5. Real samples analysis
The proposed separation system was applied to determine
SCFAs in samples of leachate from a municipal landfill. An exemplary
chromatogram is given in Fig. 4, and the level of the
SCFAs in the landfill leachate ranged from 0.45 to 15 mg L−1.
The contents of particular acids are presented as average of
4 measurements ± extended uncertainty for significance level
˛= 0.05 and caluculated as U = k · s/√n.; for n = 4 and ˛= 0.05,
k equals 2. Ethanoic acid was at the highest concentration of
15.2 ± 0.73 mg L−1 and the second highest was propanoic acid
(4.5 ± 0.19 mg L−1). The other analytes were 2-methylpropanoic
acid (1.21 ± 0.061 mg L−1), butanoic acid (2.12 ± 0.074 mg L−1), 3-
methylbutanoic acid (0.48 ± 0.077 mg L−1) and pentanoic acid
(0.45 ± 0.059 mg L−1). Hexanoic, heptanoic and octanoic acids were
below LOQ