the understanding of the composition variation versus temperature, the behavior of pesticides was investigated by pyrolysis-gas chromatography-mass spectrometry(Py-GC-MS). In this study, the transfer rate of pesticide residue into tobacco smoke at four different spiking concentration and the composition of pyrolysates were analyzed differently. At $10\;{\mu}g/cig$ spiking concentrations, the organochlorine pesticides were transferred into tobacco smoke in $0.02\;{\sim}\;10.19\;%$ each of component and the most of pesticides were pyrolyzed during smoking. It was found that the decomposition compounds from organochlorine pesticides were mainly composed of oxygenated and nitrogenous compounds. This study could estimate that the transfer rate of pesticides into tobacco smoke is very small amount.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.513-518
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• 2005

The co-pyrolysis characteristics of poly(vinyl chloride) (PVC) and polystyrene (PS) mixtures with ZnO have been studied by thermogravimetry (TG) and gas chromatograph-mass spectrometry (GC-MS) under various mixing ratios and reaction temperatures. From this work, it was found that the yield of liquid products increased as PS in mixtures increased, whereas that of gaseous products decreased. And as ZnO in mixtures increased, the yields of gaseous products and HCI decreased. The optimal reaction temperature for the maximum yield of liquids products and the control of HCI gas was $500^{\circ}C$.