IDENTIFICATION OF PEAT AND LEONARDITE USING HUMIFICATION PARAMETERS AND ISOELECTRIC-FOCUSING (IEF) - A FIRST APPROACH

Several samples of peat and leonardite (organic fossil material of veg etable origin) and of humic extracts from peat and leonardite were cha racterized using some humification parameters and isoelectric focusing (IEF). The HA/TOC and the humification rate (HR) show values lower th an 60% for peat and higher than 70% for leonardite samples. These two parameters are useful to distinguish peat from leonardite, but unable to: identify the organic materials in the humic extracts. Feat an leon ardite samples and their humic extracts were characterized using IEF a nd evaluating the quantitative distribution of the bands of the profil e. The group of bands in the range from pH 4.8 to 5.5 (region C) is ch aracteristics in all samples. In particular, the relative area is less than 55% for peat and humic extracts from peat and higher than 60% fo r leonardite and humic extracts from leonadite.