• Journal of the Korean Applied Science and Technology
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• v.23 no.4
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• pp.307-318
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• 2006

The pyrolysis of high density polyethylene(HDPE) and low density polyethylene(LDPE) was carried out at temperature between 425 and $500^{\circ}C$ from 35 to 80 minutes. The liquid products formed during pyrolysis were classified into gasoline, kerosene, gas oil and wax according to the petroleum product quality standard of Korea Petroleum Quality Inspection Institute. The conversion and yield of liquid products for HDPE pyrolysis increased continuously according to pyrolysis temperature and pyrolysis time. The influence of pyrolysis temperature was more severe than pyrolysis time for the conversion of HDPE. For example, the liquid products of HDPE pyrolysis at $450^{\circ}C$ for 65 minutes were ca. 30wt.% gas oil, 15wt.% wax, 14wt.% kerosene and 11wt.% gasoline. The increase of pyrolysis temperature up to $500^{\circ}C$ showed the increase of wax product and the decrease of kerosene. The conversion and yield of liquid products for LDPE pyrolysis continuously increased according to pyrolysis temperature and pyrolysis time, similar to HDPE pyrolysis. The liquid products of LDPE pyrolysis at $450^{\circ}C$ for 65 minutes were ca. 27wt.% gas oil, 18wt.% wax, 16wt.% kerosene and 13wt.% gasoline.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.486-497
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• 2019

The non-isothermal and isothermal pyrolysis properties of H lignin and P lignin extracted from different biorefinery processes (such as supercritical water hydrolysis and fast pyrolysis) were studied using thermogravimetry analysis (TGA) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). The lignins were characterized by ultimate/proximate analysis, FT-IR and GPC. Based on the thermogravimetry (TG) and derivative thermogravimetry (DTG) curves, the thermal decomposition stages were obtained and the pyrolysis products were analyzed at each thermal decomposition stage of non-isothermal pyrolysis. The isothermal pyrolysis of lignins was also carried out at 400, 500, and $600^{\circ}C$ to investigate the pyrolysis product distribution at each temperature. In non-isothermal pyrolysis, P lignin recovered from a fast pyrolysis process started to decompose and produced pyrolysis products at a lower temperature than H lignin recovered from a supercritical water hydrolysis process. In isothermal pyrolysis, guaiacyl and syringyl type were the major pyrolysis products at every temperature, while the amounts of p-hydroxyphenyl type and aromatic hydrocarbons increased with the pyrolysis temperature.

• Macromolecular Research
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• v.14 no.3
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• pp.354-358
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• 2006

Polybutadiene (BR) was pyrolyzed at $540-860^{\circ}C$ and the effect of pyrolysis temperature on variations in the relative abundance of the major pyrolysis products (C4-, C5-, C6-, C7-, and C8-species) was investigated. Formation of the C4-, C5-, C6-, and C7-species competed with that of the C8-species. Relative intensity of the C8-species decreased with increasing pyrolysis temperature, while that of the C5-, C6-, and C7-species increased. Pyrolysis paths were became more complicated with increasing pyrolysis temperature. We suggested the operation of double bond migration and succeeding rearrangements for the formation of the C5- and C7-species and various rearrangements, including a double bond, for the formation of the C6-species at high temperature. The activation energies for the pyrolysis product ratios of(C5+C6+C7)/C4 and C8/C4 were used to explain the competition reactions to form the pyrolysis products.

• Journal of Environmental Health Sciences
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• v.16 no.2
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• pp.89-95
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• 1990

This study was investigated to the energy recovery by the pyrolysis of waste tyre. the pyrolysis of the waste tyre was made by using the pyrolysis chamber for the gasification and the combustion chamber for the combustion of the pyrolysis gas. In batch system, the amount of waste tyre was put 150kg in the pyrolysis chamber and the proper air flow rate for the stable production of the pyrolysis gas was 0.95Nm$^{3}$ /min. the production time of the pyrolysis gas was stable above 210minutes, and the stable production rate was above 3.8Nm$^{3}$ /min. The production temperature of pyrolysis gas was 170$^{\circ}$C and combustion temperature of pyrolysis gas was 1,000$^{\circ}$C. The combustible component of washing gas in pyrolysis gas of waste tyre was CO, CH$_{4}$, $C_{2}H_{6}$ and $C_{3}H_{8}$, and total amount was 22.7%. Heat value of condensed material was 9,804Kcal/kg. The average concentration of air pollutants between cyclone and scrubber was CO 420.4ppm, SO$_{x}$ 349.8ppm. NO$_{x}$ 68.Sppm, HCl 24.4ppm and Dust 240.0g / Nm$^{3}$, respectively.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.2
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• pp.223-233
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• 2020

Fast pyrolysis is one of the most promising technologies for converting biomass to liquid fuels. Pyrolysis bio-oil can replace petroleum-based fuels used in various thermal conversion devices. However, pyrolysis bio-oil is completely different from petroleum fuels. Therefore, in order to successfully use pyrolysis bio-oil, it is necessary to understand the fuel characteristics of pyrolysis bio-oil. This paper focuses on fuel characteristics and upgrading methods of pyrolysis bio-oil and discusses how these fuel characteristics can be applied to the use of pyrolysis bio-oils. In addition, the fuel quality standards of fast pyrolysis bio-oil were examined.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.103-110
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• 2003

