Curie-point pyrolysis gas chromatography

M. Carbini, R. Stevanato, M. Rovea, P. Traldi and D. Favretto, Curie point pyrolysis gas chromatography/mass spectrometry in the art field. 2. The characterization of proteinaceous binders, Rapid Commun. Mass Spectrom., 10, 1240 1242 (1996). 

Schulten H-F, Schnitzer M. Structural studies on soil humic acids by Curie-point pyrolysis-gas chromatography/mass spectroscopy. Soil Sci. 1992 153 205-224. 

Pyrolysis-field ionization mass spectrometry (Py-FIMS) and Curie-point pyrolysis-gas chromatography/mass spectrometry (CpPy-CC/MS) of soils... 

Sorge, C., Schnitzer, M., and Schulten, H.-R. (1993). In-source pyrolysis-field ionization mass spectrometry and Curie-point pyrolysis-gas chromatography/mass spectrometry of amino acids in humic substances and soils. Biol. Fertil. Soils 16,100-110. 

Schenck P. A. (1986) Curie point pyrolysis mass spectrometry and Curie point pyrolysis gas chromatography mass spectrometry in organic geochemistry. In Workshop on Advances in Biomarkers and Kerogens. Academia Sinica, Inst. Geochem., Guiyang, China, pp. 83-87. 

Curie-point Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS). 

Natural black (human hair, bovine eyes) and synthetic (tyrosine, dopa, and dopamine) melanins were investigated by Curie point pyrolysis-gas chromatography-mass spectrometry (86,96). The pigments were characterized by different ratios of degradation products identified as aromatic hydrocarbons, phenols, catechols, pyrroles, and indoles. The amount of ash in karakul lamb wool was correlated to its color, with black producing the most (3.9%) and white the least (1.2%). Similar studies showed a correlation with the calcium content (317,318). 

Figure 8.45 Apparatus for pyrolysis gas chromatography. A, filament or ribbon-type pyrolyzer and B, Curie-point pyrolyzer. (Reproduced with perm.i ion from ref. 848. Copyright American Chemical society).

The Curie Point flash evaporation-pyrolysis gas chromatography-mass spectrometric method [32] described in section 2.2.1.2 for the analysis of aromatic hydrocarbons in soils has also been applied to the determination of heteroaromatic compounds (Table 2.2) such as methyledene, isomeric methylidenes, biphenyl and methylbenzofurans. 

A Curie Point flash evaporation-pyrolysis gas chromatography-mass spectro-metric method [35] has been applied to the determination of polystyrenes in soil via identification and determination of their unzipping pyrolysis products, such as styrene monomer, a-methylstyrene, 3-methylstyrene, 4-methylstyrene, a-3-dimethylstyrene, 3-ethylstyrene, a-4-dimethylstyrene, 3,5-dimethylstyrene, a-2- or 2,5- or 2,4-dimethylstyrene, as well as various phenyl ethers. 

R. Hardt and W. Baltes, The analysis of caramel colours. Part 1. Differentiation of the classes of caramel colours by Curie-point pyrolysis-capillary gas chromatography-mass spectrometry, Z Lebensm. Unters. Forsch., 1987, 185, 275-280. 

Curie-point pyrolysis, see also pyrolysis -gas chromatography - mass spectrometry 179-181... 

Pouwels, A.D. Eijkel, G.B. Boon, J.J. Curie-point pyrolysis-capillary gas chromatography-high resolution mass spectrometry of microcrystalline cellulose. J. Anal. Appl. Pyrolysis 1989, 14, 237-280. 

Degradative methods based on pyrolysis are the subject of renewed interest due to the identification power offered by gas chromatography-mass spectrometric systems (GC-MS) (Wershaw and Bohner, 1969 Martin et al., 1977 Meuzelaar et al., 1977 Bracewell and Robertson, 1976). There are two main pyrolysis techniques (1) controlling the decomposition kinetics by temperature programming and (2) the use of quasi-instantaneous heating (e.g.. Curie point pyrolysis). The later technique avoids most recombination reactions, but does not allow kinetic control. The pyrolysis effluent can be detected directly (Rock-Eval method) or after chromatographic fractionation. 

