8 
BSH Report No. 56 
Fig. 4a (top), 4b (bottom): GC-FID Chromatograms of differently appearing paraffin wax samples 
(maximum-.normalized and expressed as relative percentage). Note that it is the CENT/Tr’s GC-FID 
method here. This method is not sufficient to deal with paraffin waxes containing the higher boiling 
n-aikanes as sample DE10_1067 (bottom) clearly shows. 
In order to parametrise the bell-shape curve and the above-mentioned proper 
ties, peak detection and extraction of Intensities (pIco-Ampere, [pA]) were 
applied to each n-alkane present In a GC-FID-chromatogram. Consequently, 
each sample Is represented as a data set, consisting of Individual peak Intensi 
ties of all the n-alkanes present In the corresponding chromatogram. 
Similar as It Is In case of oil, It can be assumed that there Is always a homo- 
logue series of n-alkanes. This means once the starting n-alkane Is success 
fully Identified the following Identification Is easier since there Is a predictable 
pattern to follow and absolute retention times are not as critical as In other ana 
lytical approaches.