This study was conducted to investigate the pyrolysis products of ι-menthol by Curie-Point pyrolysis. The pyrolysis of ι-menthol was performed at 16$0^{\circ}C$, 42$0^{\circ}C$, $650^{\circ}C$, and 92$0^{\circ}C$ by Curie-Point Pyrolyzer and their pyrolysis products were analyzed by GC/MSD. In addition, tobacco leaves added ι-menthol were pyrolyzed at the same condition in case of ι-menthol. The beginning temperature for pyrolysis formation was in the vicinity of 42$0^{\circ}C$ and the major components of the pyrolysis products identified were iso-menthol, 2-menthene, menthomenthene, and menthone. The amount of these components was increased by increasing temperature and the hydrocarbons such as hexadecene and pentadecene formed by ring cleavage were generated at 92$0^{\circ}C$. The yield of ι-menthol in pyrolysis of tobacco leaves was decreased as the temperature of pyrolysis was raised and the pyrolysis products of ι-menthol weren't identified in the pyrolysis of tobacco leaves. Also, to analyze the weight decrease, ι-menthol was analysed by thermal analyzer(TA), and then the weight decrease of ι-menthol was occurred in the vicinity of 18$0^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.19 no.4
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• pp.258-264
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• 2002

Pyrolysis of polypropylene(PP) Was performed to find the effects of the pyrolysis temperature(425, 450, 475 and $500^{\circ}C$) and the pyrolysis time(35, 50 and 65minutes), respectively. Conversion and liquid yield obtained during PP pyrolysis continuously increased with the pyrolysis temperature( up to $500^{\circ}C$) and the pyrolysis time(up to 65minutes), especially these were more sensitive to the pyrolysis time at $425^{\circ}C$ than other pyrolysis temperatures. Each liquid product formed during the pyrolysis was classified into gasoline, kerosene, light oil and wax according to the distillation temperature based on the petroleum product quality standard of Korea Petroleum Quality Inspection Institute. The liquid products of PP pyrolysis up to $450^{\circ}C$ were almost same fractions($26{\pm}3$wt.% gasoline, $20{\pm}2$wt.% kerosene and $23{\pm}2$wt.% light oil) except wax($3{\sim}13$wt.%). On the other hand, the pyrolysis of PP from $475^{\circ}C$ to $500^{\circ}C$ produced $26{\pm}3$wt.% wax, $24{\pm}1$wt.% gasoline, $18{\pm}1$wt.% kerosene and $16{\pm}1$wt.% light oil. After all, the main liquid product changed from gasoline to wax with increasing pyrolysis temperature.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.122-127
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• 1963

Pyrolysis fo polyethylene and polypropylene has been studied in order to clarify the mechanism of chain scission and effect of oxygen on degradation. Rate of weight decrease was measured under nitrogen and air atmosphere at constant temperature for the samples of high density polyethylene, low density polyethylene and isotactic polypropylene, and then gaseous hydrocarbons produced from pyrolysis were analysed by gas chromatography. Although there is little substantial difference between composition of hydrocarbon gases from pyrolysis of high density polyethylene and low density polyethylene except some difference in quantity of total gas produced, gas composition from polypropylene pyrolysis differs from that of polyethylene pyrolysis. Gases from pyrolysis under air contain much more unsaturated hydrocarbons than those from pyrolysis under inert gas.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.1
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• pp.31-39
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• 2005

This study was conducted to evaluate the characterization of the pyrolysis products of propylene glycol(PG) and glycerine alone and together with tobacco. The weight change of the samples during the pyrolysis was measured by a thermal analyzer(STD-2960). The pyrolysis products were determined by GC/MS after pyrolysis using a curie-point pyrolyzer(CPP, $220^{\circ}C,\;420^{\circ}C,\;650^{\circ}C,\;and\;920^{\circ}C$) and a double-shot pyrolyzer(DSP, $220^{\circ}C,\;420^{\circ}C,\;650^{\circ}C,\;and\;800^{\circ}C$), respectively. The pyrolysis products from tobacco with and without the addition of PG($2\%$) and glycerine($2\%$ were assayed for its pyrolytic behavior. The results showed that a dramatic change in weight of PG and glycerine was observed at $175^{\circ}C\;and\;249^{\circ}C$, respectively. PG and glycerine showed different patterns for their pyrolysis products according to the method of pyrolysis. Namely, the change rate in pyrolysis with DSP was much higher than that of CPP at above $650^{\circ}C$. The major pyrolysis products of PG were propene, acetaldehyde, propanal, and acetol; the major pyrolysis products of glycerine were 2-propenal, 2-propenol, acetol, and acetic acid. In the pyrolysis experiments of tobacco added PG and glycerine, the pyrolysis products of PG and glycerine weren't detected additionally, except for diethyleneglycol diacetate. From these results, it can be concluded that the PG and glycerine added to tobacco would not be expected to pyrolyse extensively during smoking.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.160-169
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• 1995

A mathematical model for the pyrolysis processes during unforced smoldering of cigarette was proposed in this study by analyzing the physical model of the smoldering cigarette (including the establishment of burning front between burning zone and pyrolysis zone, and analyzing the involvement of main factors such as pyrolysis of virgin tobacco, evaporation of water, and internal heat transport in the processes). Thermal conduction of cigarette paper and convective and radiative heat transfer at the outer surface were also considered via the thermal resistance law for the competitive heat transfer mechanisms. The governing partial differential equations were solved using an integral method. Model predictions of smoldering speed, or linear burn rate, as well as temperature and density profiles in the pyrolysis zone for different kinds of cigarettes were found to be close to the experimental data in the literature (Muramatsu, 1981). The model provides a relatively fast and efficient way to simulate the pyrolysis processes and offers a practical tool for exploring important parameters for a smoldering cigarette, such as blended tobacco composition, properties of cigarette paper, and heat flux from the burning zone to the pyrolysis zone.