DETERMINATION OF VOLATILE FATTY-ACIDS IN LANDFILL LEACHATES BY GAS-CHROMATOGRAPHY WITH DISTILLATION PRETREATMENT

Gas chromatography with flame ionization detection (GC-FID) was used to determine the volatile fatty acids in landfill leachates. Distillation was investigated for sample pretreatment. A sample was distilled with sulphuric acid to increase the recovery of fatty acids and remove the longer resident species and inorganic salts. The light-end distillate was discarded prior to the chromatographic step. Concentration ratios of volatile fatty acids in the distillate to sample solution were studied. Ghost peaks on the gas chromatogram were eliminated by high-temperature conditioning. The results indicated that the method is applicable to fatty acid determinations, with very good correlation coefficients for the calibration graphs. The application of the distillation-GC-FID method is illustrated for leachate samples from the Taichung sanitary landfill.