Curie point pyrolysis 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. 

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... 

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. 

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. 

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

In a later paper, De Haan et al. (1981b) report on the seasonal variation in the composition of fulvic acids determined by Curie point pyrolysis-mass spectrometry. Water samples were collected monthly between January and September, 1978, and fulvic acid fractions were isolated by gel permeation chromatography. Differences in the chemical composition (particularly striking in the pyrograms of fractions of high apparent molecular weight)... 

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. 

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). 

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. 

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. 

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. 

Analytical pyrolysis is defined as the characterization of a material or a chemical process by the instrumental analysis of its pyrolysis products (Ericsson and Lattimer, 1989). The most important analytical pyrolysis methods widely applied to environmental samples are Curie-point (flash) pyrolysis combined with electron impact (El) ionization gas chromatography/mass spectrometry (Cp Py-GC/MS) and pyrolysis-field ionization mass spectrometry (Py-FIMS). In contrast to the fragmenting El ionization, soft ionization methods, such as field ionization (FI) and field desorption (FD) each in combination with MS, result in the formation of molecule ions either without, or with only very low, fragmentation (Lehmann and Schulten, 1976 Schulten, 1987 Schulten and Leinweber, 1996 Schulten et al., 1998). The molecule ions are potentially similar to the original sample, which makes these methods particularly suitable to the investigation of complex environmental samples of unknown composition. 

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. 

It should be noted that all of the above-described pyrolytic devices suffer from a serious drawback. Although relatively good reproducibility of the results can be attained on the same device, devices of the same model from the same manufacturer often show poor reproducibility. Until about 1970 it was considered that the best reproducibility as regards the composition of the pyrolysis products could be achieved on a Curie-point pyrolyser [77]. However, a comparative study of the results obtained in 18 laboratories on the same sample, conducted by the Py—GC subgroup of the Chromatography Discussion Group of the Institute of Petroleum in London, has shown that Curie-point cells are characterized by the same scatter of data as cells of the other types [78]. 

Gas-Liquid Chromatography - Acetylated glycosyl fluorides have been identified by this procedure, and capillary gas chromatography has been employed in pyrolysis studies of disaccharides using a Curie-point pyrolyser. ... 

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