Descending of a TG analysis curve is proportional to the quantity of products
released during the thermal degradation of the sample. The weight loss is directly
related to the mass loss during the pyrolysis of the organic matter. DTG analysis is
somewhat more accurate. In this analysis, the height of peaks indicates the weight
loss. However, DTG curve shows more maxima allowing a more specific interpretation. The total broad signal corresponds to the yield of the pyrolysis of organic
matter. However, a fine evaluation allows to discriminate hydrocarbons from
functionalized components characterizing the overall chemical composition of the
organic material (see Fig. 4.55). Smaller peak corresponds to the degradation of
other components in the sedimentary rock. For example, during analyses of an oil
shale it probably refers to the degradation of carbonates.
4.4.3 Chemical Degradation
Break down of macromolecular structures for further analysis can be also achieved
by chemical methods. The general approach is similar to pyrolysis, the degradation
products can be used for structure characterization but only very sporadically for
quantification purposes.
RuO 4
OxidaƟon:
R
O
OH
Ether cleavage:
Hydrolysis:
OH -
+
+
BBr 3
R
R
R
O
R
R
Br
O
H
R
R
OH
O
O
H
R
R
O
R
O
Fig. 4.56 Principal reactions of chemical degradation procedures
94
4 Instrumental Analysis
released during the thermal degradation of the sample. The weight loss is directly
related to the mass loss during the pyrolysis of the organic matter. DTG analysis is
somewhat more accurate. In this analysis, the height of peaks indicates the weight
loss. However, DTG curve shows more maxima allowing a more specific interpretation. The total broad signal corresponds to the yield of the pyrolysis of organic
matter. However, a fine evaluation allows to discriminate hydrocarbons from
functionalized components characterizing the overall chemical composition of the
organic material (see Fig. 4.55). Smaller peak corresponds to the degradation of
other components in the sedimentary rock. For example, during analyses of an oil
shale it probably refers to the degradation of carbonates.
4.4.3 Chemical Degradation
Break down of macromolecular structures for further analysis can be also achieved
by chemical methods. The general approach is similar to pyrolysis, the degradation
products can be used for structure characterization but only very sporadically for
quantification purposes.
RuO 4
OxidaƟon:
R
O
OH
Ether cleavage:
Hydrolysis:
OH -
+
+
BBr 3
R
R
R
O
R
R
Br
O
H
R
R
OH
O
O
H
R
R
O
R
O
Fig. 4.56 Principal reactions of chemical degradation procedures
94
4 Instrumental Analysis