Pyrolysis starch

Because of its practical importance, significant effort was made to understand the pyrolysis of starch rather than one of its components. Data are also available on amylose pyrolysis alone, but much less on amylopectin. However, the pyrolysis products of these compounds are expected to be the same. Starch pyrolysis generates... 

Some less volatile compounds formed in starch pyrolysis at 590° C were seen, as expected, only in the trimethylsilylated pyrolysate. Figure 7.4.2 shows the chromatogram of a starch pyrolysate performed at 590° C off-line, followed by trimethylsilylation (with BSTFA) and separated on a DB5 column (60 m long, 0.32 mm i.d. and 0.25 n film thickness). 

As seen in Table 7.12.1, the same compounds were identified in starch pyrolysis (see Tables 7.4.1, 7.4.2, and 7.4.3). Glycogen pyrolysis was utilized in a series of studies to identify this compound in biological samples and in mixtures with other biopolymers (see Part 3). Studies were also done to determine the influence of the matrix on the Py-MS results for glycogen [68a]. 

Early work had indicated that the course of starch pyrolysis is also altered when such simple salts as sodium chloride and sodium carbonate are present. In an attempt to investigate this phenomenon in more detail, Bryce and Greenwood studied the kinetics of the decomposition of amylomaize starch (high-amylose, maize starch) in the presence of two series of salts one having a common cation (NaH2P04, Na2B407, NaCl,... 

The data from Kroller (2195) on the B[a]P yields generated dnring cellnlose and starch pyrolysis may be compared with those of Gilbert and Lindsey (1289), see Table XXV-28,. This provides an excellent example of the effect of changing pyrolysis conditions (pyrolysis at 650°C in air vs. pyrolysis at 700°C in N2) when two different materials are considered. The different pyrolysis conditions give a ratio of 9.75 (0.78/0.080) for the B[a]P yields from cellnlose, bnt a ratio of 2.43 (0.17/0.070) for the B[a]P yields from starch. 

Although the pyrolysis of some classes of polysaccharide materials has been studied quite extensively in the food, petrol and tobacco industry, very little has been published specifically on polysaccharide binders (arabic gum, tragacanth gum, fruit tree gum, honey and starch). The pyrolysis of glucane based polymers, especially cellulose, has been studied in detail [6,55], highlighting how anhydrosugars and furan derivatives are the main pyrolysis products, together with one-, two- and three-carbon aldehydes and acids. 

Implementation The GC-MS of the sample headspace finds no perfume compounds. The cream is found to be greater than 80-wt% organic matter. Pyrolysis-GC-MS identified significant levels of glucose polymers, which were confirmed by FTIR to be either cellulose or starch. The iodine test revealed that the glucose polymer was starch. Further GC-MS analysis did not find cholesterol, but did find trace levels of a cholesterol degradation product. 

These carbonaceous catalysts can be obtained by the sulfonation of incompletely carbonized organic compounds [42]. Note that starch and cellulose can be used as carbon precursor [43, 44]. After the incomplete pyrolysis of the carbon precursor, the SO3H groups have been introduced by sulfonation with sulfuric acid (Scheme 3). After this treatment, the presence of phenolic hydroxyl, carboxylic acid, and sulfonic groups at the surface of these amorphous carbonaceous materials has been demonstrated. 

A series of 10 polycyclic compounds and blends with starch, Bakelite, and hydrogenated creosote were employed as model substances to examine the effect of carbon, hydrogen, and oxygen on sulfur distribution during pyrolysis at a temperature of about 625°C. 

Starch and Bakelite were obtained from stock supplies and were used as-received for pyrolysis studies of blends. Hydrogenated creosote was prepared in the laboratory by catalytically hydrotreating a 270°-355°C. creosote fraction to remove all heterocyclic impurities and to saturate completely the ring systems. 

Bryce, D. J., and Greenwood, C. T. (1966). The thermal degradation of starch. Part 6. The pyrolysis of amylomaize starch in the presence of inorganic salts. In Thermoanalysis of Fibers and Fiber-Forming Polymers, Applied Polymer Symposium, Vol. 2, pp. 159-173. Interscience, New York. 

Keywords carbon-silica adsorbents, fumed silica, pyrolysis, glucose, starch, cellulose, phosphoric acid, polyvinylpyrrolidone, polystyrene, structural characteristics. 

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