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Pyrolysis, analytical method Applications

If biomass is subjected to the ASTM D 3172 procedure for determination of fixed carbon, chemical transformation of a portion of the organic carbon in biomass into carbonaceous material occurs as described here. All of the fixed carbon determined by the ASTM procedure is therefore generated by the analytical method. Furthermore, the amount of fixed carbon generated depends on the heating rate used to reach biomass pyrolysis temperatures and the time the sample is subjected to these temperatures. Nevertheless, such analyses are valuable for the development of thermal conversion processes for biomass feedstocks. But application of the ASTM procedures to biomass might more properly be called a method for determination of pyrolytic carbon or coking yields. In the petroleum industry, the Conradson carbon (ASTM D 189, differ-... [Pg.237]

In an early study, now primarily of historical interest, W. Noble et al. dealt with the characterization of adhesives by pyrolysis gas chromatography and IR spectroscopy. The scope of this study, in which 179 commercial products were analyzed and two complementary analytical methods were employed, provides a useful model, though the applicability of the results is limited by the obsolescence of the instrumentation used. [Pg.122]

Finally, in many cases the pyrolysis product distribution is so complex that it is not possible to separate and identify all of the components. In such cases a chemometric method, simply treating the pyrogram as a pattern, can be used to compare one sample with another. This approach has foimd many applications in forensic analysis, for example, of paints and in analysis of authenticity of art works (54). It has even been used to type bacteria (55-57). These applications often take advantage of the fact that the high sensitivity of the analytical method allows minute samples to be analyzed they depend upon a database of pyrograms obtained under well-controlled conditions and analysis involves a statistical pattern-matching approach. [Pg.2113]

Recently, many useful applications of analytical pyrolysis for the analysis of diverse lignin samples have been reported. The method has proven to be extremely useful for a quick comparison of lignins of different origins. Based on the peak areas of H-, G-, and S-derived pyrolysis products in the pyrogram, lignins can be easily classified as G- or G/S-type. The results of such a comparison are shown in Fig. 4.7.11. Pyrograms of MWLs from spruce, teak, beech and whitewood show clearly the increase in S-derived pyrolysis products. [Pg.190]

Detection of biomass is an important application of analytical pyrolysis and it includes several topics. One such topic is the measurement of microbial biomass in attempts to substitute for traditional microbiological methods. Another topic is the detection of specific biomarkers for geochemical logging purposes. Pyrolytic studies were also useful in organic marine geochemistry [72]. An interesting application of biomass detection is the search for life in extraterrestrial samples. [Pg.477]

Barter, S.R. and Horsfield, B., 1993. Determination of structural components of kerogens by the use of analytical pyrolysis methods. In Engel, M.H. and Macko, S.A. (eds). Organic geochemistry. Principles and applications. Plenum Press, NY, pp. 271-287. [Pg.165]

Elevated temperature reaction pyrolysis in which the analyte is reacted with a chemical reagent. The method is appropriate for those materials that contain hydrolyzable bonding or free reactive groups, e.g., acids, alcohols, and phenols. Usually, the pyrograms more clearly reflect the composition of the parent material. A review of the technique describes applications to nonforensic materials. ... [Pg.198]

Improvements in analytical capability for the analysis of complex pyrolysate mixtures have appeared during the last decade high-resolution capillary GC with more polar and selective stationary phases coated on inert fused-silica colmnns coupling of capillary GC with sensitive, selective, and lower-cost mass spectrometric detectors enhanced pyrolysis-MS techniques hyphenated analysis methods, including GC-Fourier-transform infrared spectroscopy (GC/FTIR) and tandem MS and better strategies for handling complex multidimensional pyrolysis data. The present chapter reviews the known chemotaxonomy of miCTOorganisms, summarizes practical considerations for the use of pyrolysis in microbial characterization, and critically discusses selected applications of analytical pyrolysis to microbial characterization. [Pg.203]

PyMS is capable of generating useful data on intact foodstuffs or associated microorganisms (food poisoning bacteria, for example). PyMS is based on the controlled thermal degradation of samples under inert conditions to produce mixtures of volatile compounds that are swept into the mass spectrometer ion source and ionized by El or Cl. The resulting fingerprint spectrum of the analyte contains characteristic features that can be classified by chemometric methods. Pyrolysis is sometimes combined with GC-MS in order to extract more information from the analyte. Applications of PyMS in the food sciences include quality assurance and authentication of food and drinks, analysis of cell wall material in food plants, and identification of food microorganisms. [Pg.2929]

Recently, carbon NPs with ECL activity have been prepared by an electrochemical method [101] as well as through a facile and economical microwave pyrolysis approach [108]. On heating, a saccharide and surfactant PEG-200 mixture solution in a 500 W microwave oven for 2-10 min, the colorless solution was transformed to yellow and finally to dark brown, which entails the formation of carbon NPs. This case represents a convenient and low-cost method which decreases the reaction time and devotes a potential advancement to large-scale industrialization. It s highly sensitive analytical applications emerged by the advantages of convenience, low cost, and effectiveness of the method. [Pg.53]


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