SYNTHESIS AND CHARACTERIZATION OF ALLOPHA NIC SOILS

Iron oxide coated aluminosilicates, with similar percentage of Fe repo rted for Chilean Andisols, are obtained by the wet impregnation method . Mossbauer spectroscopy showed that deposited iron oxide corresponds to ferrihydrite. The proposed methodology does not affect aluminosilic ate stability and colloid particle morphology, but reduces the access to micropores. When organic matter is deposited on iron oxide coated a luminosilicates, synthetic compounds similar to Andisols, in compositi on and characteristics, are obtained. It is concluded that the propose d synthesis is a suitable alternative to carry out surface studies rel ated with Chilean soils derived from volcanic materials.