Aliphatics in Soil Organic Matter in Fine-Clay Fractions
1990
Schulten, H. -R. | Schnitzer, M.
Fine-clay fractions were separated from three agricultural soils and extracted sequentially with n-hexane, chloroform and supercritical n-pentane. The resulting extracts were analyzed by field ionization (FI) and field desorption (FD) mass spectrometry (MS). The major components indentified included C₁₁ to C₉₄ n-alkanes, C₁₃ to C₃₄ n-fatty acids, n-C₁₆ and n-C₂₄ diols, and C₃₈ to C₆₇ n-alkyl monoesters. Minor components were C₂₂, C₃₂, and C₃₄ n-alcohols, C₂₇ and C₂₉ sterols, C₅₆ to C₉₁ n-alkyl diesters, C₈₃ to C₉₉ n-alkyl triesters, and C₁₇ to C₂₁ unsaturated monocarboxylic acids in extracts of one clay only. The highest molecular weight compound identified was the C₉₉ n-alkyl triester (m/z 1478). Especially noteworthy was that: (i) similar aliphatics were extracted from the three clays, (ii) the compounds identified were typical of components of natural waxes, which appear to be present in the organic matter in fine-clay fractions, and (iii) the soft ionization mass spectrometric methods employed were found to be eminently suitable for the identification of medium to high molecular weight aliphatics in the organic matter in fine-clay fractions.
显示更多 [+] 显示较少 [-]