Papers by Keyword: Py-GC/MS

Abstract: There is a growing interest in new technologies for power generation, making use of renewable natural resources. Fast pyrolysis is an effective and promising process of thermal decomposition of organic materials. This study evaluated the thermal decomposition of three different types of lignin and investigated the composition of the volatiles formed during the analytical pyrolysis. The thermogravimetric analysis, which is a widely used analytical technique to observe the thermal behavior of materials, was used to investigate the decomposition of the samples at different heating rates. The micropyrolysis is a fast and reliable analytical technique that provides useful background information for development of the complex process production of bio-oil. This study evaluated the composition of the vapor formed during analytical pyrolysis at 450, 550 and 650°C. The curves obtained by thermogravimetric analysis indicate the degradation of all lignin samples takes place in a wide temperature range. Analytical pyrolysis tests for three types of lignin showed formation of phenolic compounds as most significant components.

Abstract: Activated carbon (AC) was reported as a promising catalyst to selectively produce phenolic compounds from biomass using the micro-wave assisted catalytic pyrolysis technique. In order to evaluate the catalytic performance of the AC under the traditional fast pyrolysis process, analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique was applied for the catalytic fast pyrolysis of biomass mixed with the AC. Polar wood was selected as the feedstock, and experiments were conducted to reveal the AC-catalyzed poplar wood pyrolysis behavior and product distribution. The results indicated that the AC was also effective for the phenolics production in the traditional fast pyrolysis process at 350 °C. It could promote the formation of phenolic compounds, and inhibit most of the other pyrolytic products. The maximal phenolics yield was obtained at the biomass to catalyst ratio of 1:4, with the peak area% over 50%.

Abstract: High temperature pyrolysis of sawdust was achieved by using the analytical Py-GC/MS technique which allowed the on-line analysis of the pyrolysis product.The experiments at the different temperatures (700-1000°C) and the different mass ratios of CaO to sawdust (0%,10%,30%,50%) were carried out,respectively. At different temperatures, the distribution of condensable products considerably changed. At 700°C,the aromatic hydrocarbon yield were 0.9% of the total peak area. However, the aromatic hydrocarbon yield reached 59.4% of the total peak area at 1000°C, which might be due to the occurrence of the condensation polymerization at high temperature. CaO had a positive effect on decreasing the yield of the condensable products of sawdust pyrolysis, but did not remarkably change the distribution of the condensable products.

Abstract: Analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed for the fast pyrolysis of glucose, cellubiose and cellulose in this study. The pyrolytic products from the three glucose-based materials were determined and compared to reveal the distribution differences. The results indicated that fast pyrolysis of the three materials obtained similar pyrolytic products, including the anhydrosugars, furans, linear carbonyls and cyclopentanones, but the distribution of the pyrolytic products differed from each other. The cellulose formed more anhydrosugars, but less carbonyls and furans than the glucose and cellubiose. The glycosidic bond of the cellubiose and cellulose would favor the pyrolytic depolymerization reactions to form various anhydrosugars, while inhibit the pyrolytic fragmentation reactions to produce linear carbonyls.

Abstract: Pyrolyzation of lignin to aromatic compounds with small molecule weight is one of the ways to efficient utilization of lignin resource. Basing on the data of thermogravimetric scanning curve (TG-DTG) and pyrolysis-gas chromatography -mass spectrometry (Py-GC-MS), the change in the distribution of pyrolysis products at different temperature was analyzed. The results showed that lignin could produce a large number of aromatic compounds having hydroxy or methoxy groups under the conditions of anaerobic and 250-450°C, but it was not benefit to obtain useful organic compounds when pyrolyzed at elevated temperatures.

