Properties of zeolitized tuff/organic matter aggregates relevant for their use in pedotechnique. I: chemical and physical-chemical properties

A study aiming at evaluating the technical and economic suitability of zeolitized tuffs as mineral substrate for soil re.building in pedotechnique strategies was carried out. The chemical and physical-technical properties of aggregate ped models, obtained by interaction between tannic acid, i.e. an organic matrix precursor of humic substances, and zeolotized material, namely Neapolitan Yellow Tuff usung Ca ions as "bridge", were investigated. Ped models were characterized according to chemical and physical standard methods for soil analysis, color analysis by visual interpretation and by spectroradiometry, as well as by FT-IR spectroscopy. The results suggest that the interaction between zeolite, Ca ions and tannic acid leads to the formation of stable aggregates with peculiar chemical and chemical-physical properties.