Pyrolysis-gas chromatography was performed using a Horizon Curie-Point Pyrolator with a pyrolsis temperature of 710°C held for 10 s. The interface was heated to 300°C and the capillary column was directly inserted into the pyrolysis chamber. Parameters for the gas chromatographic separation are described below. For Py-GC/MS analyses the same Pyrolysator device was linked to a GC/MS-system with chromatographic and mass spectrometric conditions as described below. 

Buco, S., Moragues, M., Doumenq, P., Noor, A., and Mille, G., Analysis of polycyclic aromatic hydrocarbons in contaminated soil by Curie point pyrolysis coupled to gas chromatography-mass spectrometry, an alternative to conventional methods, J. Chromatogr. A, 1026, 223-229, 2004. 

Scheijen, M.A., J.J. Boon, W. Hass, and V. Heemaim Characterization of tobacco hgnin preparations by Curie-point pyrolysis-mass spectrometry and Curie-point pyrolysis-high resolution gas chromatography/ mass spectrometry J. Anal. Appl. Pyrolysis 15 (1989) 97-120. 

Pyrolysis-gas chromatography (Py-GC) Thermal decomposition is one of the oldest methods for studying the composition of polymers, and is a valuable tool in the industrial analysis of plastics. The analytical use of Py-GC is based on the fact that the polymer structure determines its reactivity and thus also the qualitative and quantitative composition of the pyrolysis products. The technique combines the advantages of a highly efficient separation method with a directly connected pyrolysis unit, so that the degradation products can be analyzed immediately after their formation. Curie-point pyrolyzers yield the most reproducible results due to short temperature... 

Pyrolysis gas chromatography (PGC) was one of the first combination gas chromatographic techniques, yet it is still plagued by problems of accuracy and repeatability of pyrolysis conditions and laboratory-to-laboratory reproducibility. There are three major devices for PGC (1) heated wire or ribbon, (2) tube furnace, and (3) Curie point filament. The heated wire or ribbon apparatus uses resistive heating to provide flash pyrolysis from ambient temperature to 1400°C. It can be controlled to reach the maximum temperature in milhseconds or at some fixed rate, and the device can hold the top temperature for a settable fixed time. These high-precision devices can be placed directly in the injection port (for vertical injection ports). The temperature reading should be checked from time to time to ensure accuracy. 

Jackson and Walker studied the applicability of pyrolysis combined with capillary column gas chromatography mass spectrometry to the examination of phenyl polymers (eg. styrene-isoprene copolymer) and polymer like phenyl ethers (eg. bis(m-(m-phenoxy phenoxy)phenyl)ether). They examined the effect of varying parameters affecting the nature of products formed and relative product distribution in routine pyrolysis. These parameters include the effects of pyrolysis temperature rise times, pyrolysis temperatures up to 985 C and pyrolysis duration. Temperature rise time (0.1 to 1.5 s) is not a critical factor in the Curie point pyrolysis of a styrene-isoprene copolymer, either with regard to the nature of the products formed or their relative distributions. Additionally, the variation of pyrolysis duration or hold time (2.0 to 12.5 s) at a fixed Curie temperature reflected no change in the nature of components formed however changes in product distributions were observed. Variations in Curie temperature at a fixed pyrolysis duration produced drastic changes in product distributions such as a three-... 

Roussis, S.G. and Fedora, J.W. (1998) Use of a thermal extraction unit for furnace-type pyrolysis Suitability for the analysis of polymers by pyrolysis/GC-MS. Rapid Commun. Mass Spectrom., 10, 82-90. Schulten, H.-R., Fischer, W., Wallstab, H.-J. (1987) New automatic sampler for Curie-Point pyrolysis its combination with gas chromatography. HRC CC, 10, 467. 

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