Abstract: In order to evaluate the safety of Eucalyptus wood interior, Eucalyptus urophydis wood was used and extracted in benzene-alcohol solution, and its extractives were identified by Py-GC/MS. The main and abundant constituents of 350°С pyrolysis products were 1-phenanthrenecarboxylic acid, 1,2,3,4,4a,9,10,10a-octahydro-1,4a-dimethyl-7-(1-methylethyl)-(5.38%), stigmasterol,22,23- dihydro- (4.67%), 3'-chlorooxanilic acid n'-(3-ethox y-4-hydroxybenzylidene)hydrazide (4.13%), stigmast-5-en-3-ol, oleate(3.83%), 2-ethylacridine(3.32%), etc. The main and abundant constituents of 600°Сpyrolysis products were decanoic acid, 1,2,3-propanetriyl ester(33.8%), dodecanoic acid, 1,2,3-propanetriyl ester(8.03%), decanoic acid, 1,2,3-propanetriyl ester(3.99%), 1-chloromethyl-1-(2-propenyloxy)-1-silacyclohexane(3.98%), etc. So there was much biological medicine and health care composition in Eucalyptus urophydis wood. And the wood was safety.

Abstract: In order to learn of pyrolytic behavior of wheat straw multifunctional materials, the extractives of wheat straw biomass were adsorbed and determined by Py-GC-MS. And the main constituents were stigmasterol, vitamin e, campesterol, .gamma.-sitosterol, stigmasterol, 22,23- dihydro-, nonacosane, stigmastan-3,5,22-trien, heneicosane, lup-20(29)-en-3-one, 1,2- benzenedicarboxylic acid, buty l 2-methylpropyl ester, stigmast-4-en-3-one, stigmastan-3,5-diene, 4,22-stigmastadiene-3-one, cholest-5-en-3-ol (3.beta.)- , pyridine-3-carboxamide, oxime, etc.

Abstract: In order to find out its active behavior, the extractives of wheat straw biomass were adsorbed and determined by Py-GC-MS. And the main constituents were eicosane, stigmasterol, 22,23-dihydro-, .gamma.-sitosterol, stigmasterol, campesterol, nonacosane, stigmast-4-en-3-one, lup-20(29)-en-3-one, 13-tetradecen-1-ol acetate, 1,3-butadiene, 2- methyl-, 9-octadecenoic acid, (e)-, acetic acid, stigmast-5-en-3-ol, oleate, 1-nonadecene, heptacosane, 4,22-stigmastadiene-3-one, 4-((1e)-3-hydroxy-1-propenyl)-2- methoxyphenol, 1-heptene, 2-isohexyl-6-methyl-, etc.

Abstract: In order to find out its active materials, the extractives of wheat straw biomass were adsorbed and determined by Py-GC-MS. And the main constituents were 1-phenanthrenecarboxylic acid, 1,2,3,4,4a,9,10,10a-octahydro-1,4a-dimethyl-7-(1-methylethyl)- (31.32%), 1,3-pentadiene,(z)- ( 4.5%), cyclobutene(2.17%), 1-nonadecene(2.12%), etc.

Abstract: An analytical pyrolyzer coupled with Gas Chromatography and Mass Spectrometry (Py-GC/MS) was employed to study the influence of HZSM-5 on the pyrolysis products of cellulose. The results revealed that pyrolysis products of cellulose consisted of light molecular weight products with linear chain, anhydrosugars and furan compounds. Light molecular products were mainly acetaldehyde and 2-propanone, 1-hydroxy; anhydrosugars were mainly levoglucosan (LG), levoglucosenone (LGO) and 1,4:3,6-Dianhydro-α-d-glucopyranose (DGP); Furans were mainly furfural (FF) and 5-(hydroxymethyl) furfural (HMF). The addition of HZSM-5 changed the contents of main products from fast pyrolysis of cellulose, especially for aromatic hydrocarbons, which belonged to light molecular products and increased rapidly. In addition, plenty of carbon dioxide appeared. With the addition of HZSM-5, the dehydration of LG was enhanced to produce LGO and then LGO was further decomposed into small molecular products with HZSM-5: cellulose ratio increasing. And the formation of FF and HMF were both inhibited with the addition of HZSM-5, but the formation of furan was improved. It was inferred that the addition of HZSM-5 could effectively promote the further dehydration of initial products from cellulose fast pyrolysis by the breakage of side chain.